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Guido
01-07-2009, 12:42 PM
I finally finished the modification of the 4435 network for the use of a TAD2001 driver and must say it was worth the work.
Following I'll post the first real 2426 (Aquaplas coated) - TAD2001 comparison at our forum.
Finally I'll advice you how to modify the network.

Feel free to ask questions. It's not to hard to do though :)

Guido
01-07-2009, 12:50 PM
First 2426AQPL vs TAD2001 on 2344 on Axis
Second 2426AQPL vs TAD2001 on 2344 30°

SPL isn't normalized to 1W/1m :o: My mistake, but who cares? The drivers are more or less of same efficiency.

Guido
01-07-2009, 12:55 PM
First 2426AQPL on 2344
Second TAD2001 on 2344

The TAD goes way high with incredible nice waterfall.
The 2426 isn't bad either ;)

Guido
01-07-2009, 01:06 PM
Impedance Graphs
Blue 2426AQPL
Red TAD2001

TAD shows similar impedance as 2426 J. Will be compensated with a crossover modification.
Lower Fs on TAD because of mylar suspension and bigger diaphragm.

Guido
01-07-2009, 01:19 PM
The schematic shows L-Pad values for my prefered adjustment:
2426AQPL from earlier setup
TAD2001 from actual listening sessions

Rpar needed to be changed due to higher impedance of TAD2001
Resonance circuit (40uH) no longer necessary
Compensation C changed a bit
Slight L-Pad adjustment

Thats all ;)

Voltage drives are with real impedance, thus a bit wavy.

Schematic is of course simplified as I use CC crossovers.

Guido
01-07-2009, 01:25 PM
The real response is very similar or even identical to the predicted response :D

As said, this is my prefered L-Pad adjustment before (2426AQPL) and after (TAD2001) modification.
Still the L-Pads are in use to make subtle changes.

Stop lamenting about TAD prices. Go get a pair. The TAD graph looks slightly smoother but can't really show the improvement. It's incredible how this dramatic 4435 low end combined with the TAD top end sounds. Uuuuhhhh :bouncy:

Robh3606
01-07-2009, 01:26 PM
Hello Guido

Great! Thanks for posting it. Do you have the waterfalls for the finished systems??

Rob:)

Guido
01-07-2009, 01:30 PM
That's all for now.

Rob I didn't plan to measure new Waterfalls. What do they really tell us? The TAD's will only bring a slight improvement (measured!).

I trust my ears now and simply love the result :)

If you guys do need some more info, just ask and I'll try to answer.

Guido
01-07-2009, 01:38 PM
Too bad those TAD dias doesn't fit into JBL's. The're a bit bigger in diameter :biting:

Robh3606
01-07-2009, 01:44 PM
Hello Guido

Well you posted them without compensation so I figured you would run them as the speakers would be used. As far as what they tell us?? The cleaner the CSD the better, how audible are diferences?? Just my curiosity to see if there are differences between the drivers asside from the obvious.

What are the DCR's for your Inductors?? It would help if you could post them so if someone else decided to give it a go they have them.

Glad you are happy with them. The top end definately looks improved by the swap.

Rob:)

Guido
01-07-2009, 01:53 PM
Well you posted them without compensation so I figured you would run them as the speakers would be used. As far as what they tell us?? The cleaner the CSD the better, how audible are diferences?? Just my curiosity to see if there are differences between the drivers asside from the obvious.

The only reason for posting is that the people at TAD make such a mystery about specs (I hate it). So I wanted to have the raw TAD2001 specs shown.
BTW not raw but with 22uF cap in series.



What are the DCR's for your Inductors?? It would help if you could post them so if someone else decided to give it a go they have them.

They are close to the original DCRs. If someone really go this route I'll measure them. Promise!


The top end definately looks improved by the swap.

See this is the problem with posting graphs. The REAL improvement can't be measured.

Mr. Widget
01-08-2009, 12:19 AM
See this is the problem with posting graphs. The REAL improvement can't be measured.Exactly... and not just in comparing JBLs and TADs. Yes, we want a flat or nearly flat response curve, low distortion measurements, clean impedance plots etc., but actually listening to these things is a real eye opener. :blah:

I am not familiar with the sonic characteristics of the 2001, but knowing the 2002, 4001, and 4003... I can well imagine the improvement.

With the bottom end of the 4435, I can imagine that this upgrade could result in a formidable system.


Widget

4313B
01-08-2009, 07:04 AM
See this is the problem with posting graphs. The REAL improvement can't be measured.Understood.

With the bottom end of the 4435, I can imagine that this upgrade could result in a formidable system.No doubt! :yes:

Great work Guido! Very nice. :)

Chas
01-08-2009, 07:39 AM
Stop lamenting about TAD prices. Go get a pair. The TAD graph looks slightly smoother but can't really show the improvement. It's incredible how this dramatic 4435 low end combined with the TAD top end sounds. Uuuuhhhh :bouncy:

I couldn't agree more Guido, my experience with TD 2002 has been nothing short of amazing. One thing I did note was a particularly long break-in period. They were good early on and continued to get better over a period of months.

