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ngccglp
06-14-2005, 04:41 AM
Hi,

I've seen people adding JBL hi freq driver (2402, 2405 etc.) to horn speakers by connecting a capacitor in series to the +ve terminal of the driver.

May I know:

1. Whether the capacitor in series is performing the freq cut off function

2. If so, may I know the value of the capacitors to achieve 18 khz, 20khz and 22 khz crossover respectively?

Thanks.

johnaec
06-14-2005, 06:49 AM
Why such a high frequency? The 2402 is virtually useless above 18K, and the 2405 barely...

John

Don Mascali
06-14-2005, 07:34 AM
I use 2344A horns and 2426H drivers for HF and have added a 2404 UHF with a 2.2 mfd cap in series. JBL says the minimum impedance for these is 7.2 ohms. I'm not sure what the formulas say as to the "correct" value, but I've tried several values and these sound the best to me.

I like the gradual (6db/octave) roll off as it seems to work well with my horns. I actively cross all of the other points so I don't have the HF roll off compensation for the 2344A/2426H combination which the guys have written tons about in the 4430 thread.

Good luck,
Don M

Mr. Widget
06-14-2005, 09:44 AM
May I know:

1. Whether the capacitor in series is performing the freq cut off function

2. If so, may I know the value of the capacitors to achieve 18 khz, 20khz and 22 khz crossover respectively?


It isn't quite that simple. I single capacitor in series with a speaker will provide a first order cut off... that means you will get a 6dB per octave roll off with the -3dB point typically considered it's cutoff frequency. To determine the value of capacitor for a given frequency you will need to know the impedance of the speaker (any type including horn tweeters) and refer to a chart or get the formula... do a google search there are dozens of places to find this info.

Off the top of my head here is an example. For an 8 ohm speaker a 4 uF cap will give you a -3dB point of 5KHz, 2 uF will be 10KHz, 1 uF will be 20KHz.

A first order crossover has such a gentle slope that even the 1uF cap will allow a significant amount of acoustic energy be produced by a tweeter that only has a response to 20KHz.

In answer to the second half of your question, obviously all three values would be around 1 uF but I am confident you won't hear a difference between these three values... certainly not at those frequencies.

It is convenient to talk about these networks as blocking the lows or cutting off low frequencies, but in reality it isn't that simple. If you really want to study the matter you will discover that different order crossovers have different effects of the phase of the drivers, and will affect their polar plots, and will have differing amounts of driver interaction.

Widget

frank23
06-14-2005, 12:56 PM
it is of course more complex than simply adding a capacitor in series

but if you want to do it the simple way you have to consider 2 things:
- cross over at least 1 octave from the impedance peak caused by resonance
- match the sound level by adding a resistor deviding network between capacitor and driver

if this simple method is performed right, it can be quite effective, especially because your ears are a lot less sensitive at 15kHz than at 1.5kHz, so any errors are not so prominent

greetings, Frank

ngccglp
06-14-2005, 03:13 PM
Thanks guys.

My Altec A7 mid and bass drivers are all 8 ohms, but the tweeter is 16 ohms, can I still use the tweeter or must I really change the diaphragm to a 8 ohm?

Mr. Widget
06-14-2005, 03:31 PM
The name plate may say 16 ohms but it is quite possible that at the crossover region the driver isn't actually 16 ohms... in any case it's impedance relative to the other drivers is immaterial. It's impedance must be taken into account in regards to designing it's high pass filter. (Choosing a cap in this case.)

Widget

ngccglp
06-15-2005, 03:47 AM
Thanks Widget,

You are spot on, the value of the capacitor used by my friend is 1 uF.

Any idea what value of the capacitor I should use if the driver is 16 ohms. I've been hunting around, so far can only find 2405 that are 16 ohms.

Thanks.

spkrman57
06-15-2005, 04:00 AM
Try a .47 ufd cap.

