JBL 2440 vs TAD4001

[sa660]

What should I go for?

I am in a position to choose between a pair of JBL 2440 and a pair of TAD4001 for an exchange with a single westrex electric compression drivers

I have JBL tweeters 2 off each 2402/2403/2404/2405.

I beleive TAD are very good and JBL very valuable. The 2440 are still pack in carton and new with a single spare diaphragm. The TAD are use for home use only.

Both very good I guess.

Let me know what you would pick please?

Thanks

[Mr. Widget]

As long as the TADs are not ugly rust buckets they win both in terms of sonic value and resale value.

A pair of decent looking TAD 4001s are very hard to get for less than $1200-$1500.

A couple of years ago there was someone on eBay selling NOS (real new old stock in sealed boxes) 2441s and he was getting $1000 per pair for them.

Now if they were factory sealed NOS 375s it would be a different story. The TADs would still sound better, but some collector would pay $2000 or more for the 375s.

Having personally recently compared freshly diaphragmed 2441s to a pair of TAD 4001s, I can't recommend the 4001s highly enough.

Widget

[whgeiger]

TAD TD4001 wins when mounted on an appropriate horn.

For a matching horn and performance data, see my recent post in the Technical section.

Regards,

WHG

[Maron Horonzakz]

Sonicly the TAD 4001,s win. Flat to 20k and 5 slit phazing plug with Be diaphrams give them excellent clarity.

[4313B]

Does TAD make a 1.5" throat version that will bolt to the H9800 horn?

[whgeiger]

G,

Both the TAD 4002 (sans adapter) and the TD-4003 have 39mm dia. throat exits.

For horn mounting, the TD-4002 uses (4) M7 cap screws on 87.5 mm BCD and the TD-4003 uses (4) M6 cap screws on 87.4 mm BCD.

For best results, slope at the horn entry should match that at the driver exit. Use a 2” entry horn with an adapter to match both slope and diameter of both openings. In the case of sectoral horn this adapter also serves as a round to rectangular transition.

Using this tack both the TD-2001 and TD-2002 (25.4mm throat dia.) become candidates for use with a 1.5” dia. entry horn.

Regards,

WHG

[sa660]

It looks like if for the sound nirvana quest TAD would be better.
But I am a fan of JBL and own several JBL drivers like 2441, 2450 and was hoping that the JBL 2440 had some good performance for the midrange rather than a flat response up to 20khz.

Another person suggested to use the JBL for mid and a high frequency tweeter rather than using the single TAD 4001?

for example JBL 2440+2403 would be better than the TAD4001 with the proper horns


whgeiger can you please point me in the right direction for the latest post in tecnical please.

thanks for your opinions

[Mr. Widget]

Originally posted by Giskard
Does TAD make a 1.5" throat version that will bolt to the H9800 horn?

Funny you should ask. I've ordered a pair of 4003s. I hope to have them sometime next week. As WHG points out it is a 1.5" exit driver. Like the 435Be it uses Neodymium to keep weight down. Unlike the 435Be it uses a 4" diaphragm. The 4001 and 4002 both share a 4" diaphragm, but the 4003 is a complete redesign were they used a new method of VC attachment to keep moving mass down to a minimum. This, combined with a slightly different phase plug increases the UHF output of the 4003 over the 4001 or 4002.

Back to your question, I do intend to try them together. I doubt the bolt pattern will be the same, but I will rig it.

WHG,

The slope issue will be different here as the throat of the H9800 is perfectly round at 1.5". It smoothly blends from a circular to rectangular section. Here is a side section from the Project May.

Widget

[Mr. Widget]

SA660,

Take a look at this excerpt from JBL Technical Note Volume 1, number 8, page 3.

This compares the 2440, 2441, and the TAD 4001 all on a JBL 2350 horn. It is clear the TAD has the flattest mid-range as well as being the most extended. In addition the graph does not show how the Beryllium diaphragm allows the 4001 to render better micro detail.

I love JBL too, but in the quest of ultimate quality... besides the 4001 is a 2440 descendant in design and was designed by a former JBL designer, Bart Locanthi.

Widget

[sa660]

This show that with the proper correction in the crossover you should be able to flaten the peek of the TAD4001 and get the extend reponse flat.
OR attenuate the 2441 before the roll off to obtain a flater response.

I would love to see other JBL 2" driver like the 2450 and 2445/6 on the same graph.


thanks,

[whgeiger]

Quote:
“whgeiger can you please point me in the right direction for the latest post in tecnical please”

R,

See:
http://www.audioheritage.org/vbulletin/showthread.php?s=&threadid=2955

Regards,

WHG

[scott fitlin]

JBL 24XX are good, very good, but the TAD 4001,s are better! Its the cleanest, and most coloration free compression driver you can buy!

I have heard the 4001 on JBL 2395,s as well as TAD,s maple wood horn! Very clear sounding! Also spooky holographic sound, too.

They are a bit persnickety to setup, and if somethings not quite right with your setup, youll hear it through these drivers!

Im told that the Beryllium diaphragm is responsible for the drivers extremely fast repsonse to signals, and thats why its micro-detail is so good.

The only drawback to TAD is the price. Brand new 4001,s are ridiculously expensive, and so are replacement diaphragms! However, if reliability is your concern, my buddy has six 4002,s on JBL 2395,s in a club called Stereo, and the diaphragms are the same as the 4001,s, powered by a Bryston 3B SST, three horns per channel, and they pound the shit out of this system, and in the almost two years they have been in service, not ONE single blown driver! If it can do it there, it can do it anywhere! The mids are one of the most outstanding aspects of Stereo,s system, though!

Now I guess all this TADTALK means Im gonna have to get my 4002,s out and give them a whirl!

[Oldmics]

Todays Testing Project

[paragon]

Hello,

If you love JBL buy JBL, but the TAD is the better driver.
There was a test in a speaker magazine between the
JBL 2445 an the TAD 4001 in a coaxial 15 inch bass driver
and the TAD goes flat to highest frequencies, while the JBL
"oszillates" over 10 KHz.
I am a JBL Lover, but the TAD is the best you can buy
(for a lot of money) !!

