Are they SE amps or PP?

I am NOT an expert on valve circuits nor on PSU's but I do like to absorb general principles, that are supported by empirical evidence.

Viz? A good high-storage PSU sounds better than a good but VR-limited PSU. Ripple will be a whole lot lower, for a start.

And, that SS diodes offer you the possibility to substantially increase the energy storage in a valve amplifier, which VRs don't like. If we square 50 volts we get a factor of 2,500 if we square 300 V ( 6 times the volts) we get a factor of 90,000. Divided by 2,500 we get 36 times the storage.

In other words a quite small valve amp - in WPC terms - can have a far stiffer PSU than most BIG SS amps. And IMO&E far better bass. Less dry and tight perhaps but lots of slam. If it's a PP NFB amp then the advantage is considerable.

That is I am not claiming that good SS diodes - SRs / Schottkys - snubbed or not sound better than VRs, but pointing out that VR's do limit the stiffness we can achieve in a PSU.

Peak Inverse Voltage is the limitation VRs have.

I don't see how a VR can to do anything special to the sound a PSU gives us, but I know that a VR will limit the volts we can get and severely limit the amount of storage we can have. I also know that their use in guitar amps is because of the sag they are able to give. No Hi-fi amp needs sag.

So I ask, why do it?

Back to your amps?

It may, as you think possible, be overkill to increase the storage of your 1 watt amps. I don't know.

While it is quite possible to have too much storage which can pulse the PT too much, I haven't heard any negative consequences from these big PSUs in the LEAK St20s. The PT in these is probably a bit stressed in hot climates, so it could have been an issue.

I don't have an OEM LEAK St 20 circuit diagram to hand, but they had IIRC, three? or four 32uf? (small ones anyway) capacitors, circuit-value wise. Two in one can I think.

We used 4 x 470uf 400V dark-brown Nichicon caps in the bass-duty amp and 3 in the mid-treble amp. The last two in each amp are bypassed with MKP and MKS caps.

Warmest

Tim Bailey

Skeptical Measurer & Audio Scrounger

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Follow Ups Full Thread

Topic - Bad 5AR4 - Garg0yle 13:03:34 08/27/15 (22)

RE: Bad 5AR4 - Alpha Al 09:48:29 08/28/15 (1)

RE: Bad 5AR4 - Garg0yle 10:29:45 08/28/15 (0)

RE: Bad 5AR4 - Paully 17:45:40 08/27/15 (0)

RE: Bad 5AR4 - krankkall 15:46:09 08/27/15 (0)

I had very bad luck with Sovtek 5AR4's (nt) - gusser 14:16:50 08/27/15 (1)

RE: I had very bad luck with Sovtek 5AR4's (nt) - Eli Duttman 18:53:02 08/27/15 (0)

RE: Bad 5AR4 - Jim McShane 13:14:02 08/27/15 (15)

RE: Bad 5AR4 - Garg0yle 13:33:13 08/27/15 (14)

RE: Bad 5AR4 - Garg0yle 19:48:32 08/27/15 (13)

RE: Bad 5AR4 - Jim McShane 05:47:20 08/28/15 (0)

US made NOS are good, too - FenderLover 04:46:20 08/28/15 (11)

RE: US made NOS are good, too - danlaudionut 03:59:55 08/30/15 (0)

RE: US made NOS are good, too - Garg0yle 08:58:02 08/28/15 (8)

why do you HAVE to have a valve rectifier, anyway? - Timbo in Oz 02:20:48 08/29/15 (7)

RE: why do you HAVE to have a valve rectifier, anyway? - Garg0yle 19:17:18 08/29/15 (4)

A slow enough turn on can be achieved in lots of other ways - Timbo in Oz 21:17:44 08/29/15 (3)

RE: A slow enough turn on can be achieved in lots of other ways - Garg0yle 23:22:00 08/29/15 (2)

Are they SE amps or PP? - Timbo in Oz 00:36:33 08/30/15 (1)

RE: Are they SE amps or PP? - Garg0yle 17:26:33 09/04/15 (0)

RE: why do you HAVE to have a valve rectifier, anyway? - Eli Duttman 09:30:23 08/29/15 (1)

IME using SR SS rectifiers - snubbed - improved the bass a LOT!bit more power - Timbo in Oz 15:00:33 08/29/15 (0)

RE: US made NOS are good, too - Cleantimestream 08:32:40 08/28/15 (0)

Follow Ups

Are they SE amps or PP? - Timbo in Oz 00:36:33 08/30/15 (1)

RE: Are they SE amps or PP? - Garg0yle 17:26:33 09/04/15 (0)

Are they SE amps or PP?

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