ROn

Mr. Widget
06-15-2005, 09:49 AM
One of the frequently corrected JBL facts is that all 077s and 2405 have the same impedance and use the exact same diaphragm regardless of the rating on the foilcal. Actually as you will see from my plot they do vary, but it isn't due to the name on the back, it has to due with winding tolerances and the loading of the horn. In any event here is a plot of the impedance curve of four samples of JBL Slot tweeters. Two were 077 and two were 2405. As you can see they vary a bit. For your purposes I'd go under the assumption that they are 10 ohms. I think 1uF will be a fine starting point. There is no harm in messing around with other values. I wouldn't use a first order network on these for pro sound, but for home use, to misquote JBL you will experience discomfort before the tweeter does.

Widget

ngccglp
06-16-2005, 05:58 AM
Thanks guys.

I borrowed my friend's 8 ohm 2403 to try and with 1uF cap in series, the sound seems just about right to me.

Will the 16 ohm 2405 driver sound twice as loud as the 8 ohm driver? I intend to only connect 1 uF cap in series to the driver.

johnaec
06-16-2005, 06:04 AM
Will the 16 ohm 2405 driver sound twice as loud as the 8 ohm driver? I intend to only connect 1 uF cap in series to the driver.What Widget was trying to point out is that ALL 2405's ahould be considered 8 ohms, regardless of what they say - they're the same diaphragm.

John

Mr. Widget
06-16-2005, 09:48 AM
Well sort of... I was saying that in fact they should all be considered 10 ohms.

But yes, we have gone on and on about this, I personally have posted it too many times, but there are several vintage JBL products where the actual impedance was somewhere between 8 ohms and 16 ohms and the labels on them seemed to change with the times... i.e. when 16 ohms was popular they were rated as 16 ohms, and later when 8 ohms was more popular they changed the rating... only the rating... the devices were not changed.

Therefore the LE15A, LE85, 077, 2405, 075, 2402 and a few others are all the same whether it states 8 ohm or 16 ohm. I am not saying that the LE15A has the same impedance as the LE85, but rather all LE85s have the same impedance even though older ones say 16 ohms and newer ones say 8 ohms.

Clear as mud?

Widget

edgewound
06-16-2005, 10:49 AM
Another approach would be to measure the DC resistance of the voice coil to make sure it's in the same neighborhood as the nominal impedance printed on the label. 077, 076, 2403,2405, 075, 2402, 2404H-1 can all be fitted with either D8R075, D16R076 or D16R2405 diaphragms...all annular ring radiator types. Usually, a crossover network design program will ask for the DCR and Inductance of the voice coil, and also ask what type of filter you want to use...Butterworth, Bessel, Chebychev, Linkwitz-Riley....


Maybe that'll muck up the mud some more for you, maybe it will help:)

Good Luck

Edgewound

Zilch
06-16-2005, 02:07 PM
077, 076, 2403,2405, 075, 2402, 2404H-1 can all be fitted with either D8R075, D16R076 or D16R2405 diaphragms...all annular ring radiator types.With respect to mechanical fit and impedance, yes.

That is not to say they are the same in all other respects, tho, just so nobody is misled in that regard.

Edge: What's the difference between 2404H, 2404H-1, and 2404H-2?

ngccglp
06-16-2005, 03:44 PM
Thanks guys,

I'll be getting the 2405 16 ohms and will experiment with cap between 1 to 2 uF to determine the optimal point.

Don't think I can go back after hearing the A7 with the 2403:D . I think the hi freq harmonics produced by the 2403 is making the instruments sounds more real and 3-D.

ngccglp
06-17-2005, 05:42 PM
I finally mustered enough courage to download a version of crossover design software to work out the correct value of the cap to use for my 2405 16 ohms.

Surprisingly, it was quite easy to use. Just wanna be sure, could someone with similar software check my answer:

3 way first order:

Tweeter 16 ohm

Mid 8 ohm

Bass 8 ohm

LF 500 hz

HF 18000 hz

the value of the capacitor calculated is 0.55 uF.

Thanks.

speakerdave
06-17-2005, 06:23 PM
I gather you are planning to let your midhorn run on up and you just want to cut the tweeter in up high to add to the HF output of the midhorn. Your .55uf won't hurt anything, but I don't think the tweeter is going to be making very much sound. Why not try your software using the 10 ohm rating as has been suggested would be more accurate?

