as I have seen many pictures of very nice Truepaths with big toroids in big cases,
I want to post some pictures of my SMPS powered Truepath in its 1U case.
My aim was to build a Truepath into one of those nice 1U SlimLine-Cases from Hifi2000,
so I had to look for a slim power supply. Finally I bought an Elektor SAPS400 (same as Coldamp SPS30)
which provides 400W of constant Power and is only 42mm high. It was connected as described in
Normally those 1U SlimLine-Cases are just 40mm high, so I had to raise it with some M3 nuts by about 2mm.
The only problem with the SMPS was, that it needs a minimum load of about 30mA per rail, which isn't provided
when Truepath is muted, so I had to add two 1k2 load resistors. Without these resistors Truepath didn't unmute.
At first I also had some problems with 50/100Hz hum, which was increasing when I turned up the volume,
but after replacing the 50k volume pot with a 10k pot, the hum was completely!!! gone.
The sound is just amazing: very natural sounding and extremely dry and deep bass, even at high volumes.
With closed case, the tempreature of the SMPS and the heatsinks doesn't rise above 50C.
So I just can encourage everyone who wants to build a truepath to think about using an SMPS,
as you can get very good results and it isn't more difficult than using a traditional power supply.
the front of my Truepath:
back of my Truepath together with my self build RCA-cables :
closeup of the Truepath board (on the right side you can see the ps317 which is directly mounted on the Truepath board):