Regards
Eckhard

[Maron Horonzakz]

Beryllium Is black On the TAD diaphrams? I thought they would be light grey. The 5 slit phazing plug is impressive.

[Oldmics]

Sorry for the poor photos.

Oldmics

[Oldmics]

My test mic falls off rapidly after 20K.I will soon remedy that.

[scott fitlin]

Considerable difference between the TAD and the JBL!

[Oldmics]

As you can see,the JBL falls off much earlier

Oldmics

[scott fitlin]

Do you have the frequency graph of the TAD 4002? Im curious to see that as well!

[Oldmics]

I do have the 4003 graph if you would like to see that.

Never tested the 4002.

IMHO only minor differences in the freq response between the 4001 and 4003.That would be in the top end although both begin to roll off @ exactly 10.59K .The 4001 stretchs to a lower usable freq point,3db down @644 hz compared to the 4003 @ 754 hz.

Oldmics-Searching for a flat response to infinity!!!

[Tom Loizeaux]

If you're going to require that the compression driver take you all the way to the top, then the TAD 4001 is a great choice. If, however, you're going to add a 2405, or the like, to finish off the high end, then the JBL compression driver, crossed over at 9K, would also be a great choice.
It is true that the TAD 4001 through the correct wood horn (see Westlake) is an outstanding driver!
Keep us posted.

Tom

[scott fitlin]

Originally posted by Oldmics
I do have the 4003 graph if you would like to see that.

Never tested the 4002.

IMHO only minor differences in the freq response between the 4001 and 4003.That would be in the top end although both begin to roll off @ exactly 10.59K .The 4001 stretchs to a lower usable freq point,3db down @644 hz compared to the 4003 @ 754 hz.

Oldmics-Searching for a flat response to infinity!!! OK, lets have a look at the 4003,s graph.

Oldmics, how do you like the sound of the 4003 compared to the 4001? I know engineers who swear the 4003 is the ONE! Of course, then theres everybody else who say the 4001 is the best compression driver ever made!

I have the 4002,s and I think the 4001 sounds better, although the 02 is no slouch, but I found the neodymium drivers have a different tonality than Alnico ones. One of the things I noticed different about the sound of the 4002 as compared to the 4001 was the upper end of the mids sound crisper through the alnico driver. The 4002 has a more pronounced lower mid, is similar to a degree, to the JBL 2450.

Curious to hear what you think!

[Oldmics]

Hi Scott

Unfortunatly I can not answer your question regarding the differences in how the drivers sound.As silly as this will sound,I did not get a chance to listen to the 4003 drivers.I only had time enough for testing the units.

Now there will soon be a person on the forum who will be able to answer your question.That would be Mr.Widget.

This particular pair of drivers were acquired for a project the Widget is working on.He personally has 4001 drivers and will be testing and listening to these 4003 against the 4001 units.I am sure he will post his findings here,although it will be a few weeks before he is ready to do so.

I can comment about the 4002 V/S the 4001.Although I have not tested the 4002 I have extensive listening time with both drivers.I agree with your conclusion that they sound different.It may be due to different material used in construction of these drivers.

As the chart will show,there are differences between the units.I also am awaiting Mr. Widgets sonic evaluation and his preference on these esoteric noise machines.

Oldmics

[scott fitlin]

Last year I purchsed 6 TAD 4002,s. Many told me to go with the 4001,s, but, TAD told me to use the 4002, and they are good, but, for whatever reason, they didnt do like I thought they would.

Im not saying they are bad, just I didnt care for them as much as I thought I would, and I went back to my JBL 2441,s!

I am going to try them out again, and If they work Ill use em, but If they dont give me what I want, I think Ill sell them off!

Conversely, I have heard the 4001,s on suitable horns, even last month at a studio, and the way they sound, especially in the upper frequencies pleases me! so, knowing that the 4001 and 4002 use the same diaphragm, I assume it is the magnet that makes the difference in the sound. The 4002 and JBL 2450J have a similar tonality! Of course, after reading the literature about the JBL 1500AL woofer, and how the Alnico magnet has much to do with that woofers lively and energetic sound, I feel its safe to assume this also holds true for compression drivers!

To be fair though, I run my 2441,s up to 7K, and a JBL 2404 takes over from there, and although the JBL,s have their flaws, they sound good, and they have a certain bite that gives the music a crisp sound, especially on things like brass instruments that I like! So, even if you had a horn capable of going flat out to 20K, the 2441 is not a suitable driver for that purpose! But it does have a character!

[Mike Bates]

I've had TAD 2001,4001, 4002 and JBL 2440, 2441, and 2440 with 2445 diaphagm.

The 2440 has the best midrange of the bunch, the 4002 TAD has the best treble extension (without the 2" adaptor IOW used as an 1.5" driver) , and the worst overall of the bunch was the 2440 with the 2445 diaphragm followed VERY closely by the TAD 2001 (way over rated/priced IMO) - this is in a home system -

I ended up settling with the best of both worlds - a 2440 and 2405 combo before I ditched using compression drivers all together.

[johnaec]

Originally posted by Mike Bates
I ended up settling with the best of both worlds - a 2440 and 2405 combo before I ditched using compression drivers all together. What's your preference for high frequency reproduction now?

John

[Mr. Widget]

Originally posted by sa660
What should I go for?
I am in a position to choose between a pair of JBL 2440 and a pair of TAD4001 for an exchange with a single westrex electric compression drivers.

Originally posted by Mike Bates

The 2440 has the best midrange of the bunch.....
Re: No Contest

Originally posted by whgeiger
TAD TD4001 wins when mounted on an appropriate horn.


Originally posted by paragon

I am a JBL Lover, but the TAD is the best you can buy
(for a lot of money) !!