David

Zilch
06-17-2005, 06:28 PM
10 Ohms, not 16.

If it's a JBL 2405, it doesn't matter what the foilcal says.

We ain't just flappin' our digits here.... :p

Alex Lancaster
06-17-2005, 07:52 PM
:) ng: 18KHz???, what for?, use a 1uF cap, done it bunch of times.

ngccglp
06-18-2005, 01:31 AM
One more question: can I just tap the signal from the Altec 802 terminal or must I tap the signal from the crossover terminals? I think logically it should be the latter because the signal has not passed through the internal crossover yet.

Actually, I also did the calculation for 8 ohms and 10 ohms so that I can get a range of values to experiment.

The reason I am crossing at about 18 khz is because I am worried that there will be too much overlap between the 2405 and the Altec 802.

Seems like there's some consensus on crossing at a lower at about 15 khz. I'll try it out with some cheap cap before investing in good caps.

Thanks.

Alex Lancaster
06-18-2005, 06:39 AM
:) I would tap it at the CDriver terminals, and experiment with the polarity.

Datubie
06-18-2005, 07:08 PM
Do you know where "Koba" is? You can find lots of cheap caps & nick nacks there. They are located in Peoples Park Center (Same building as Larry Hifi), 3rd floor.

Better to tap from before the xover.



One more question: can I just tap the signal from the Altec 802 terminal or must I tap the signal from the crossover terminals? I think logically it should be the latter because the signal has not passed through the internal crossover yet.

Actually, I also did the calculation for 8 ohms and 10 ohms so that I can get a range of values to experiment.

The reason I am crossing at about 18 khz is because I am worried that there will be too much overlap between the 2405 and the Altec 802.

Seems like there's some consensus on crossing at a lower at about 15 khz. I'll try it out with some cheap cap before investing in good caps.

Thanks.

ngccglp
06-18-2005, 10:27 PM
Thanks all,

Datubie - wanted to call you, but thought you will be busy and all...

I've tried the 1 uF cap. Its sounds good. Think I will stick with this value.

Will try to get a longer length of cable to experiment tapping from the crossover terminals. Problem is need to find real thin cables in order to squeeze it into the hole.

Datubie
06-20-2005, 06:51 AM
Duty's done & I'm for now.:D


Thanks all,

Datubie - wanted to call you, but thought you will be busy and all...

I've tried the 1 uF cap. Its sounds good. Think I will stick with this value.

Will try to get a longer length of cable to experiment tapping from the crossover terminals. Problem is need to find real thin cables in order to squeeze it into the hole.

Rudy Kleimann
08-14-2005, 11:40 AM
If you're gonna try through the crossover, make it easy on yourself. Grab the output from the horn drivers' terminals. What's crossed over is crossed over. What's phase shifted (from the horn crossover) is just that. You'll be closer to in-phase by tapping it here, and you're so high in frequency relative to the horn crossover point that you aren't going to affect the horn's crossover any at all.

To determine your true crossover frequency with any given capacitor, just drive it directly from the amp at about 1 volt with a frquency generator source. hook the cap between the hot out of the amp and the hot in of the 2405 and the negative of the amp directly to the negative of the 2405. Hook up a volt meter across the two leads on the cap. While sweeping the frequency up, watch until the meter reads 0.5Volts. Now, just to be certain nothing funny is going on, check the voltage across the tweeter terminals and verify it reads the same voltage as it does across the capacitor. The frequency that these voltages are equal is the crossover point, or 6dB down point.

Personally, I would bring those tweeters in lower, since that horn doesn't make it up anywhere near 15KHz before its' output falls off to nothing. If you're shooting the juice to the system, you better make a higher-order crossover if you come in very low.

