I have a somewhat weird question. How warm is your SU-6? When I just got my SU-6, I was quite surprised by how much heat it generated. It is not exactly hot, but significantly warmer than my DAC. Kind of class AB speaker amp warm. A few weeks later today, it is pretty much at room temperature...

Hi, sorry, haven't been checking this forum for a while. I saw your postings at diyaudio.com , I'd suggest you give one more shot at the preamp forum there, which is much more popular and active than its headphone forum. For me the puzzling thing is that why it affects both channels...

Sorry, this is beyond me. If you can't get help here, I suggest you head over to diyaudio.com. Post the schematic and the findings there, I'm sure the folks there can point you in the right direction. If you do, let me know, I am interested in knowing the outcome. Like I said, I suspect mine...

Assuming the DC spikes happen simultaneously on both channels (this can only be confirmed by you), I think the only possible scenario is the power supply, since that is the only place where both channels shares. This could be due to some instability in the ±15V regulation, however I think it is...

You can not measure DC on the output jack with the relay inline, you have to tap it before it hits the E12. However, if the DC transient is too fast you might not be able to measure it with a DMM, you need a scope for that. But if it stayed on for say a couple of seconds, this you can pick it...

Btw, did you implement the regal mod? Or the higher heater current mod? Mine used to trip often if I set the B+ or the current too high. Then it happens when I used 12BH7 that draw more heater current (300mA) than stock (150mA). I suspected it had to do with power instability. But now it seems...

Years back, I auditioned an SR-60 to see if it is for me. When I heard it, I went eww. It's congested congested and harsh. They are often touted as the rock can, I happen to be not that into rock. Thus since the beginning of this hobby, I thought Grado isn't for me. Fast forward to recently, I...

This been quiet for a while, allow me to bump this up. I build this Beta 22 a while back. The transformer was housed in another chassis. I wasn't entirely happy with it, but it at least had a proper chassis. Then I ripped it apart, and turned it to this. :D

I have a pair of 5963 and they should work fine. What is your voltage between TB+L and TPL (and the right side too). If I were to hazard a guess, there is something wrong with the either the CCS or the current mirror.

I see, those aren't 4 poles electrolytic.

You can not just ignore the other 2 poles of a 4 pole capacitor. 4 pole capacitor has separate input and output leads, 2 inputs and 2 outputs. Do read about them, you most likely won't be able to use them without modification to the PCB.

That is exactly what I meant by design fault. :D Most (if not all) modern equipments have relay that can cut off output at the event of power failure/cut-off. But you can argue that it was never designed for that purpose in the first place. :)

Mine does that too, and I wonder if it is a design flaw.

Quote:   Just need to replace the output transformer with an appropriate one.

You will want to keep the wire as short as possible, while keeping the cap body away from the tube and the heat sink. FWIW, mine is a bottom mount build. I have one lead attached to one hole and connected the other end with wire. You can then place the cap body in front of the heat sink or at...