Well I guess it's definitive then.:hmm:

I guess you will have to decide for yourself. I would suggest you give the 4001s a listen on some 2350s, 2397s, or better yet the TH4001s.

Widget

[scott fitlin]

Originally posted by Mr. Widget
Re: No Contest



Well I guess it's definitive then.:hmm:

I guess you will have to decide for yourself. I would suggest you give the 4001s a listen on some 2350s, 2397s, or better yet the TH4001s.

Widget I have heard the 4001 on the TAD maple wood horn designed expressly for the 4001 driver, and it really does sound sooooooooo clear and smoooooooth, and NOOOOOOOO distortion, its that good, even though I do love my JBL 2441,s!

to do this driver/horn combination is a TON of money, but it is the best!

[PSS AUDIO]

Good morning to all of you!

I am a 2441 listener as I have a pair of modified 4350.

I will not discuss about TAD drivers as I do not know them and from what I read and understand they will perform better than a 2440-1 as a single driver.

Let’s come back to the 2441.

I am listening at 4350 since 2 years from now and I must say that the mids were hard and noisy, unpleasant.

After setting a lot of “things” I achieved something pleasant and very smooth (ask Scott about it).

I was not 100% happy, as, from time to time, depending of the recording, I still had an arrow in my ears and this was very harmful.

I thought that the 2441 were responsible of the fact as I heard similar paining frequencies with other speakers (same an other amplifiers) still with the same recordings.

To make a long story short, we use an ON-SEMI (formerly MOTOROLA) MJ15032 transistor in the class A stage and MJ15032-33 as drivers.

I replaced the MJ15032 in the class A stage for a Sanken 4883 driver (as I have no more PNP drivers from Sanken I was unable changing the driver stage).

Guess what?

Out of 80% of pain disappeared on those recordings…

I am 100% certain that it will disappear while changing the driver stage.

What does it mean?

It means that some harmonics are responsible of the softness(this is known since decades).

This confirms that the amplifier is responsible of all our headaches, as usual.

With a “poor” amplifier the TAD will sound better as this driver is inferior to the 2441 as I think that TAD drivers rubs some harmonics.

With a “good” amplifier I think the 2441 (1K-8-9K) will outperform all TAD drivers!

[Mr. Widget]

Originally posted by PSS AUDIO


I will not discuss about TAD drivers as I do not know them...


With a “poor” amplifier the TAD will sound better as this driver is inferior to the 2441 as I think that TAD drivers rubs some harmonics.

With a “good” amplifier I think the 2441 (1K-8-9K) will outperform all TAD drivers!

I do have both the TAD 4001 and the JBL 2441 (with fresh diaphragms) and have listened to both extensively. In my comparisons I found the most important difference to be the additional detail the TAD brings to the music. I found this to be more significant than the extra bandwidth. The level of detail approached the electrostatic panels I have owned. Even though I really enjoy the dynamic sound of compression drivers on horns, almost all of them have tended to mask the inner detail (for lack of a better term) on my discs.

I certainly can't say for sure as I haven't had the pleasure of listening to your speakers, but what you are describing sounds like classic diaphragm fatigue. When did you last replace your 2441 diaphragms? With your "good" amplifier it might improve even further with fresh diaphragms.

I fully agree with Mike, that if he prefers the sound of a 2440, that it is the best compression driver for his use, but before you jump to the conclusion that the 4001 is a euphonic device that masks deficiencies in "poor" amps, you should probably try to borrow a pair of 4001s and give them a listen. With your "good" amplifier, you may discover even more to enjoy in your favorite albums.

Widget

[PSS AUDIO]

Originally posted by Mr. Widget
When did you last replace your 2441 diaphragms? With your "good" amplifier it might improve even further with fresh diaphragms.
Widget

I bought the speakers as is and I never changed the diaphragms!

I thought they were responsible, but as I heard the same on high-end speakers (same and different amplifiers), that is why I left my 2441 as is.

By changing the diaphragms, the speakers will certainly sound even better.

Where can I found some in Europe?

As I must ship a "good" amplifier to Scott he can compare his 244x and his TAD 400x and let us know...

[Mike Bates]

Originally posted by johnaec
What's your preference for high frequency reproduction now?

John

I'm using a closely spaced pair of Audax (Harman) PR170MO 6.5" pro wide-range midrange drivers 250-6K on an open baffle in place of the compression drivers. Wired in parallel they are around 106 db sensitive with a watt - sound is even smoother and more detailed than the 2440 in round tractrix horns - plus no crossover 250-6k. In an offset MTM position is the inexpensive Eminence APT80 tweeter with a rear firing slightly modified LeSon TLC1.

This combo is very dynamic and 'fast' sounding (much like the TAD 4001 but with wider range and more "life-like mids) yet doesn't have the fatique I hear with all the compression drivers I have tried to live with.

[Maron Horonzakz]

Yuri.......Im sorry to tell you the 2441 performance cannot match the TAD 4001. Drop a 2450SL diaphram into the 2441 & listen to the pain go away. The aquaplas coating on that diaphram (2450SL) smooths things out & is as sweet sounding as the aluminum but without the pain. But the 4001??? Ahhhhhhh. I think the 5 slit phazing plug has something to do with it.

[johnaec]

Originally posted by Mike Bates
...This combo is very dynamic and 'fast' sounding (much like the TAD 4001 but with wider range and more "life-like mids) yet doesn't have the fatique I hear with all the compression drivers I have tried to live with. Interesting. Thanks for the info.

John

[PSS AUDIO]

Originally posted by Maron Horonzakz
Yuri.......Im sorry to tell you the 2441 performance cannot match the TAD 4001. Drop a 2450SL diaphram into the 2441 & listen to the pain go away. The aquaplas coating on that diaphram (2450SL) smooths things out & is as sweet sounding as the aluminum but without the pain. But the 4001??? Ahhhhhhh. I think the 5 slit phazing plug has something to do with it.