I'm using 2405's coming in at 7-8KHz, with JBL 2447H's on 2352 horns for mids. In this case, I am tri-amping through a Rane 24dB/Octave crossover (in-phase throughout the crossover region) with the internal CD Horn EQ modification on the mid x-over output to the 2447/2352's amp. This mid/hi setup sits atop JBL 4638 theatre cabinets (JBL 4508A double-15" 8 Cubic ft. 40Hz ported cabs, with 2-JBL 2035H 8-ohm woofers in them).
Sounds pretty good for a dang-ole' club live sound system... http://audioheritage.org/vbulletin/images/smilies/biggrin.gif

ngccglp
08-19-2005, 04:09 PM
Thanks for all the advice. Just to give an update on my experiments:

I tried the 2405 coming in at a range of values from 8k to about 18k. First impressions were that I liked the extra emphasis on the highs when crossed low at about 8k to 10k. But on extended listening (a few months) and experimentation, I noticed the low freq articulation was masked by the extra high freq, also the sound becomes a bit forward and hard when pushed loud, adjusting the attenuator did not help. After listening to the 2405 for awhile, I decided to unhook it just to see the difference. I was pleasantly surprised to hear a much more natural sounding A7, all the details are presented in a natural way with deep soundsatge, and the speakers sounded relax, which was the reason I bought them in the first place. This prompted me to cross the 2405 at higher freq, just to add the extra sparkle and extension to the 802, while maintaining the inherent character of the A7. Now I have settled on 0.82 uF which is 18k I think.

I learned an important lesson, that Balance in the full freq spectrum is very important, even adding a bit more highs can tilt the character and presentation of the speakers. It has been fun. :D

Datubie
08-19-2005, 10:35 PM
You should try out a band pass filter on the 802, leaving the 2405 as the sole source hf producer.

Hamilton
08-20-2005, 07:42 AM
I did this same thing with my 4430s, I wanted just a touch more sparkle on the high-end so I got a pair of 2404Hs. I ended up with .68uF caps coupled with .15mH chokes.

Akira
08-20-2005, 12:58 PM
timely thread as passive networks are a weak point in my background
i am also trying different caps on a 2405 crossed over to a LE5-2 mid. the original 1st order cross over point in my box is 7K5. i am trying to increase the slope with an additional cap at around 6K to eliminate the harsh metallic sound of the slot when driven hard around 3-4K.

my question: does adding a high pass filter to an existing network simply increase the slope an additional 6db per octave? in other words if my network produces a 3db down point at 7K5 @ 6db/octave, would a second cap in series increase the slope to 12db/octave.

Earl K
08-20-2005, 02:40 PM
my question: does adding a high pass filter to an existing network simply increase the slope an additional 6db per octave? in other words if my network produces a 3db down point at 7K5 @ 6db/octave, would a second cap in series increase the slope to 12db/octave.

NO !
- Wiring 2 caps end to end ( as in your given example ) just equates to creating a single cap of lessor value .
( Yes, this typically boogles the mind :D ) .
- Example : If your additional cap has the same value as your original cap ( for the 7500hz point ) / then the new crossover point is going to be around 15K ( still having a 6db/octave slope )
- You need a shunting coil ( an inductor ) of appropriate value ( wired across ) the line, after the series cap ) to obtain a 12 db per octave slope .



i am also trying different caps on a 2405 crossed over to a LE5-2 mid. the original 1st order cross over point in my box is 7K5. i am trying to increase the slope with an additional cap at around 6K to eliminate the harsh metallic sound of the slot when driven hard around 3-4K.

- It's probably best that you just copy the component values from other stock hipass filters ( with 12 or 18 db slopes ) .
:p

EDIT Here's a doctored 12 db per octave hipass meant for the 077 & 075 tweets . It has as its' stated point, a crossover point somewhere around 7K. This ought to be useful to you. This drawing was copied & cleaned up from the 3106 network schematic ( the lowpass section was eliminated ) . The original is posted in the JBL Network Schematics (http://www.jblproservice.com/navigation/Network%20Schematics.html) section .

Mr. Widget
08-20-2005, 04:03 PM
I just drew this up. These are your basic network topologies, there are other types as well. A typical schematic can look more complex because of added zobels (conjugates), notch filters, and padding.

