Just wanted to thank George for ordering more of these boards. Also Wall of Sound for the amazing write up and build guide. I am very happy with my finished product. This is my second tubelab build behind the sse which has been in my main system for at least 10 years.
I ended up getting a few cheaper El84 Russian military spec tubes off eBay, $30 for a quad and had the rest of the tubes from my other amp for testing. All voltages and tube dissipation seem good now. I ended up throwing in my Genelax Gold Lion tubes. I can't believe how expensive some of these tubes have become!
One last question as I am in the final stages of buttoning this up. I have read almost all the pages in the SPP threads I can find on here but just want to verify before my luck runs out. Im sure I am overthinking it at this point but the motor run cap is confusing me. Referring to this post:
https://www.diyaudio.com/community/threads/tubelab-simple-p-p.148694/page-36
Install one wire from the run capacitor to the black secondary lead on my power transformer and the other to ground which is my red/yellow? Or both to the black secondary leads on the power transformer?
Just a few minor things left, I need to get the right thermistor as I could find the correct one in my parts stash and tidy up some wiring.
I ended up getting a few cheaper El84 Russian military spec tubes off eBay, $30 for a quad and had the rest of the tubes from my other amp for testing. All voltages and tube dissipation seem good now. I ended up throwing in my Genelax Gold Lion tubes. I can't believe how expensive some of these tubes have become!
One last question as I am in the final stages of buttoning this up. I have read almost all the pages in the SPP threads I can find on here but just want to verify before my luck runs out. Im sure I am overthinking it at this point but the motor run cap is confusing me. Referring to this post:
https://www.diyaudio.com/community/threads/tubelab-simple-p-p.148694/page-36
Install one wire from the run capacitor to the black secondary lead on my power transformer and the other to ground which is my red/yellow? Or both to the black secondary leads on the power transformer?
Just a few minor things left, I need to get the right thermistor as I could find the correct one in my parts stash and tidy up some wiring.
Attachments
Interested in the bias adjustment mod...any link I could find that?I posted this in another thread, but wanted to share my new completed Tubelab SPP here also, in case it’s helpful to anyone undertaking a similar build. Two switchable inputs, feedback on/off switch, and two mode switches (one for each channel) to choose triode, pentode or ultra linear. Special thanks to Steve (Wall of Sound) for his great article! I also used a bias adjustment mod. Works perfectly!
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