2441 is NOT paining anymore unless with some single frequencies with very particular recording (imagine a whip in the ear)!

Since my last modification this whip almost disappeared.

Amplifier is responsible of this pain in the ear and it means that all those “new” drivers have been “modified” to fit with actual amplifiers (as the amplifier is hard, lets rub what is bad with the drivers/diaphragms)…

Read what Scott said about the smoothness of the amplifier and you may then have an idea why I say that 2441 sounds so mild, like sugar in your throat with “millions” of itsi pitsi tiny details…

Lets make a test!

Everybody knows or heard “The Girl From Ipanema” (Getz/Gilberto) original recording from Verve. If not try to get it and listen to it.

There is some piano with some right hand notes.

By 3’48 minutes there is a small piano solo.

Is it a mechanical or an electric piano?

Depending of the quality of your driver and/or amplifier it will change from one to the other!

Guess witch is the good one!

[Figge]

isnt TAD = Pioneer/Exclusive?

so your saying pioneer is better than JBL? :)


dammit! and i just sold my HPM-70:s for 80 bucks!

[Figge]

Originally posted by paragon
the TAD goes flat to highest frequencies, while the JBL
"oszillates"


well flat isnt allways good! i prefer some curves!:)

[whgeiger]

The following notes provide information germane to the subject of this thread. WHG

1) BNL
Yes! TAD drivers have BNL written all over their designs.
For those interested, his son has produced the following web page in his honor:

Bartholomew Nicholas Locanthi II (1919-1994)
http://www.sabl.com/~bart/bnl2/index.html

2) Be
Aquamarine and emerald are precious forms of the mineral beryl, [Be3Al2(SiO3)6] from which beryllium (Be) is extracted.

The acoustical superiority of beryllium as a diaphragm material can be clearly seen when its mechanical properties are compared to those of titanium (Ti) and aluminum (Al)

For a given diaphragm size and geometry:

a) Sound Velocity
(for longitudinal waves),
determines at what frequency the first breakup mode occurs.

[Be] 12,890 m/s
[Al] 6,420 m/s
[Ti] 6,070 m/s

b) Density
determines moving mass for a given diaphragm size

[Be] 1.85 g/(cm^3)
[Al] 2.70 g/(cm^3)
[Ti] 4.51 g/(cm^3)

c) Rigidity Modulus
determines how well the diaphragm resists deformation (stiffness)

[Be] 132 GPa
[Al] 26 GPa
[Ti] 44 Gpa

3) Phase Plug
Each annular slit in a phase plug is designed to suppress a specific radial standing wave mode that occurs in the front cavity of a compression driver. Such modes occur because acoustic energy must flow radially away from a larger diaphragm into a smaller horn throat so that the desired compression ratio may be achieved. The wider the bandwidth of the driver, the more silts are required to suppress the additional modes of increasing frequency. For those interested in phase plug design, the following work of Bob Smith should be studied:

Title: An Investigation of the Air Chamber of Horn Type Loudspeakers
Author: Bob H. Smith
Publication: ASA-J, Vol. 25, No. 2, pp. 305-312, Mar-1953
Affiliation: Division of Electrical Engineering, University of California
URL: none
Abstract: The front air chamber design is treated as a boundary value problem which yields a solution of the wave equation for the general case in which the horn throat enters the air chamber in a circumferentially symmetrical manner.
The following specific cases are analyzed: (1) the case in which the horn throat enters the air chamber by means of a single orifice, (2) the horn throat enters the air chamber by means of a single annulus of radius [r] and width [w], and (3) the horn throat enters the air chamber in [m] annuli of radii [r1],[r2],...[rm] and widths [w1],[w2],...[wm].
The analysis reveals that the radial perturbations caused by the horn throat excites higher order modes. At the resonant frequencies of these modes the horn throat pressure becomes zero and the loudspeaker does not radiate. By suitable choice of annulus radii and widths the first [m] modes may be suppressed and the corresponding nulls in the output pressure eliminated.

Title: An Application of Bob Smith's Phasing Plug
Author: F. M. Murray
Affiliation: Jamse B. Lansing Sound, Inc.
Publication: AES-P, No. 1384, Cnv. 61 (1978-11)
URL: http://www.aes.org/publications/preprints/search.html
Abstract: The war of the phasing plugs still rages after more than 25 years. Compression driver phasing plugs have vacillated between annular rings, salt shakers, teardrops, and now radial slots again. When Bob Smith provided simple design criteria for optimization of the annular ring type, little did he realize how studiously he would be ignored. His design is now incorporated into a large compression driver capable of operating to the high frequencies where this design is important

4) PWT
To measure frequency response of a driver, a plane wave tube (PWT) should be used. Here power response is measured and horn artifacts that mask the true capabilities of the driver under test (DUT) are avoided. For details see the following:

Title: Building a Plane-Wave Tube: Experimental and Theoretical Aspects
Author: Roberto Magalotti
Author: Carlo Zuccatti
Author: Paolo Pasini
Publication: AES-J, Vol. 47, No. 7/8, p. 596, Jul/Aug-1999
Abstract: The primary purpose of this report is to describe the building and testing of a plane-wave tube for measuring compression drivers in an audio laboratory. A new method for testing the tube for undesired reflections was devised, with and without sound absorbing materials. The experimental results show good agreement with the predicted behavior outlined in the AES document on plane-wave tubes, and confirm the predictions on usable bandwidth limits.

Title: Plane-Wave Tubes: Design and Practice
Author: AES Standards Committee
Publication: AES-ID, No. 1id-1991, Rev. Jun-2003
URL: http://www.aes.org/standards/b_pub/aes-1id-1991-r2003.pdf
Abstract: The "AES Recommended Practice — Specification of Loudspeaker Components Used in Professional Audio and Sound Reinforcement" in its 2.2.1 calls for the use of plane-wave tube measurement of horn drivers. Because many variations and results are possible, depending on the details of construction of plane-wave tubes, this document discusses those variations for the purpose of encouraging further experimentation.