Widget

Hamilton
08-20-2005, 04:55 PM
i am trying to increase the slope with an additional cap at around 6K to eliminate the harsh metallic sound of the slot when driven hard around 3-4K.
I experienced that too, until I started employing inductors. http://audioheritage.org/vbulletin/images/smilies/smile.gif

Thanks for the schematics, Mr. Widget, the light has come on understanding 3rd order. http://audioheritage.org/vbulletin/images/smilies/smile.gif

edgewound
08-20-2005, 06:42 PM
With respect to mechanical fit and impedance, yes.

That is not to say they are the same in all other respects, tho, just so nobody is misled in that regard.

Edge: What's the difference between 2404H, 2404H-1, and 2404H-2?

To my knowledge, the contents of my JBL Service lit, and the JBL Pro and Consumer websites...2404H-2 doesn't exist. The other two take D16R2405 as the default diaphragm assembly. It could be....but my memory is not too good today....the 2404H originally used D8R075. My old service lit is at my shop...I'm at home as I write this and can't reference. Maybe you could help me Zilch?

Zilch
08-20-2005, 07:34 PM
To the best of my knowledge, 2404H uses 2405 diaphragm and has the same HF extension as 2405H, but with the 100 degree biradial dispersion, of course, and a substantially lower crossover point.

2404H-1 uses the 2402 diaphragm and doesn't play as high, but is more rugged for Sound Reinforcement applications. It was used and Cabaret and subsequent SR systems. The spec sheets would imply it can cross over a little lower than the standard driver, as well: http://www.jblpro.com/pages/components/uhf_drvs.htm#2404H.

2404H-2, as you say, very likely doesn't exist, except I have 4 of them. :p

They also have 2402 diaphragms in them.

edgewound
08-20-2005, 08:02 PM
To the best of my knowledge, 2404H uses 2405 diaphragm and has the same HF extension as 2405H, but with the 100 degree biradial dispersion, of course, and a substantially lower crossover point.

2404H-1 uses the 2402 diaphragm and doesn't play as high, but is more rugged for Sound Reinforcement applications. It was used and Cabaret and subsequent SR systems. The spec sheets would imply it can cross over a little lower than the standard driver, as well: http://www.jblpro.com/pages/components/uhf_drvs.htm#2404H.

2404H-2, as you say, very likely doesn't exist, except I have 4 of them. :p

They also have 2402 diaphragms in them.

Interesting...hmmm...Is that from a JBL System? Or OEM for someone else? 2404H-2 exists on the parts order entry site for dealers/servicers, but not in the service lit for tranducer parts. Again....learn something everyday...thanks for the pic-proof.

Zilch
08-20-2005, 08:10 PM
Interesting...hmmm...Is that from a JBL System? Or OEM for someone else?An eBay purchase, the seller had a bunch of 'em at the time. No knowin' what they came out of.

It's reassuring to know they exist on a list somewhere. There's likely some different OEM spec about them; it'd be cool to know just what that is.

Until I find out otherwise, I'm tellin' everybody they have aquaplas-dusted beryllium diaphragms in 'em. ;)

edgewound
08-20-2005, 08:24 PM
What part of the World did they come from? Maybe an overrun of an OEM buy since he had a bunch of them....or...maybe....from Audio Composite Engineering, which used JBL drivers and then sold out to QSC who no longer has a relationship with Harman/JBL.....how's that for conjecture? Probably wrong, but was fun coming up with the theory:p

Looking at the lower right corner of your 2404H-2 pic...that mounting hole interior has an aluminum casting look to it....is the horn aluminum? 'cause the others, as you know, are plastic. If so...maybe that's the difference?

Zilch
08-20-2005, 08:30 PM
What part of the World did they come from?Ohio, of course. :p

edgewound
08-20-2005, 08:49 PM
I should've said this earlier, Zilch. Anytime there is a -1,-2,-3, etc., after an existing model, it means that it's a revised factory-progressive improvement in the driver. I do believe that the 2404H started life with a D8R075 diaphragm in keeping with the "H" 8 ohm designation. The 2404H-1 later went to the D16R2405 diaphragm that can go higher because the aluminum ring diaphragm is a little thinner and lighter....and is the current diaphragm called out for both models. As Wigdet's posts pointed out these fall somewhere between 8 & 16 ohms. Any other experts care to join the debate? Maybe shed more light?

