@Catcherfly I plan to use the balance hole for this... Not sure if this is possible, but that's the basic idea. I dont think I will ever use the balance function (plan to hard wire it).
Pretty busy with daily work, so not able to spend time realizing this idea. But in general, I believe TU-8550 will be a nice upgrade from my TU-8500. So looking forward to build it.
Pretty busy with daily work, so not able to spend time realizing this idea. But in general, I believe TU-8550 will be a nice upgrade from my TU-8500. So looking forward to build it.
Could this be added to provide remote volume:
https://www.parts-express.com/Line-...oard-with-Remote-6-12-VDC-320-6012?quantity=1
https://www.parts-express.com/Line-...oard-with-Remote-6-12-VDC-320-6012?quantity=1
The Az-cap is manufactured with aluminum foil, which is about 1/10 of the price of copper foil. CuTF is made with PTFE, which is 10x the price of the Jupiter dielectric.
I bought my TU-8550 a year ago and just recently had the time to put it together. After completing the kit, I'm having an issue with the right channel output. I've got some disconcerting readings: Test point 14 is showing -11.87V (should be 1V), TP16 is showing 196.2 (should be 125-145), TP18 is 160.9 (should be 110-130), and TP20 is 160.8 (should be TP18 + 2). I re-soldered all of those connections just to be safe, and checked the ohms on the un-powered resistors themselves (R224 (12k), R227 (100k), R228 (220k), R229 (47k)) and they all gave a proper reading. Sadly that's about as much as I know to do, does anyone have any suggestions of how to try and resolve this? Thanks in advance.
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Thanks - I actually wrote Elekit last evening not really expecting a reply and they got back to me already with a suggestion that it could be the heating element on tube V202, possibly caused by a bad solder joint on pins 4 / 5. I'll post again if that solves it.
-- upon closer inspection it looks like the tube itself is bad, there is white oxidation that I could not see before, presumably from a gas leak?
-- upon closer inspection it looks like the tube itself is bad, there is white oxidation that I could not see before, presumably from a gas leak?
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The original ALPS 4 channel pot has a linear variation of the resistance and TKD has logarithmic variation of the resistance. The TKD 4 channel pot can't be used in the TU-8550, because VR1 is linear (100k B) and mounted as voltage divider.
The TKD pot are "stereo volume (real log) control".
The ALPS datasheet mentions B version for tone & general (e.g. voltage divider) and A version for volume.
Managed to find a music store here with some tubes in stock, amp is working perfectly now. What a difference this makes to my 8800! Sounds phenomenal ... I wish I hadn't talked myself out of splurging for the nice capacitors from VK. Time to go for the 8900 maybe... Tube was a dumb oversight on my part, should have been looking more closely (oxidation was barely visible from the top... that's my story and I'm sticking to it), but it's good to know Elekit has such good customer service.
