2435?

[DavidF]

- I do love that library .
- Thanks for taking the time and making the effort to post the scans .

I will second that. Your time is appreciated.

DavidF

[Thom]

It is with great trepidation that I ask this. Actually that's overstated but figuring that part of the country seems to be low on fluoxetine I'm glad this isn't face to face for almost certainly there is someware I should have looked and am a retrograde for not having done so but: Is there a horn,available for reasonable money, that shows the 2435 to good light? Also, is the taper of a 2 inch horn important when selecting a 1 1/2 to 2 adaptor? I've never read that it is but for some reason it seams like it might be. And, is bolting a 1 1/2 driver driver directly to a 2 inch horn a close to unforgiveable sin? I don't totally understand it but I believe that it is. When one looks inside the driver adapter of a multicellular horn (altec) there is an area that is less than non-abrupt (couldn't think of just the right word) I guess I'm saying that not all the transitions are as gentle as one might think they would have to be. I would sure like to have less questions to ask, however.

[Zilch]

Is there a horn,available for reasonable money, that shows the 2435 to good light?

My best results with the pro horns are with 2352. 2435 plays well on any of the JBL PT Waveguides, also, but they are HF devices and 1 kHz is about the lower limit.

I've also used some DDS horns down to 800 Hz successfully. One of them mounts vertically in Project Array configuration:

http://audioheritage.org/vbulletin/s...312&#post70312

I've tried just about every 1.5" Pro horn JBL makes, and am just now venturing into the heretofore unavailable Harman Consumer horns....

[4313B]

Any news with the ferrofluid question?
Thanks

They both use ferrofluid.

[Robh3606]

Hello Giskard

Thanks for the info I quess I will leave the drivers "wet" then.

Rob

[Zilch]

Full biased version of "Key" filter constructed using PE stock parts, top.

Performance of various PT Waveguides using 435Be JBL Pro equivalent 2435HPL, next, and 435Al equivalent 2431H, third. High pass is 800 Hz JBL 3110.

Best of lot, at least with respect to flatness of frequency response, is 2431H on PT-H1010. Compare to H9800, fourth.

Single-malt libation "OBAN" provided courtesy of forum member Macaroonie, bottom, with PT-H1010....

[John W]

Zilch,
Thanks for posting these plots.
I'm having a little problem matching your filter to the schematic, though.
Are both of the smaller caps 1uf? What did you come up with to get to 10.7 ohms?
Any ideas how different the filter would be with 10.5 ohms for the first resistor and 1.5mH on the last inductor?

[Zilch]

Hi, John.

I've been playing 2435HPL on PT-H1010 with this filter for two days, now. Smooth as that single-malt.

It's two 1.0 uF. I originally misread it as 0.6 uF on a printout, so that's 1.0 and 1.5 uF in the pic, i.e., wrong.

For 1.6 mH I used 2.0 mH, 20 ga, and unwound 32 turns.

L2 is 18 ga.

L1 is 20 ga.

Inductors are all Jantzen.

My bias resistors are 2.2M in the pic, as I ran out of 1.5M.

[Or misplaced 'em in the wrong bin, maybe.... ]

[Zilch]

Any ideas how different the filter would be with 10.5 ohms for the first resistor and 1.5mH on the last inductor?

10.5 Ohms will alter the attenuation slightly.

1.5 mH will narrow the notch at 1.8 kHz a bit, and deepen it.

When Giskard posts something to try, we can bank on it being precise.

So, I stick with the program, at least 'til I understand it.

http://audioheritage.org/vbulletin/s...4&postcount=21

[John W]

Thanks Zilch,
I see now that your resistor values are also taking into account the DCR of the inductors, which makes sense.
I agree it is best to just stick with the exact values, all else being equal. Is this filter meant specifically for the h9800?

[Zilch]

Thanks Zilch,
I see now that your resistor values are also taking into account the DCR of the inductors, which makes sense.

Yes, that's how I interpreted the circuit as Giskard posted it, since it was presented in proper format for Spice simulation, which would include the DCRs. Not specified was that of L2; I used my best guess for it, based upon prior experience. I've provided the DCRs of the inductors I used as the bottom entry in the schematic legends for each. If any of this is wrong, I expect I'll be "corrected" shortly.

I agree it is best to just stick with the exact values, all else being equal. Is this filter meant specifically for the h9800?

It's for some custom horns presently on order, but the circuit might be adjusted for use with 2435HPL or 2431H on other horns/waveguides. Understand that it's a compensation filter only; you have to add either active or passive highpass. I'm presently running it on 3110 until I can get an active biamp setup playing with it here....

[4313B]

Is this filter meant specifically for the h9800?

No, G.T. did it for his personal home system. Several forum members have expressed interest in building something similar. As has been stated elsewhere, the 045Be has been turned off and this latest circuit employed. The end result is a smoother overall response from the 435Be. Recently, G.T. was able to get three pairs of 476Be's for his personal use and they will replace the 435Be's.

[Zilch]

Thanks.
Back to Mr. Timbers notch filter, which I've been trying to figure out.
I can see the CLR filter to flatten out impedence peaks, and some attenuation. What else is it designed to do? Would most of it bennefit a passive crossover?

Parsed:

[Jakob]

I read somewhere that G.T in his earlier setup (when still using the tweeters) used a 24dB LP and 6 dB HP at somewhere from 650 to 750 Hz (1200FE to 435Be). Does anybody know if he changed anything of that when he began using the compensation circuit and lost the tweeter?

Thanks for any info!