yairf
Trade: Teddy Pardo Audio
Hi all
I have finally found the time to complete the installation of the TPR boards within my 32.5, and bring the 32/140 project to the final scene.
As for the TRPs - yes I know, the ALWSRs are WAYYYYY better, however the TPRs are just so cheap, so small and easy to build that I just couldn't say no...
Anyway, putting all the pieces together, I have finally given the beast a listen and the sound is just jaw-dropping - so powerful, dynamic, so authoritative!
I just couldn't belive this is an old pair of 32/140 playing - it could drive my B&W M801 ("The Gentle Giants") as if they were cute little monitors!
I am certainly not done with modding these old chaps, there is a remote-control board + pot waiting to go into the 32.5.
However, this is a very important milestone for me - after about two months of after-hours work, these two just came alive, BIG TIME, and they sound SOOOO GOOOD, only proving that the hard work paid itself.
Before I go on with descriptions, I wish to thank this TREMENDOUS forum for the inspiration and information.
A huge word of thanks goes to LesW - I just couldn't (and probably wouldn't) make it without you.
For those who are interested, the current configuration is:
Hi-Cap
- Kendeil K1s installed, output voltages increased to 29v.
- each circuit has its own ground signal going towards the preamp star-earth (common ground broken into two, per Mr Tibbs mod) - the two of them routed via a normal SNAIC cable, replacing the audio lines within it (this way the shield is only doing its job, and NOT carrying the ground signal).
Preamp
- Loads of board mods, most of them are based on LesW's advice, balance pot bypassed, buffer boards remain but their bandwidth increased.
- one TPR board physically and electrically adhered to each one of the four boards: two buffers, two gains. The (short) TPR links are essentially replacing the 27R/47uF in each board.
- Cardas wiring throughout, shielded cables for Phono + Aux inputs, as well as signal output, wired directly to the motherboard pins holding the gain boards, terminated with RCA plugs (look mom! no DINs!! )
Power amp
- loads of mods to the boards, removal of protection circuit, change of input filter per NCC-200 values.
- Local feedback resistors added to the long-tailed-pair input stage, per NCC-200.
- Cardas wiring throughout, including a new star-earth.
- Binding posts, DIN plug & mic cables - trashed, replaced with RCAs, binding posts and shielded cables, all sourced from Cardas. Signal input wired going directly from RCA sockets to the NAPA boards signal input.
- Main caps replaced with BC-58, 10,000uF/40V (low ESR) - the size of which fits exactly within the space available in the PS boards. All the four are bypassed with 0.1uF Wima caps.
Yair
I have finally found the time to complete the installation of the TPR boards within my 32.5, and bring the 32/140 project to the final scene.
As for the TRPs - yes I know, the ALWSRs are WAYYYYY better, however the TPRs are just so cheap, so small and easy to build that I just couldn't say no...
Anyway, putting all the pieces together, I have finally given the beast a listen and the sound is just jaw-dropping - so powerful, dynamic, so authoritative!
I just couldn't belive this is an old pair of 32/140 playing - it could drive my B&W M801 ("The Gentle Giants") as if they were cute little monitors!
I am certainly not done with modding these old chaps, there is a remote-control board + pot waiting to go into the 32.5.
However, this is a very important milestone for me - after about two months of after-hours work, these two just came alive, BIG TIME, and they sound SOOOO GOOOD, only proving that the hard work paid itself.
Before I go on with descriptions, I wish to thank this TREMENDOUS forum for the inspiration and information.
A huge word of thanks goes to LesW - I just couldn't (and probably wouldn't) make it without you.
For those who are interested, the current configuration is:
Hi-Cap
- Kendeil K1s installed, output voltages increased to 29v.
- each circuit has its own ground signal going towards the preamp star-earth (common ground broken into two, per Mr Tibbs mod) - the two of them routed via a normal SNAIC cable, replacing the audio lines within it (this way the shield is only doing its job, and NOT carrying the ground signal).
Preamp
- Loads of board mods, most of them are based on LesW's advice, balance pot bypassed, buffer boards remain but their bandwidth increased.
- one TPR board physically and electrically adhered to each one of the four boards: two buffers, two gains. The (short) TPR links are essentially replacing the 27R/47uF in each board.
- Cardas wiring throughout, shielded cables for Phono + Aux inputs, as well as signal output, wired directly to the motherboard pins holding the gain boards, terminated with RCA plugs (look mom! no DINs!!
)Power amp
- loads of mods to the boards, removal of protection circuit, change of input filter per NCC-200 values.
- Local feedback resistors added to the long-tailed-pair input stage, per NCC-200.
- Cardas wiring throughout, including a new star-earth.
- Binding posts, DIN plug & mic cables - trashed, replaced with RCAs, binding posts and shielded cables, all sourced from Cardas. Signal input wired going directly from RCA sockets to the NAPA boards signal input.
- Main caps replaced with BC-58, 10,000uF/40V (low ESR) - the size of which fits exactly within the space available in the PS boards. All the four are bypassed with 0.1uF Wima caps.
Yair
