gc335 is an excellent seller. I received the Asgard and Bifrost quickly, both in perfect condition, well-packaged and for a good price. Recommended Head-fi seller.

This thread is for those who prefer to use their Bifrost Multibit in NOS mode. I'd enjoy hearing about the experiences that led to your decision. Reminder: Bifrost 1 (not BF2) is digital filterless (and non-oversampling) when fed 176.4kHz and 192kHz input sample rates. To avoid potential...

I listen exclusively to classical music. I've tried SS and tube amps. Tube amps are the way to go for classical. And not just tubes but a particular type of circuit: what you really ought to want is single-ended triode (not push pull) and, if possible, a plate-follower or grounded-cathode output...

Quote:   Absolutely right, of course. My mistake, mikeaj. White noise is not a sine wave, since it has equal power in all frequencies.   Quote:   Re/ADC: got it. (1) With regard to ouput, I was thinking that white noise generated by software on a laptop would be fed via a DAC...

Quote: I appreciate your point, nikongod, about the relevance to design of making cost-efficient tradeoffs. That is almost surely the reason the DV designers made the choice  of 30uf caps rather than ones with a greater value.   As I suggested in my comment about the 30uf caps...

  Quote: Hi mikeaj. I'm unfamiliar with the acronym ADC; what does it stand for?   I understand what you say about simply setting the amp's output at a level such that clipping of the line in doesn't occur.   When you say "measure the voltage at the output via a Y-splitter," do...

Hi digger945. Given our previous discussion of the DV336 problem, it looks like we're beginning a healthy head-fi conversation. That's surely a good thing.   I am wanting to test the 336, but with the express purpose of comparing its handling of an input signal with my MG Head Mark II OTL...

I've been curious about analyzing my headphone amps for linearity. This is a good way to begin to understand a large part of the reason why some amps sound better to us than others.   To those who have done this, what is needed besides spectrum analyzer software? In particular, we need a...

Problem solved.   Just received the cheap but working 6080 I ordered last week so that I can rule out the possibility of a bad output tube as the cause of the problem. Put it in, and voila, right channel working perfectly. So it looks like a bad half of the 6AS7 was pulling power from one...

I see. So a shorted half of the output tube might be giving us the difference in readings at the input tube.   Sometime next week (once I receive the tube I've ordered), I'll be sure to let you know what the result is of trying it in the amp.   As for the test you've suggested, I'm not...

Another thought: this is a direct coupled amp, so no cap between the stages. So do you think that a bad output tube could possible screw up the voltage readings taken at the front tube?

Ah, voltage drop. Right. My mistake.   I've just measured with amp plugged in and tubes in place. The two channels are significantly different for both the plate and cathode resistor voltage drop.   Good channel: plate 79v cathode 2.6v   Bad channel: plate 160v cathode .29v...

Okay, done: 30k ohms across each of the plate resistors, and 1k across each of the cathode resistors. So, still no difference between channels. And just for the heck of it, I measured for the output tube: 1k across the cathode resistors. All measured with tubes in and caps fully discharged.

Yes, I've measured with tubes and without tubes; the measurement is the same in both cases.   Given the buzzing in the bad channel, do you figure there's some sort of grounding problem with the channel?   Also, I'm curious what your train of thought is about possible causes. That is...