[sa660]

To achieve sound the TAD4001 look to please most of your JBL fans.

I am very thankfull for all your comments.

I just need the right Horn for the TAD4001.

Regards,

[still4given]

Is it possible to get drawings for those Westlake horns? I would like to try building a pair.

Thanks, Terry

[whgeiger]

Originally posted by sa660
.

I just need the right Horn for the TAD4001.

Regards,

If you send me an e-mail I will send drawings for the "right horn".

[email protected]

In the meantime, here are some examples:

http://members.aol.com/araiyuichi/

Regards,

WHG

[Don McRitchie]

This gets mentioned every so often, but it has been a while so that a refresher is probably in order. The similarities between the 375 and TAD 4001 are no accident since they were designed by the same person - Bart Locanthi. This is the BNL that WGeiger referenced in a previous post.

Bart Locanthi was responsible for engineering at JBL for two decades. He started as a consultant in 1950 to fill the engineering void that resulted from Jim Lansing's death. He later joined the company full time as Vice President of Engineering in 1960. Unfortunately, there was a falling out with the new management of JBL when Bill Thomas sold the company. Locanthi left the firm in 1970 to first join Altec, and then Gauss, before ending up at Pioneer in the mid 70's.

At Pioneer, Bart was responsible for the HPM series of loudspeakers. This is why the first speaker in that series, the HPM100, bore a striking resemblence to the L100. To Figge, you should of held out for more than $80 for your HPM 70's since there is actually some demand for that series.

Pioneer considered it quite a coup to gain Bart's services since JBL was the single most revered loudspeaker brand in Japan. Pioneer gave Bart virtually unlimited resources to build the highest performing loudspeaker components possible for the first TAD product line. I have been told anecdotes of his being treated like royalty when visiting Pioneer's Japanese headquarters during the development process. At meetings, Pioneer's management would hang on every word and transcribe his comments as absolute orders to be followed to the letter.

The first TAD compression driver was specifically designed as an evolution of the 375. Bart had done the design work on that driver in 1953. It was pretty much a copy of the WE394, but replacing the field coil motor with an Alnico PM. The new TAD driver took the basic motor structure from the 375 and introduced berylium as a diaphragm material and changed the phase plug design to accommodate the extended bandwidth of the new diaphram material. The bass drivers were similarly derrivative of JBL designs, with the TAD 1602 borrowing from the LE15A.

The primary proponent of TAD in the US has been George Augspurger and his studio design firm, Perception Inc. George was also a previously long term employee at JBL and an associate of Bart Locanthi. George has designed most of the large format monitors that use TAD components for some of the highest profile studios in the industry. He mainly specs TAD due to the extended response of the compression drivers that allow for two-way deisgns. However, if this is not a requirement, he has used JBL compression drivers. Recently, he developed a hybrid monitor that used 4-12" JBL drivers from the LSR-32 for the bottom end.

[Figge]

thanx Don!

the wealth of knowlage on this board is amazing!

as for the HPM:s...i was glad just to get rid of them

however i had a pair of hpm-30 in my youth wich i liked very much! im still holding an eye open for those...dont see em to often on the used market...however they would be squished by a pair of 4301 any day.

[Oldmics]

Is there any information regarding what Mr.Locanthi was involved in during his stay at Gauss?

Oldmics

[scott fitlin]

Didnt Edmond May also wind up at Gauss?

[Don McRitchie]

Ed May went to Cetec Gauss first in 1969, where he was responsible for developing their line of loudspeaker components. Around that time, Bart moved from JBL to Altec. Bart was responsible for Altec finally adopting cast magnet structures for such drivers as the 416-8B and 515. He was also responsible for the 616-8A 15" Duplex, which is one of the most under-rated Altec drivers made. Unfortunately, Bart was no more successful with Altec management than JBL and they soon parted ways. His friend Ed May was responsible for getting him a position at Gauss. However, his position there was associated with electronics and not loudspeakers.

[Niklas Nord]

Can the TAD 4003 handle as much abuse as the JBL 2451 for example....

[Mr. Widget]

Why would you want to abuse such a fine driver?

It is rated at 60 watts above 600 Hz and the 2451 is rated at 100 watts above 500 Hz. The TAD is 1 dB more efficient but it isn't really meant to make your ears bleed.

If you simply want the Hummer of drivers try a JBL 2482 or 2485. They will take 120 watts above 300Hz.


Widget

[Niklas Nord]

A, offcouse i would not like to abuse it.
What i ment was if it is as capable as the 2451 when
it comes to SPL, distorsion and so on... I like to play
good damn loud :D and just wanted to know if the
TAD is capable just like the 2451.

Mr Widget, where do you cross the 1500AL to your
4003? Somewhere 800hz ? I guess it would be hard
to blow the 4003 in that high crossing!

[scott fitlin]

TAD compression drivers are pretty durable! Honestly, if your playing them loud enough to blow them I dont think you would be able to stay in the room, cause its gonna be loud! As long as your properly powered and crossed over, you will have enough level long before you reach the thermal or mechanical limits of the driver.

:)

[paragon]

Take both and hear both !!

Eckhard

[Mr. Widget]

Originally posted by Niklas Nord


Mr Widget, where do you cross the 1500AL to your
4003? Somewhere 800hz ? I guess it would be hard
to blow the 4003 in that high crossing!

Hi Niklas,

I am crossing over around 650 Hz with a 24dB slope. (TAD recommends 12dB min. slope) I have been accused of liking it loud. I really doubt I have ever given the 4003s more than 1 watt (112dB m). 60 watts would be over 129dB. If you want it that loud or louder you WILL damage your hearing.

I do not know the distortion figures, but the 4003 will have significantly lower distortion at any power level.

Widget

[Niklas Nord]

Someone give me some 4003´s and some 1500AL please...

Mr Widget, do you feel there could be a midrange driver between
your 1500AL and the TAD driver? Perhaps a 2020 or 2123..

