I use a J2 along with an SIT 1 to drive the two sections of a Klipsch K401 based MEH horn based upon the idea of the very prickly Chris A frm the Klipsch forum.
It is a very good sounding speaker. Using the CELESTION Axi Periodic compression driver which I find to be exceptionally fine. Much better than the JBL Truextent combo I was using.
Sorry for all of that.
I am intrigued by the pure single ended aspect of the J8 - thinking it would blend better with the SIT 1.
Since one channel of a J2 has two of the precious SEMISOUTH devices these could be used to make two channels of of an F8. One part of me likes the idea of using four amplifiers to drive each of the woofers in the speaker instead of having them wired in series.
I have already converted my amps into mono blocks so the conversion would be fairly simple - two two channel amplifiers instead of a mono ampllifier.
The question is: is there any chance something like this could be done? Or far more precisely, any chance Mr. Pass would sell a PCB to those who are J2 owners? Maybe an exchange program would be better still to keep errant boards off of the market. Send in one J2 channel's PCB and get two F8 pcbs.
Would our great benefactor consider such a project in the New YEar?
It is a very good sounding speaker. Using the CELESTION Axi Periodic compression driver which I find to be exceptionally fine. Much better than the JBL Truextent combo I was using.
Sorry for all of that.
I am intrigued by the pure single ended aspect of the J8 - thinking it would blend better with the SIT 1.
Since one channel of a J2 has two of the precious SEMISOUTH devices these could be used to make two channels of of an F8. One part of me likes the idea of using four amplifiers to drive each of the woofers in the speaker instead of having them wired in series.
I have already converted my amps into mono blocks so the conversion would be fairly simple - two two channel amplifiers instead of a mono ampllifier.
The question is: is there any chance something like this could be done? Or far more precisely, any chance Mr. Pass would sell a PCB to those who are J2 owners? Maybe an exchange program would be better still to keep errant boards off of the market. Send in one J2 channel's PCB and get two F8 pcbs.
Would our great benefactor consider such a project in the New YEar?
easily reconfigurable to use same PSU, but amount of capacitance is under question
I can see it doable only in Papa's own arrangement
personally, in case of having J2 already in hands, wouldn't bother with conversion to F8
of course that difference between J2 and F8 is absolutely justifying F8 as completely new product, on several important levels but - without actual listening tests of F8 itself, one can't be sure of amount and nature of sound differences and adequacy of same in one's system
I can see it doable only in Papa's own arrangement
personally, in case of having J2 already in hands, wouldn't bother with conversion to F8
of course that difference between J2 and F8 is absolutely justifying F8 as completely new product, on several important levels but - without actual listening tests of F8 itself, one can't be sure of amount and nature of sound differences and adequacy of same in one's system
Alternatively send the J2 to Pass Labs and tell them you want your J2 converted to 2 x F8 amps.
If you do it yourself, the resale value will be terrible. If you get Pass Labs to do it you will hold onto the resale value of the amps.
If you do it yourself, the resale value will be terrible. If you get Pass Labs to do it you will hold onto the resale value of the amps.
My amps are already unsellable - they have been converted into mono blocks.
I have no intention of ever selling them.
Reconfiguring power supply would be simplicity.
Only thing I would wonder is if the LUNDAHL chokes in the power supply would have enough margin to use in the F8 circuit - not that it is important to retain them
But of course, without Mr. Pass offering this in some form or another it will not happen.
Would love to have 25 watts into each woofer ...
I have no intention of ever selling them.
Reconfiguring power supply would be simplicity.
Only thing I would wonder is if the LUNDAHL chokes in the power supply would have enough margin to use in the F8 circuit - not that it is important to retain them
But of course, without Mr. Pass offering this in some form or another it will not happen.
Would love to have 25 watts into each woofer ...
You will appreciate that there are no plans to make the F8 circuit public at this time.
Last time I did that was with the F6, and it killed sales overseas.
Last time I did that was with the F6, and it killed sales overseas.
I am not asking for you to give up the circuit by any means.
I was hoping you might offer the completed boards for sale in an exchange program.
I send you J2 boards and you send back completed F8 boards at a price that would make it worth your while.
I was hoping you might offer the completed boards for sale in an exchange program.
I send you J2 boards and you send back completed F8 boards at a price that would make it worth your while.
It finally occurred to me that driving each woofer separately means I am dealing with a nominal 4 ohms load which would get me nowhere with power.
One does wonder if there might be a simpler F8 style first stage circuit for the J2? One cannot help but wonder what the simpler circuit would sound like. Always wanting more. The woofers driven by the J2 are only going from 50 hz to 500 hz at full level. There is a high pass filter. Whether a different first stage would make any difference is maybe doubtful?
At approx 500 Hz there is a steep drop as one would expect with an MEH but there is a great big spike at approx 1250 Hz that only be quelled with dsp. The whole speaker requires dsp to work well. I am using the xilica Sp2040 one for each channel and I find the things to sound just fine. No question suing the purist approach does not sound anywhere near as good so whatever faults the xilica's have, and I am dure there a quite a few - are negated by what it can for the frequency response.
With the Rythmik subwoofers in the mix I get less than 250 degrees of phase change from top to bottom. Without the subs is like 120 degrees - but there is no question the thing sounds much better without asking the woofers to make low bass. Measured at four feet from the front of the cabinet which seems to correlate, sonically, with what i hear at my chair. Not that there is any resemblance in the measured frequency response at the chair! Measuring closer in results in even smoother measurements but the sound is not very good. Rooms are mysterious things ...
Sorry for not thinking this through more thoroughly. And for going on about a loudspeaker.
One does wonder if there might be a simpler F8 style first stage circuit for the J2? One cannot help but wonder what the simpler circuit would sound like. Always wanting more. The woofers driven by the J2 are only going from 50 hz to 500 hz at full level. There is a high pass filter. Whether a different first stage would make any difference is maybe doubtful?
At approx 500 Hz there is a steep drop as one would expect with an MEH but there is a great big spike at approx 1250 Hz that only be quelled with dsp. The whole speaker requires dsp to work well. I am using the xilica Sp2040 one for each channel and I find the things to sound just fine. No question suing the purist approach does not sound anywhere near as good so whatever faults the xilica's have, and I am dure there a quite a few - are negated by what it can for the frequency response.
With the Rythmik subwoofers in the mix I get less than 250 degrees of phase change from top to bottom. Without the subs is like 120 degrees - but there is no question the thing sounds much better without asking the woofers to make low bass. Measured at four feet from the front of the cabinet which seems to correlate, sonically, with what i hear at my chair. Not that there is any resemblance in the measured frequency response at the chair! Measuring closer in results in even smoother measurements but the sound is not very good. Rooms are mysterious things ...
Sorry for not thinking this through more thoroughly. And for going on about a loudspeaker.
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