Valves in your DAC

[realysm42]

Lots of people report that tube rolling on the output tubes of their dac is an effective way to change the sound. It stands to reason that you find the ones you like the best and stock up on them - fair enough. My experience here is I changed some older valves out for the same type after some heavy use and the sound was a lot more engaging, as you might expect. I think they aged gracefully as I didn't realise anything was 'wrong' until they were changed.

The question here is what about the valve you use for power rectification; do you find that this one has an appreciable impact on the quality of sound?

My DAC uses a single EF86 for this duty and I've got a selection (some cheap, some less so). I know people are going to say try it and see (I plan to when they need changing, of course), I just want to hear other people's experiences in this area. Do all tubes have a significant (and equal) impact on sound in your system?

Thanks,

Martin

[Firebottle]

The EF86 is a low power audio pentode, not a rectifier. Do you have the wrong type number?

[realysm42]

It's not the part number that's wrong, looks like my terminology might be however, according to the website:

"Analog board contains three regulated power supplies, one for the digital board main supply, one for the output stage valve heater supply, and a valve regulated high voltage supply using high voltage mosfet and EF86 pentode design. Low noise HT supply ensures ultra low analog noise floor."

Rectify/regulate, it's all the same to me

[Firebottle]

Ah..got it now. I would have thought it wouldn't make a smidgen of a difference due to using a MOSFET as the pass element in the regulator circuit.

The only thing is to try it and see.

[StanleyB]

Rectify/regulate, it's all the same to me

Let's hope you don't try to regulate a supply with a full wave bridge rectifier then.