USSPA Build thread

Power Supply

I like the Salas UltraBIB but at US$25.00 for each PCB, I find it expensive.

I'm currently looking at the Texas TPS7A4701/ TPS7A3301 regulator boards sold on AliExpress.

TPS7A4701\TPS7A3301 module ultra low noise linear regulator precision operation amplification fever power supply-in Switch Caps from Home Improvement on Aliexpress.com | Alibaba Group

Has anyone used these with good results? I will precede them with CRC filters.

I'm not sure if all these low noise regulators are that much better than the old LM317/ LM337 regulators when using CRC filters:rolleyes:
 
1963 3015 is great.. It have high transient response.. For me u it a one of my favorites. Great bass dynamics no ringing. And it behaves like a higher voltage swing. Depth width is good. But it have a cleaner sound... Some people might not like. Depending on accompanying equipment. Best of all very cheap to implement.
However for China pcb.. Expect very long break in I think it's the materials they use, it have a very dead sound for quite some time , but i didn't really mind. I do prefer diy pcb when able.
My friend uses lm723 type. Gives a fuller sound.



Also use very good quality resistors.

Didn't work out too good when poor one is used. It's a very transparent sounding amp. So any single poor quality resistor will eventually stick out like a sore thumb. It's low count anyway.
 
For those who would be interested, the gerber files of my version are available.
 

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HI all.



Here are the .LAY and gerber files for the UltraBIB 1.3.
In the archive there is a REV-1 with some improvements, especially at the level of the capacitors C3 which are too close to the mosfets or then it will be necessary to choose capacitors 105 °. The best is to choose the REV-1 version.
The picture shows the initial version that works perfectly.

;)
 

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Few months later.

Much further burn in. Must have clocked around 700+ hours. Usspa is liquid. Airy. Full of emotions bloom and details. A pleasure to listen to. . As expected. Ceramic cap / China pcb supply and such takes very long time to sound good. Metal films and new transformer too.

It's not really stable yet the sound.. But those who made it.. Keep playing it... You will be pleasantly surprised! It have a tube sound yet with reserve to kick up a storm. Without sounding tensed. I'm floored.

Thanks Fab... Great stuff
 
on another factor, there is a very interesting post by Salas for those wishing to use his Mezmerise pre-amps as a power supply for the Pass B-3 as a preamp. I have taken the liberty to cut and paste his advice here:


"Don't use blue leds because noisy, just replace the fifth red led closest to rail per side with 2kOhm rheostats.
Bodge them there. They will give ample voltage range.

You may leave them in or measure what adjust resistance to rail goal each then put resistors in their place.

Its for a 45mA bias per side load. It will not move away from there, no more than few mA on line level loads.
With 18//18 Ohm 2W CC setting resistors you get +/- 200mA standing current limit on a Mez board's PSU section.

BTW Ultrabib is even better. But its not a selector + psu combo like the Mez board. Standalone shunt PSU sections."