If you're reading this, you probably know what these amps are. I have the version with the tube cage and the IEC socket/removable power cord. I've made the following modifications/upgrades to these amps:
* Auricap coupling caps
* Panasonic TSHA/TSHB power supply caps
* Upgraded cathode bypass caps and added mylar bypass caps
* Upgraded RCA connector
* Replaced most resistors
* Reverse Recovery Spike Filter (RRSF) (aka "HV Snubber", design borrowed from discussions on the Bottlehead forum)
* Replaced rectifier diodes with UF4007
* Changed routing for heater grounds to keep them further away from signal grounds
* Teflon tape on tubes to damp microphonics
The following "under the hood" image shows the upgrades. The large yellow caps are the Auricaps. The black electrolytics are the Panasonic PS caps. The two large resistors and ceramic caps near the top are the RRSF, and the small yellow caps are the mylar bypasses on the cathode bias caps:
The teflon tape on the tubes:
A shot with the tube cage on:
And finally, the rear panel showing the IEC socket, speaker connectors and the RCA connector I added:
I bought the amps new from a dealer, and they've been in a non-smoking pet-free environment the whole time. They sound great in stock form, and the upgrades add a little more to their performance. These were my introduction to tube amps, and the only reason I'm selling them is because I was inspired to try building my own.
Price is $250 + shipping o.b.o. PayPal is preferred, money orders and personal checks are accepted. I've shipped lots of audio gear including turntables, so rest assured that these will be packed carefully.
Please respond to this thread or email me if interested.
Thanks for looking,
Saurav
* Auricap coupling caps
* Panasonic TSHA/TSHB power supply caps
* Upgraded cathode bypass caps and added mylar bypass caps
* Upgraded RCA connector
* Replaced most resistors
* Reverse Recovery Spike Filter (RRSF) (aka "HV Snubber", design borrowed from discussions on the Bottlehead forum)
* Replaced rectifier diodes with UF4007
* Changed routing for heater grounds to keep them further away from signal grounds
* Teflon tape on tubes to damp microphonics
The following "under the hood" image shows the upgrades. The large yellow caps are the Auricaps. The black electrolytics are the Panasonic PS caps. The two large resistors and ceramic caps near the top are the RRSF, and the small yellow caps are the mylar bypasses on the cathode bias caps:
An externally hosted image should be here but it was not working when we last tested it.
The teflon tape on the tubes:
An externally hosted image should be here but it was not working when we last tested it.
A shot with the tube cage on:
An externally hosted image should be here but it was not working when we last tested it.
And finally, the rear panel showing the IEC socket, speaker connectors and the RCA connector I added:
An externally hosted image should be here but it was not working when we last tested it.
I bought the amps new from a dealer, and they've been in a non-smoking pet-free environment the whole time. They sound great in stock form, and the upgrades add a little more to their performance. These were my introduction to tube amps, and the only reason I'm selling them is because I was inspired to try building my own.
Price is $250 + shipping o.b.o. PayPal is preferred, money orders and personal checks are accepted. I've shipped lots of audio gear including turntables, so rest assured that these will be packed carefully.
Please respond to this thread or email me if interested.
Thanks for looking,
Saurav
Hi,
I've used these with 2 speakers. My room size is around 15'x20', speakers set up along the long wall so they're about 7-8' from the listening position. I have a subwoofer, and I've tried these amps (and the speakers) both run full-range, as well as high-passed at between 50 and 80Hz. Most of my music is amplified rock, with some jazz and lighter acoustic stuff.
* GR Research Paradox 1s - small (5 1/4" woofer) bookshelves at 88dB. With these, I could get to satisfactory volume levels (80-85dB peaks) on pretty much all my music. Van Halen-like music cranked up really loud made the amps run out of steam. Midbass dynamics were satisfactory, but not breathtaking (to be expected with 8W and 88dB).
* Adire HE12.1s - larger (12" woofer) monitors at 96dB. With these speakers, the amps could easily take anything I threw at them. These speakers didn't like being fed too much bass, so I high-passed the amps when I used them with these speakers.
Other than the dynamics issue, the sound of the amps was very sweet with both speakers. My previous amp was a NAD integrated (C340), and compared to that, these amps had a much smoother midrange and treble.
Hope that helps. I'm having problems accessing my email from work, so I haven't been able to read your email yet.
I've used these with 2 speakers. My room size is around 15'x20', speakers set up along the long wall so they're about 7-8' from the listening position. I have a subwoofer, and I've tried these amps (and the speakers) both run full-range, as well as high-passed at between 50 and 80Hz. Most of my music is amplified rock, with some jazz and lighter acoustic stuff.
* GR Research Paradox 1s - small (5 1/4" woofer) bookshelves at 88dB. With these, I could get to satisfactory volume levels (80-85dB peaks) on pretty much all my music. Van Halen-like music cranked up really loud made the amps run out of steam. Midbass dynamics were satisfactory, but not breathtaking (to be expected with 8W and 88dB).
* Adire HE12.1s - larger (12" woofer) monitors at 96dB. With these speakers, the amps could easily take anything I threw at them. These speakers didn't like being fed too much bass, so I high-passed the amps when I used them with these speakers.
Other than the dynamics issue, the sound of the amps was very sweet with both speakers. My previous amp was a NAD integrated (C340), and compared to that, these amps had a much smoother midrange and treble.
Hope that helps. I'm having problems accessing my email from work, so I haven't been able to read your email yet.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.