[Mr. Widget]

One of the main reasons I was excited about using the 1500AL was that it sounds good at the higher frequencies. I would love to use only the 4003 and the 1500AL in a true two-way. I agree with Mr. Greg Timbers here about the two way being very near ideal. As you add drivers you loose coherency.

Designing a system based on these two exceptional drivers allows you to almost have the two way, and in fact for some music they would be fine. However I really do think a super tweeter above 10KHz would add a bit of air that is missing. I hope it doesn't have unintended consequences and damage some of the incredible coherency that I am enjoying. I do let the 1500AL run out on it's own with no high pass filter on it. The Sub1500 does add to the low bass fundamentals. I guess I am currently running a 2.5 way. With the addition of a supertweeter it will be a 3.5. Adding an additional midbass driver would, in my opinion, cause more harm than any possible slight benefit in mid bass punch.

Widget

[Niklas Nord]

Thats one of the strenghts of my K2, there is so much energy in
the whole range, instruments sound so realistic when it comes to
fysical strenght. Drums has alot of energy...

Yes, it´s great with 15 inch driver all the way up, alot of energy
and punch in the whole range.

[scott fitlin]

This is exactly why I stay with a 2 way plus tweeter full range! More xover points screws up phase, and simple two ways produce remarkable coherency, and together sound!

You get into 4 way full range, and the music can sound somewhat disassembled. The ranges dont always gel togather seamlessly, its much easier to get 2 way plus tweeter to work while maintaining a seamless sound!

My full range crossoes over at 750hz 18db butterworth from the 15,s into the 2441,s and at 7khz into the 2404, soon to be 2405! The tweeter does give that airy sound the horn and comp driver just are not capable of!

:)

[Zilch]

Originally posted by Mr. Widget
I agree with Mr. Greg Timbers here about the two way being very near ideal. As you add drivers you loose coherency.It's likely one reason everybody seems to like 4430 so much.

We need to explore ways to get more high frequency extension outta them, maybe, without adding a UHF driver.

Mackie 1400i has an "Air" option for constant directivity horns. Been meaning to hook that up and see what happens. The limitation is in the 2425/6H, though, no? Even with boost, it's not gonna go ultra high?

[Mr. Widget]

Originally posted by scott fitlin
The tweeter does give that airy sound the horn and comp driver just are not capable of!


Yeah, I am afraid after experimenting with these TAD drivers that there is little hope of getting the very finest quality of high frequency reproduction without adding a UHF device if you are going to use a compression driver for the mids and highs.

Zilch,

I do not believe any of the 1" 2425, 2426, 2421, TAD 2001, or any other compression drivers can reproduce delicate UHF with finesse and be capable of reproducing mid frequencies. Based on my recent experiments and according to JBL literature 1" vs. 2" drivers do not inherently have increased HF response. JBL also acknowledges the superior HF response of the TAD beryllium diaphragms. From my experiments with EQ you can get a linear 20KHz response from the TAD drivers, but it just isn't of the same quality as a dedicated UHF device.

Widget

[scott fitlin]

There is this one tweeter I would love to try if they werent so darn expensive! The TAD ET-703!

Looks to be right up the Hi Fi alley, UHF response, super light Be diaphrams, and cobalt magnet, and looks like a slot with out the phase plug!

Alas, you can get a brand new pair of JBL 2405,s for less than one of these.

Still.............:hmm:

http://www.tad-pioneer.com/pna/product/detail/0,,2076_4213_37106_tab=B,00.html?compName=PNA_Prod uctDetailComponent

[Alex Lancaster]

I had seen them (in paper), but had no idea of the price; Who buys them?, forget the 2405´s, You can get a couple of complete 4430´s for that; They would look a lot better if they hid the 4 ugly screws.

[scott fitlin]

I have never actually heard them, they are supposed to be good though, really good.

The allen screws give it a kind of industrial look, I could live with it. Ill bet if you heard them, and loved them, so could you.

I did say they were expensive. I had thought about getting them, and I have a freind who is TAD authorized, and still, they are just too darn expensive!

Truthfully, I dont really think about them that much though, as JBL tweeters are really good, and have always satisfied me. I find one really nice thing about the price of the TAD tweeters, it makes buying six JBL 2405,s brand new almost painless!!!!!!!! :D. The real reason I dont fret much over these is the fact that JBL,s are terrific, I have heard them everywhere, I know what I can get out of them, and I know they work.

The TAD, well, never heard them, dont know exactly what they sound like! I have six TAD-4002,s and dont love them, prefer the JBL 2441. So, its like that, for me, anyway!

[Mr. Widget]

Yeah, that is the UHF device I have my eye on. I have heard them and they are quite good. Of course one could easily make the argument that they are ridiculously expensive, but it would be difficult to make that statement after buying a pair of compression drivers and horns retailing for $9K. At that point what is another two?

As far as the aesthetics... the screws look fine in person. The machined aluminum horn is so eye catching you really don't notice the extra little shiny bits.

I need to rob a bank and then I will get a pair to try out with my system.

Widget

[scott fitlin]

I have seen them, at the AES show, and I agree they look good.

From what Im told, they have an even more delicate sound than the JBL 2405, which some tell me Im am nuts to put in my place over the 2404,s! But I can hear the difference, so I do it to please myself!

The TAD price wouldnt be so bad to me If we were talking about two tweeters, but at six units, its just too costly.

Of course, if they are too delicate sounding they might be too obscured, sonically, by everything else going on im my place! JBL has great cut through, and clarity, and maintains a sound that is distintcly audible as a JBL tweeter! Another reason I choose to remain JBL for this range of my system. I have heard ribbon tweeters that I thought were absolutely stunning sounding, very open, airy, very fast transients, but so delicate, but I know they would get completely lost in my application, and they are also sensitive to dirt and dust, something the Eldorado has its own brand of! Carbon Dust, we make our own!

