• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

#26 pre amp

iko

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Joined 2008
A discrete shunt regulator like the SSHV2, in my opinion, will shine when there's more variation in current, on account of its low output impedance. I've a big fan of shunt regs, as you may know, and I've dedicated a significant amount of time to improve on Salas' initial design. The VR tubes don't come close to the discrete shunt reg as far as low output impedance is concerned.

Edit: for a 4P1L, 6V6, D3A, or any other tube that draws more than 10mA current I'd be more tempted to use a discrete shunt reg. I think it'll behave better on transients.
 

iko

Ex-Moderator
Joined 2008
And I'm sure that your phono is excellent! I have nothing but respect for your designs.

That being said, the regulation itself isn't what I was emphasising. Low noise and low output impedance supply is the real advantage from that particular shunt regulator. Imagine flat output impedance below 1mOhm, past 20kHz. Low noise you can get with chokes in the supply. Low output impedance too, but the chokes must be quite large to achieve that ($$). I never got a chance to compare, but I would not be shy to put a good discrete shunt regulator next to a choke supply for this particular application (phono+high-ish current input tube).
 
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PSU very near 26 still no noise:D
 

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Nice looking build Merlin.. :D

About 12yrs ago I initially tried the VR150/0D3 in my early 26 based line stage design, but found the noise from the gas tube to be excessive in my application.. The plate to line transformers in question were UTC HA-133: 5:1 15K:600 which I am still using. The power amps had modest gain of about 10dB but were driving a rather efficient JBL speaker system (>100dB) wondering now whether I just had a batch of particularly noisy gas tubes.. (NOS) My opinion at the time was that it was almost quiet enough and had the speakers been about 6dB less efficient all would have been well.

My current speaker system is also over the 100dB mark so all of my electronics have to be extremely quiet.