Pictures of your diy Pass amplifier

[adason]

Are you using the same voltage for all the amps?

I am in the process of ordering my transformers, started with wanting one with 24X2 + 12X2, same current rating for all four, so that I could use either 12V, 24V and 36V.

But when I analysed it, it doesn’t appear to be as cost effective as I think, for:

1) the full transformer rating will only be utilised when I use 36V x 2, when I use 12 and 24 I will only be using 1/3 or 2/3 of the rating, so if I want 600VA for 24V, I will have to spec 900VA for the transformers ==> defeating the purpose of cost savings;

2) transformers with multiple voltages output will have to be made to order, which is actually quite costly, sometimes it may be cheaper to buy another transformer.

My other alternative is to have transformer with output of 48Vx 2, I could connect the 48V in parallel, and with floating earth method I get about +- 32Vdc, or connect that 48V in series and get 64Vdc.

Do you have a cost effective way of having multiple voltages to play with different amp at different time? Without having to resort to a Variac? Which is another costly thing to pay for.

Maan, woow, talking about overthinking. Just chill man. Multiple voltages? Variac? Custom windings?
Just build power supply for F4...400VA with 2x18VAC, after rectification, filtration, and load gets you about +/_24VDC. You can power F5, M2, AlephJ, J2, AN39 and other. If you need any other voltages, build another.

 

[audiosteve]

Hello @adason, what connector do you use to get power from the outboard supply to the amp?

 

[adason]

Barrier terminal strip

 

[myleftear]

Speaking of procedure, and space…

 

[von Ah]

Barrier terminal strip

Pure DIY FAB spirit.

@audiosteve, if you haven't, read the outboard PS thread. Lots of good suggestions and approaches there.

 

[adason]

If you want to go fancy, you can get barrier strip with translucent plexy on top

 

[adason]

Some First Watt amplifiers sans their power supplies patiently waiting their turn in circulation.

 

[Jacruzer787]

I wonder if the xlr connector, similar to pearl 3 would also work?

 

[Stanislav]

If you meant XLR for DC power, yes, that works great.
I've been using them for a long time for MoFo monoblocks @ 2A, Zen Lite headamp, Pearl I phono, B1 pre and many others.
DC up to 48V, for higher voltages like in tube gear I go for Neutrik Speakons.

 

[Jacruzer787]

I think that is an excellent solution for outboard ps. Simplify swapping out different amps, predicated that amps are running same voltage…

Sorry thinking out loud here…. Cheapskate over here trying to think of cheap ways to have more amps… 🤣

 

[myleftear]

This is a proven, almost official, concept

 

[NE WAY]

Maan, woow, talking about overthinking. Just chill man. Multiple voltages? Variac? Custom windings?
Just build power supply for F4...400VA with 2x18VAC, after rectification, filtration, and load gets you about +/_24VDC. You can power F5, M2, AlephJ, J2, AN39 and other. If you need any other voltages, build another.

Some First Watt amplifiers sans their power supplies patiently waiting their turn in circulation.

Impressive collection!

 

[NE WAY]

I think that is an excellent solution for outboard ps. Simplify swapping out different amps, predicated that amps are running same voltage…

Sorry thinking out loud here…. Cheapskate over here trying to think of cheap ways to have more amps… 🤣

Me too

 

[NE WAY]

Speaking of procedure, and space…

Curious as to why transformers is in the second level, rather than right at the bottom, since it is the heaviest.

Are those Toroidy standard or audio grade transformers? How do they compare to Sedlbauer or Talema?

 

[myleftear]

They're Audio-grade. No Idea how they'd compare to Sedlbauer or Talema. But all 3 have a good reputation.
They're in the second floor for space-issues, as the IEX and front-switch couldn't to be sitting "somewhere in the plates". Below, at the 1st./ground-floor is Mark's, uhm, H9KPXG "softstart".
(Yes, the amp is reversed on the desk, the cap-bank is on the top, toroids in the middle, 230V-stuff at the bottom, so the H9KPXG is mounted feets-up...)

 

[NE WAY]

Some First Watt amplifiers sans their power supplies patiently waiting their turn in circulation.

There are a lot of amps! I am just trying to build a pair with big heatsinks and housing several amps in them, sharing the heat sinks and PSU.

 

[adason]

Oh, i got lot more. Many in modushop cases. This is just one rack.

 

[NE WAY]

A Different Zen V9

After smoking my V9 circuit a couple of years ago I tried again and this time it worked so I made a decent case for it.

beautiful casework

 

[von Ah]

Newest heater in the stable. @schultzsch’s Boo OS with LUs.

This one was a long time coming. Very generous transcontinental work and support from Romania.

It took me so long to get this done that Gianluca changed the heatsink rails at Modushop in the time since I started with this amp. My heat spreaders no longer fit, so I improvised with spacers. The chassis is now is a Tie-Fighter.

I have barely enough gain with my Iron Pre to get this to normal listening level, so some gain structuring is in order. However, for now, it sounds sublime. Quick assessment is it sounds like it’s between my K1530/J201 F5 and my Scryer. VERY respectable company. I think my favorite amps list now has three entries.

Thanks again, @schultzsch !

 

[schultzsch]

Looking good

it sounds like it’s between my K1530/J201 F5 and my Scryer

If the vds on the lu is set low it will sound closer to the scryer, set it higher and will sound closer to the f5.