I am using SIT1's to drive JBL2441's with TRUEXTENT diaphragms.
They are used above 500 hz. For a crossover I have 20uF of capacitance in series with the driver.
The 10000 uF of the internal caps and the 20 uF at the driver result in a value just under 20 uF which makes me think why not just place my crossover caps within the amp dispensing with the electrolytics and the CLARITY cap that is bypassing them.
I am not the least bit concerned about harming the value of my amps since I have no intention of ever selling them and have made mods that would preclude an easy sale. The amp will always be used as a 500 hz high pass amplifier.
I have replaced the 4.7 uF input cap with a 0.47 uF VCap which made a worthwhile improvement along with changes to the input and output wiring - better wire using the "select" XLR as the input using only two of the pins, obviously, and Ric Schultz's brilliant idea of bringing the output wires through (drilled) holes in the casing to have both these and the speaker wire clamped by the existing binding posts.
I would greatly appreciate any warnings, other than monetary value ones, as to whether this is an "OK" thing to do. Makes perfect sense to me but then that is why I asking for comments!
Thanks.
They are used above 500 hz. For a crossover I have 20uF of capacitance in series with the driver.
The 10000 uF of the internal caps and the 20 uF at the driver result in a value just under 20 uF which makes me think why not just place my crossover caps within the amp dispensing with the electrolytics and the CLARITY cap that is bypassing them.
I am not the least bit concerned about harming the value of my amps since I have no intention of ever selling them and have made mods that would preclude an easy sale. The amp will always be used as a 500 hz high pass amplifier.
I have replaced the 4.7 uF input cap with a 0.47 uF VCap which made a worthwhile improvement along with changes to the input and output wiring - better wire using the "select" XLR as the input using only two of the pins, obviously, and Ric Schultz's brilliant idea of bringing the output wires through (drilled) holes in the casing to have both these and the speaker wire clamped by the existing binding posts.
I would greatly appreciate any warnings, other than monetary value ones, as to whether this is an "OK" thing to do. Makes perfect sense to me but then that is why I asking for comments!
Thanks.
two ways of doing that :
-desolder original output caps , replace them with your 20uF cap , leaving output bleeder resistor as is
-desolder just present output wire (isolate loose end) , solder 20uF to SIT drain node (internal output node , pre- output caps) , solder new output wire from it , put new bleeder - 470R/3W across output posts
if you need some sketch , just say
-desolder original output caps , replace them with your 20uF cap , leaving output bleeder resistor as is
-desolder just present output wire (isolate loose end) , solder 20uF to SIT drain node (internal output node , pre- output caps) , solder new output wire from it , put new bleeder - 470R/3W across output posts
if you need some sketch , just say
That sounds like going a little extra
So of course, I like it.
At the moment I am simply replacing the caps just to hear what that does.
I would appreciate a drawing for the COMPLETE (zen) mod.
Hope the rains have not troubled you. Thought of you when I heard those reports.
Thanks and take care,
two ways of doing that :
-desolder original output caps , replace them with your 20uF cap , leaving output bleeder resistor as is
-desolder just present output wire (isolate loose end) , solder 20uF to SIT drain node (internal output node , pre- output caps) , solder new output wire from it , put new bleeder - 470R/3W across output posts
if you need some sketch , just say
So of course, I like it.
At the moment I am simply replacing the caps just to hear what that does.
I would appreciate a drawing for the COMPLETE (zen) mod.
Hope the rains have not troubled you. Thought of you when I heard those reports.
Thanks and take care,
tnx for asking ...... my pants are still dry , but that's not helping for those we saw in tv reports ; and water is still there , and amount of misery and pain will be visible only when water is gone .....
now to sketch - regarding physical layout- assume that OUT+ and OUT- are actual speaker posts ; rest is self explanatory
in second case , 20u and *R are wired with some extending wires
now to sketch - regarding physical layout- assume that OUT+ and OUT- are actual speaker posts ; rest is self explanatory
in second case , 20u and *R are wired with some extending wires
Attachments
First impression
Converted one amplifier last night.
I usually will try one channel at a time to make sure all works as expected. In addition, it is interesting to hear before and after together. I have found that the "side" which draws the least attention to itself is the lower distortion one.