:eek:

However, I could see the tonality of the TAD tweeters working very well with the TAD compression drivers you already have!

Mr. Widget, please dont rob a bank! California is not too forgiving to bank robbers, and TAD tweeters are not worth what you will have to endure in a Federal Penitentiary!

A little advice though, should you decide to do it anyway, and happen to get caught, whatever you do in prison , DO NOT BEND OVER FOR THE SOAP!

:rotfl:

[Earl K]

Originally posted by scott fitlin
The tweeter does give that airy sound the horn and comp driver just are not capable of!
-------------------------------------------------------------------------------------------------
I. disagree !
- Tweeters are the easy way out when it comes to achieving a balance between the respective MF - HF ranges of dynamics and finesse .

- The considerably harder, but more sonically homogenous way, is through the selective use of capacitors as passive dynamic compressors . This is done in Mastering Studios all the time with MultiBand Dynamic Compressors .

- Obviously: There is; Nothing easy or "mapped out" or "off the shelf" about this approach - but it is hugely rewarding and worth the effort .


Originally posted by Mr Widget
Yeah, I am afraid after experimenting with these TAD drivers that there is little hope of getting the very finest quality of high frequency reproduction without adding a UHF device if you are going to use a compression driver for the mids and highs.
--------------------------------------------------------------------------------------------------


See my above comments for where I stand on this .

<> Earl K:)

[Mr. Widget]

Earl,

How would "the selective use of capacitors as passive dynamic compressors" create a more effortless, delicate sound quality than using a White 4400 with a gentle +6dB bump to achieve a linear response to 20KHz?

Widget

[Earl K]

How would "the selective use of capacitors as passive dynamic compressors" create a more effortless, delicate sound quality than using a White 4400 with a gentle +6dB bump to achieve a linear response to 20KHz?


- Any EQ has one or two types of caps ( filters ) that one is obligated to listen to , once those caps are put into the signal path. Every cap ( & its' dielectric type ) has it's own sonic signature that can be used for "Good or Evil".

- Some caps are more complementary to certain signal ranges compared to other types.

- I haven't ripped apart a 4400 to see or understand where its' sonic bias may lay .

<> Earl K

[Tom Loizeaux]

Remember, many people say there should not be a crossover in the vocal range. Most 2-way systems require a crossover in there somewhere.
Hey, my 2-way Altec Valencias sound very good, but my JBL 4343s go deeper, have a smoother midrange, and go higher too. I think the secret of the 4343s is the 10" mid. The 15 handles the low end without needing to track the vocal material, and the compression driver doesn't need to cover the vocal material, but is left to add the clarity and top end, helped by the 2405 of course. I suspect fewer crossovers are a good thing, but the drivers need to be able to cover the required range without compromise.

BTW, I count a subwoofer, a 15, a compression driver and a slot tweeter as approaching a 4-way system.

Tom

[Robh3606]

Wow what a thread!


"From what Im told, they have an even more delicate sound than the JBL 2405, which some tell me Im am nuts to put in my place over the 2404,s! But I can hear the difference, so I do it to please myself!"

Hello Scott before I did the 4344's I was trying different drivers as I was thinking about swapping the 2405 and using a 2404. I found the same thing. Not sure why but the 2405 sounded more delicate more detailed to me too??? Can't figure that one out unless it has to be with the 2405's focusing things a bit more???

Hello Zilch

"We need to explore ways to get more high frequency extension outta them, maybe, without adding a UHF driver.

Mackie 1400i has an "Air" option for constant directivity horns. Been meaning to hook that up and see what happens. The limitation is in the 2425/6H, though, no? Even with boost, it's not gonna go ultra high?"

There is only so much you can get out of them. Take a look at the distortion graphs on the 4430. At the high end you can see the numbers going up with frequency. If you looked at a 3/4 way monitor like a 4333 or 4343 that doesn't happen. Those 1" drivers just run out or steam and what is up there is not as clean as a dedicated driver. So you trade phase issues for linearity to use the 2405's.

"As far as the aesthetics... the screws look fine in person. The machined aluminum horn is so eye catching you really don't notice the extra little shiny bits."



Hey Widget

Classic Audio Reproductions uses them. They sound nice and do look good in person. I would have to do a side by side to see just how much better they are though. That's some bucks!! All the TAD is!!!!

http://www.classicaudiorepro.com/

"Earl,

How would "the selective use of capacitors as passive dynamic compressors" create a more effortless, delicate sound quality than using a White 4400 with a gentle +6dB bump to achieve a linear response to 20KHz?

Widget"

I am running charge coupled mylars with polpropylene bypasses on my 2344 for the compensation. The extension is not any more but the what's there is liquid sounding. Very smooth not harsh and good bite when there should be. It does improve things at least for that combo.

Hello Tom

"I think the secret of the 4343s is the 10" mid."

I agree. In both system I use a 10" in the vocal and instrumental clarity is really excellent.

Rob:)

[scott fitlin]

Rob;

Hello Scott before I did the 4344's I was trying different drivers as I was thinking about swapping the 2405 and using a 2404. I found the same thing. Not sure why but the 2405 sounded more delicate more detailed to me too??? Can't figure that one out unless it has to be with the 2405's focusing things a bit more???

I have always thought the 2404,s plastic horn has something to do with things, and the 2405 is machined aluminum. I just know the 2405 will be a really good tweeter to take my full range stacks out to 20K!

It also probably has as much to do with the geometry of the horns too.

All I know is that the 2405 will also look as good as it sounds perched on my stacks!

:cool:

[speakerdave]

Originally posted by Tom Loizeaux
Remember, many people say there should not be a crossover in the vocal range. Most 2-way systems require a crossover in there somewhere.
Hey, my 2-way Altec Valencias sound very good, but my JBL 4343s go deeper, have a smoother midrange, and go higher too. I think the secret of the 4343s is the 10" mid.
That's certainly part of it. I think the reason the voice range is so important is that the human ear/listening/decoding evolved to pick up nuances in the voice that reveal another's intent. A lot of this information would be generated by various tensions in the body's sound making and shaping apparatus. The fundamental note may undergo slight changes in elevation, and the overtone combination would be altered. The critical area would go beyond the range of the voice fundamentals. Our listening is very sensitive to anamolies in this range.

