jose

"Out of Africa" beautiful history and beautiful music.

Why don´t you buy a good matched quartet and tests? You have several websites with good prices for JJ EL34

Used a separated PSU (with a LM7912, LM317 or LM350 for example) If you're careful, you can use the floor of the box as a heatsink. For 300vDC, I used parallel resistors. I think it's even better than using only one resistance due to the heat dissipating.

I think the offset depends more of the well matched tubes (in my case it was like this). This amplifier needs a very well matched octet and sorry but I think your valves are very badly matched. Regardless of this, you have to raise the voltage to 300v. I was working for a while with 290 volt but I finally increased it to 300v as it should be. I use a separate PSU for the heating filaments. I recommend that you carefully read the thread (especially the last post) so that you familiarize yourself with all the information there is about it.

If you allow me to comment, I think you have done well. Having complicated situations at work is very hard I was dating for a few years with one of my colleague and when we broke (things in life) the situation for some years was quite tense. We are currently working together and the situation has normalized but it is true that for a while we both had a really bad time.

Here when you measure both pins (same channel) you are measure the balance between - and +. If you want to measure offset you need to check each output with ground reference. Of course Maybe I'm wrong but if you have dudes about this you can use the search oprtion and read some many interesting treath about electrostatic amps. Are you using the LV for the heating filaments?

Yep, each channel with ground. Sorry I got confused (HV vs LV) I used a large headsink on my Square maybe you can used this (mouser reference 588-EV-T220-64E ) on LV

I answer based on the little knowledge I have. 1. Yes 2. You need lower resistor a bit 3. Yes 4. offset is measured with each channel with respect to ground. I'm not sure what you're doing (I think you're measuring the balance) 5. I use a large heatsink. maybe it would be convenient for you to think about that when you do your chasis. First check the offset, if it is low and the Bias is correct you should not have problems connecting your stax.

Thanks Stan ! You made me dream of a world full of fantasy, with super heroes, villains and stories from other parallel worlds. This world is now a sad place without you, without your humor and your imagination. Luckily you left us a great legacy, your super heroes and your villains today cry for you ... and me too.

Nice. Thanks !!!

Happy Bithday!!!!

Yesterday I was listening to the Square Wave with different headphones (hd800, W5000 ....) and I was wondering if the output impedance changes when changing the gain (Low to High)? I understand that if he does it, I do not know exactly how much or if the change is very radical.

Descansen en Paz

A classic álbum (Vinyl re-edition ) with my Square Wave and HD800:

Very interesting this "protection" system.

Good reflection Sechtdamon

I'm so sorry Brent.

I ask from ignorance. I have the Dynalo MkII "normal" (TH components with SMD sand) and if I remember correctly, transistors were 40~45ºc and I already seemed very hot for to be SMD. I think the maximum temperature of the sand is about 150ºc but I wonder if this will not be bad for the other components or the pcb.

102ºc is not a bit overkill?

Heal quickly!

I had not had time to listen to this. For a moment I thought I was wrong and that it was a Zepp record. In some cuts, the voice is almost identical to that of Plant. Good discovery. Thank you

Pianist Bugge Wesseltoft, bassist Dan Berglund and computer whiz Henrik Schwarz. "Trialogue"

My new Di2 with new battery model, Dura Ace chain and d-fly.

Is there much difference between 10k vs 50k? for balanced it´s easier to find 10k pot.

I'm not sure if that's Ray's amp. I have not found documentation about the Blackhole on "Stax mafia circuit boards", only references to the dark/dork star.