The converted amplifier has much less hash/grit intermingled with the sounds we want to hear.
I am using a pair of very large Russian oil/paper caps. They had previously been used at the driver and were the best I had heard at that position. Needless to say I have not compared them to DUELUND's though I wish I could if only I hd a money tree in the backyard.
I completely removed the original caps since that was easy to do. Tonight I will try the the "direct connection" method. I like the idea of getting the signal off of the PCB as soon as possible.
Maybe the electricity was in a good mood last night - could it be that one channel's improvement could make THAT much difference? - maybe I was in the self-satisfied sureness of one's latest modification mode but I heard the best sound quality last night I have ever heard in my house. Can't wait to hear what happens with amp #2 and hope it was not all my imagination. Or the rye whiskey ...
THANKS very much for your guidance and knowledge.
Converted one amplifier last night.
I usually will try one channel at a time to make sure all works as expected. In addition, it is interesting to hear before and after together. I have found that the "side" which draws the least attention to itself is the lower distortion one.
The converted amplifier has much less hash/grit intermingled with the sounds we want to hear.
I am using a pair of very large Russian oil/paper caps. They had previously been used at the driver and were the best I had heard at that position. Needless to say I have not compared them to DUELUND's though I wish I could if only I hd a money tree in the backyard.
I completely removed the original caps since that was easy to do. Tonight I will try the the "direct connection" method. I like the idea of getting the signal off of the PCB as soon as possible.
Maybe the electricity was in a good mood last night - could it be that one channel's improvement could make THAT much difference? - maybe I was in the self-satisfied sureness of one's latest modification mode but I heard the best sound quality last night I have ever heard in my house. Can't wait to hear what happens with amp #2 and hope it was not all my imagination. Or the rye whiskey ...
THANKS very much for your guidance and knowledge.
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Russian PIO ....... or any other - put nice polycarbonate one across
I like 1uF Philips ones , but they're damn scarce
Duelunds ....... I'm not loosing my sleep because of them ; whenever I need proper big cap , there is either Russian PIO or, even better , Italian ICAR motor-run , but always polycarbonat (MKC in this neck of wood) in parallel
edit - you owe us some porn ...... even if I already know that you're better with brain and solder , then with lens 😉
I like 1uF Philips ones , but they're damn scarce
Duelunds ....... I'm not loosing my sleep because of them ; whenever I need proper big cap , there is either Russian PIO or, even better , Italian ICAR motor-run , but always polycarbonat (MKC in this neck of wood) in parallel
edit - you owe us some porn ...... even if I already know that you're better with brain and solder , then with lens 😉
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I guess this is as good a time as any
Not that I think of myself as a purveyor of porn.
More like industrial espionage or in my case domestic espionage?
These Russian caps are quite large for their capacity.
I have to say I am not big on the bypassing - maybe because of the FOSTEX T500's, as I have them configured, rising with frequency? I tend to think bypassing works better with direct radiators which need the sparkle?
Polycarbonates? I thought those were discredited - of course, all discredited components tend to be rediscovered (rehabilitated?). Just waiting to read somewhere that it has been decided that the second generation CROWN DC-300 has the most beautiful midrange of any amplifier ever made.
Don't think I have ever seen the Italian caps for sale over here. My sub-500 horn is using a B&C 12 inches driver that is quite fine; another Italian firm doing a great job.
Not that I think of myself as a purveyor of porn.
More like industrial espionage or in my case domestic espionage?
These Russian caps are quite large for their capacity.
I have to say I am not big on the bypassing - maybe because of the FOSTEX T500's, as I have them configured, rising with frequency? I tend to think bypassing works better with direct radiators which need the sparkle?
Polycarbonates? I thought those were discredited - of course, all discredited components tend to be rediscovered (rehabilitated?). Just waiting to read somewhere that it has been decided that the second generation CROWN DC-300 has the most beautiful midrange of any amplifier ever made.
Don't think I have ever seen the Italian caps for sale over here. My sub-500 horn is using a B&C 12 inches driver that is quite fine; another Italian firm doing a great job.
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