I think one reason the LSR 32 works so well is that the cone midrange runs from 250 hz to 2.2 khz. That parts out some of the voice fundamental region on the low end but includes some of the first and second voice range overtones on the high end.

David

[Zilch]

Originally posted by Robh3606
Those 1" drivers just run out or steam and what is up there is not as clean as a dedicated driver. So you trade phase issues for linearity to use the 2405's.I'm thinkin' a retro Be diaphragm, maybe, or another tweak that would extend the range upward.

NOTE: Y'all what are swappin' out them 2404's for 2405's should be aware that there's only ONE certified environmentally conscious means available to responsibly dispose of them nasty plastic 2404's. Contact the Zilchster for the requisite packaging and shipping information....

:D

[scott fitlin]

quote:
--------------------------------------------------------------------------------
Originally posted by Robh3606
Those 1" drivers just run out or steam and what is up there is not as clean as a dedicated driver. So you trade phase issues for linearity to use the 2405's.


Last week, I got out one of our old tweeter devices! The Altec 808-8B, with a tangerine phase plug, mounted on a Community horn.

This 1 inch always sounded good to me, and it still did, and does, but the thing I noticed, even though it was nice sounding, is it didnt have the high frequency snap of a dedicated tweeter! It went up, the extension was there, but no matter what I did, it just isnt a tweeter, its a 1in comp driver. The highs out of this thing sounded smooth, and open, so to speak, but it lacked the detail, and definition that a tweeter produces at frequencies over 10K. To be blunt, it sounded like a 1 inch, not a tweeter!

So, after this experience, I decided the only way to improve my full range highs, is to replace the JBL 2404 with a BETTER JBL tweeter, the 2405! What a tweeter does, I like!

Jus my 2 cents worth!

[Zilch]

Originally posted by scott fitlin
quote:
So, after this experience, I decided the only way to improve my full range highs, is to replace the JBL 2404 with a BETTER JBL tweeter, the 2405! What a tweeter does, I like!They be different, is all, the major difference being the dispersion characteristics:

2404 is 100° H X 100° V from 3 kHz to 20 kHz.

2405 is:

140° H X 40° V at 10 kHz
90° H X 35° V at 16 kHz
65° H X 30° V at 20 kHz

SO, it depends on if you're dancin' or meditatin' type listener, maybe.

"Like" factor is the most important parameter in all of this, I've found.... :p

[scott fitlin]

Originally posted by Zilch
They be different, is all, the major difference being the dispersion characteristics:

2404 is 100° H X 100° V from 3 kHz to 20 kHz.

2405 is:

140° H X 40° V at 10 kHz
90° H X 35° V at 16 kHz
65° H X 30° V at 20 kHz

SO, it depends on if you're dancin' or meditatin' type listener, maybe.

"Like" factor is the most important parameter in all of this, I've found.... :p The post your quoting me on is me describing the difference between an Altec 808-8B 1 inch compression driver, used as a tweeter vs a JBL tweeter, the 2404! They be VERY different from each other!

As for the differences between the 2404 and the 2405, I think the horns on each make a considerable sonic difference, more than just dispersion characteristics.

What one likes is the most important factor, though!

:)

[Robh3606]

"As for the differences between the 2404 and the 2405, I think the horns on each make a considerable sonic difference, more than just dispersion characteristics.


You know it reminds me of the differences between the 2344/2307+2308. Almost the same dispersion charateristics and diferences. What Ian has said the 2344 puts it all over the room where the 2307/2308 has a more defined and focused listenning area. As such I wonder if some of the micro dynamics gets lost or dilluted in the wide angle horns between the lower spl at your listenning position and the room reflections clouding things up a bit. On axis either combo is not the same just one more of those subtle differences we get to choose.

"What one likes is the most important factor, though!"

Yeah I would say so.

Rob:)

[Mr. Widget]

Originally posted by scott fitlin
Hey Widget

Classic Audio Reproductions uses them. They sound nice and do look good in person. I would have to do a side by side to see just how much better they are though. That's some bucks!! All the TAD is!!!!

http://www.classicaudiorepro.com/


As for the differences between the 2404 and the 2405, I think the horns on each make a considerable sonic difference, more than just dispersion characteristics.


Yes I heard a pair of the Classic T-1s some years ago. They were very nice, but I wasn't sent to audio nirvana... I was disappointed in their resolution of micro detail. In fact it was this experience that made me hesitant to spend the ridiculous amounts of money required for the TAD drivers.

Having heard these components in multi-amped systems without the Classic Audio Reproduction's passive crossover I have become quite smitten with their performance.

As for the 2404 vs. 2405, I think the horn's loading on the diaphragm is the issue and not the dispersion characteristics or the material that the horn is made of. Remember that the 077 used a plastic wedge for the center of the horn as opposed to the solid aluminum wedge used on the 2405. There are probably those that think the two sound different, but I am not one of them.

Widget

[scott fitlin]

You make a good point Widget, however, when I refer to the 2405, and I have heard these in top grade nightclubs as well as studio monitors, and top flight JBL consumer speakers, the ones I hear in clubs have always been the black aluminum phase plugs! So, I already have known for years I like the 2405 pro tweeter for full range apps.

Setup properly the slot sounds good. What I do know and acknowledge is that the 2404 and 2405 do not sound the same! I seem to prefer the slot, and I would say your observation of the difference in sound being due to the differences in each horns loading on the diaphragm makes sense.

:)

[jlac4]

I was very interrested by reading this very good post
I cannot afford to buy a TAD TH 4001
THUS I'm looking for someone having the plans of this nice woodhorn
I like to work by myself and should be very proud to built one
thanks for your cooperation