Ian Mackenzie
01-08-2009, 07:42 AM
Interesting but old news

http://www.audioheritage.org/vbulletin/showthread.php?t=12901

There seems to be a a flow of S/H trades of Tad 2001s if you know where to look but I note many Tad 2001 users are using aftermarket dias with preferred results.

The Tad 2002 would appear a more recent design.

Guido
01-08-2009, 07:56 AM
Interesting but old news
http://www.audioheritage.org/vbulletin/showthread.php?t=12901


This old thread helped nobody as there isn't one "how to" information.


There seems to be a a flow of S/H trades of Tad 2001s if you know where to look but I note many Tad 2001 users are using aftermarket dias with preferred results.

Using a TAD with an aftermarket diaphragm is the most stupid thing I can think of :p

Guido
01-08-2009, 07:57 AM
I couldn't agree more Guido, my experience with TD 2002 has been nothing short of amazing. One thing I did note was a particularly long break-in period. They were good early on and continued to get better over a period of months.

Did I miss something Chas?
Did you implement TAD2002's in 4435's?

Chas
01-08-2009, 09:08 AM
Did I miss something Chas?
Did you implement TAD2002's in 4435's?

Sorry if I confused you. At the moment they are in my 4345's. None the less, the effect has been stunning as you have noted in your 4435's.

jblbgw_man
01-10-2009, 05:31 PM
Thank you for posting the information and your findings, this was one mod I was wondering about doing to my 4435's, I would be most interested in your listening tests.

Thannks again:cheers:

Guido
01-11-2009, 08:01 AM
It isn't the better response above 10kHz that I prefer. Yes it is nice to have this extended top end with some instruments. I triangle e.g. sonds essentially different than on the AQPL 2425's, but the main advantage is somewhere else.
The real advantage are the mids. I'm very sensitive to mids (1kHz - 4kHz). I easily find a compression driver sounding harsh in this regions. That's why I cc'd my crossovers and AQPL my diaphragms. But still I heard this "harshness" with certain material (sax e.g.) and at certain volumes. Not only high volumes.

All this is gone now. Up to real club volume these TADs sound clean.

As written, it's worth the cost for sure. BTW: It was the cost and availability factor that let me decide to use the 2001 instead of the 2002.

Mr. Widget
01-11-2009, 11:49 PM
It isn't the better response above 10kHz that I prefer. Yes it is nice to have this extended top end with some instruments. I triangle e.g. sonds essentially different than on the AQPL 2425's, but the main advantage is somewhere else.
The real advantage are the mids. I'm very sensitive to mids (1kHz - 4kHz). I easily find a compression driver sounding harsh in this regions. That's why I cc'd my crossovers and AQPL my diaphragms. But still I heard this "harshness" with certain material (sax e.g.) and at certain volumes. Not only high volumes.

All this is gone now. Up to real club volume these TADs sound clean.This exactly what I heard when Bo went from 2421s to TAD 2002s in his system. For years I made fun of that fog horn... changing the driver made a slight to moderate change in measured response and a significant improved listening response... one that using an EQ just couldn't.


Widget

pos
01-12-2009, 02:08 AM
Very nice Guido, a well documented modification, thank you!

Has anyone tried to plug some Geddes' foam (reticulated foam, 30PPI) in the compression slot yet?

felixx
01-12-2009, 03:23 AM
There are plently of other well respected 1 inch drivers. You might be surprised how good they are.


I know the timbre can't be measured and an electrical responce is not the same with acoustical responce.

It will be very pleased to see a preference list for 1" drivers no matter the price or name,based first on timbre (acoustical responce) and not on the electrical or how much "linear" is the responce.

moparfan
01-18-2009, 11:17 AM
I assume that this work could be applied to the 4430? Doesn't this turn out to be a buttload of money - and wouldn't it be better to just sell the old monitors and just build a new box for the TAD 2001 - 4430/35 inspired update?

Mr. Widget
01-18-2009, 12:07 PM
Doesn't this turn out to be a buttload of money - and wouldn't it be better to just sell the old monitors and just build a new box for the TAD 2001 - 4430/35 inspired update?Well... I'd start anew as I am not a Butt Cheek horn fan or a fan of using 2235Hs up to 1000Hz, but for those who own these speakers, popping on the TAD is completely reversible... TAD used the JBL bolt pattern for the 2001.


Widget

pos
10-09-2014, 03:04 PM
Hi Guido,

Sorry to revive this old thread, but it looks like you finally implemented some TD2002 in your vertical 4435.
How did this driver compare to the TD2001? How did the network and CD compensation differ?
Does the TD2002 have a significantly higher mass breakpoint frequency compared to the TD2001?

I ask this question because someone recently posted a curve of what he claims to be a TD2002 on a 2344 without any passive network or EQ, and the result looks dubious to say the least (no mass roll off?!) :

63373

Mr. Widget
10-10-2014, 01:00 PM
I ask this question because someone recently posted a curve of what he claims to be a TD2002 on a 2344 without any passive network or EQ, and the result looks dubious to say the least (no mass roll off?!) : The posted plot can not be correct. The TAD TD-2002 is an excellent driver, but it doesn't have a rising response which would be required to compensate for the 2344's natural roll off.


Widget

Earl K
05-08-2017, 10:59 AM
Just a topical & timely bump ( for someone else ).

:)