Akira
08-22-2005, 09:54 AM
- Wiring 2 caps end to end ( as in your given example ) just equates to creating a single cap of lessor value .
( Yes, this typically boogles the mind :D ) .
- Example : If your additional cap has the same value as your original cap ( for the 7500hz point ) / then the new crossover point is going to be around 15K ( still having a 6db/octave slope )
- You need a shunting coil ( an inductor ) of appropriate value ( wired across ) the line, after the series cap ) to obtain a 12 db per octave slope .

EDIT Here's a doctored 12 db per octave hipass meant for the 077 & 075 tweets . It has as its' stated point, a crossover point somewhere around 7K. This ought to be useful to you. This drawing was copied & cleaned up from the 3106 network schematic ( the lowpass section was eliminated ) . The original is posted in the JBL Network Schematics (http://www.jblproservice.com/navigation/Network%20Schematics.html) section .

just to get this right, does the inductor come after the newly added 2nd cap which is in series after the original filter. from the diagram it looks like the inductor is after a single cap (1.5mF) for a 12db/octave slope. if i simply added the inductor after the original 7K5 ist order cross over would that give me the 12db slope i'm looking for?

Earl K
08-22-2005, 11:08 AM
Akira,

Click Here ! (http://ccs.exl.info/calc_cr.html#second) to go to an online calulator that is helpful for designing simple passive crossovers .

- There are pictures present which also show the layout for each sort of network ( like Widget has shown above ).

- Enter your desired crossover values / along with your drivers specified impedances.

- The necessary values for L (inductor) & C (capacitor) are calculated for you. My IE5 browser creates the "result windows" as boxes that are just too narrow for all the resulting numbers to fit into / so , you'll need to get your cursor into them to find the first relevant numbers .


just to get this right, does the inductor come after the newly added 2nd cap which is in series after the original filter.(?)

- See the following ,,,,,

Creating a 12 db from your existing 6 db filter

- In a 12 db hipass, the conjugate ( paralleled ) inductor must always come after the series capacitor . So yes . But ,,,,

- Build a completely new CL filter from scratch. Retire your original capacitor. It's value is likely not salvagable or useful ( unless you know & understand the math ) . Ie; don't wire two caps "end to end" since you don't know what their effective capacitance value becomes .

Are you adding this 077/2405 to an existing L100 network ?

If so,,,,

- Add a 20 ohm conjugate ( parallel ) resistor just before the 2405 ( just after the 8 ohm variable Lpad / you can even strap this resistor right across the 077s two terminals ). This will also help normalize ( stabilize ) the impedance of the Lpad/2405 combo, into something quite close to 8 ohms (then the mentioned online calculator might actually be relevant ) .

- I also think you need some added attenuation for that 2405 to ease the job of level matching. Give your existing variable Lpad a break by wiring in an additional "fixed" 6 to 10 db pad just before the existing variable pad. This fixed pad will burn off some excess energy allowing the variable pad to rotate somewhere within the middle of its' range .

- You are going to have to play around with this tweeters' polarity to find the best acoustic summation in the crossover area .

:p

Akira
08-22-2005, 12:26 PM
Are you adding this 2405 to an existing L100 network ?

If so,,,,
- Add a 20 ohm conjugate ( parallel ) resistor just before the 2405 ( just after the 8 ohm variable Lpad / you can even strap this cap , right across the 077s two terminals ). This will also help normalize ( stabilize ) the impedance of the Lpad/2405 combo, into something quite close to 8 ohms .
- I also think you need some added attenuation on your 2405 to ease the job of level matching. Give your existing variable Lpad a break by wiring in an additional "fixed" 6 or 10 db pad just before the variable pad. This fixed pad will burn off some excess energy allowing the variable pad to rotate somewhere within the middle of its' range .

:p
WOW! not much gets past members in this forum. you are right, this is an early L100. i purposely failed to mention that because i feared ridicule from other members as a result of all of the derogatory L100 comments. it just so happens that the slot sounds great in the box, but there is the slope problem i'm working on. the original L100 had a 9db attenuation pad from the zero reference standard. -9db sounds just about right, but it leaves me with no room to play. i am also wondering if the extra attenuation i'm adding at the natural cross over has any negative effects at the output stage; i can't hear anything bad.
p.s. i'm still confused on one thing. in the above example, would adding the inductor only, to the existing 7K5 crossover create a12db slope, or in the case that i suggested, two summed caps equalling 15K create a 12db slope at half that frequency? (7K5)
p.p.s. your URL reference calculator is great! a must have for members like me who are weak in this area. much appreciated...

Lancer
08-22-2005, 01:02 PM
i feared ridicule from other members as a result of all of the derogatory L100 commentsOMG! Fear nothing! Crush your enemies, drive them before you and hear the lamentations of their women!

Earl K
08-23-2005, 10:04 AM
Hi


p.s. i'm still confused on one thing. in the above example, would adding the inductor only, to the existing 7K5 crossover create a12db slope, or in the case that i suggested, two summed caps equalling 15K create a 12db slope at half that frequency? (7K5)

- I'm really not sure what you are getting at here .

- Have you tried out the referenced online calculator ?

- If so, did you actually find an instance where your existing (3uf) capacitor could be retained ? ( & all the while giving a useful crossover point in the 6K to 10K region )

:p

Zilch
08-23-2005, 12:44 PM
I purposely failed to mention that because i feared ridicule from other members as a result of all of the derogatory L100 comments.L100's suck.

We say that with authority, because we all have 'em!

[Many with multiple pairs.... :p ]

Mr. Widget
08-23-2005, 12:59 PM
L100's suck.

We say that with authority, because we all have 'em!

[Many with multiple pairs.... :p ]

Maybe we should take your Q+D concept to heart and consider some mods for them. I like the basic design, but I can think of several "minor" changes that would radically improve them....:hmm:


Widget

Zilch
08-23-2005, 01:05 PM
I can think of several "minor" changes that would radically improve them....:hmm:That's what Akira is apparently trying to do.

We need an organized approach and a new thread, is what.... :p


Maybe we should take your Q+D concept to heart and consider some mods for them.TWO-way?

[I can dig it.... :bouncy: ]

Mr. Widget
08-23-2005, 01:07 PM
We need an organized approach and a new thread, is what.... :p
Yeah... let's talk again in the Spring when you are finished with the "Two-way" thread...;)


TWO-way?

NO! :banghead: That would not be the L-100... besides, JBL did that already. It was called the L-88.

Widget

Akira
08-24-2005, 08:39 AM
L100's suck

Maybe we should take your Q+D concept to heart and consider some mods for them. I like the basic design, but I can think of several "minor" changes that would radically improve them....:hmm:
Widget
a hippo in a dress is still a hippo, and a modified L100 is still an L100. i have no illusions as to the limitations of this infamous speaker as i have owned over 52 JBL enclosures each with multiple drivers as well as other non JBL professional studio monitors and designer sound systems such as Turbosound...it's what i do for a living. i'm doing this for fun and because i have several spare parts and peripheral electronics.
i am currently working on six L100 modifications never seen before in this forum. i will have a detailed history, mod pics and test results in a few weeks...then you call all throw flames at me!
:thnkfast:
or rocks!!
p.s. at least i'll have a prettier hippo!!! :D

edgewound
08-24-2005, 09:18 AM
I'm going to come to the defense of the good 'ol L100. It pretty much gave JBL to the masses and went on to become probably the most widely used studio monitor in existence...the 4311...and copied...sort of...by many. Sure, the early crossovers are pretty rudimentary, but the drivers are very competent. Update the crossover with symetrical filters with good components and you still have a very competent speaker. So...I don't thin' the L100 sucks...and neither do lots of other people that have and love them.