Running Truepath below +/- 35 V

[fdeck]

Is it possible to run the Truepath on lower supply voltages? I assume it is just a matter of resistor choices, right? I would like to try it out, while putting off upgrading my existing power transformer which I bought for an AMP1 board.

Cheers!

Francis Deck

[audiophool]

The 3020 data sheet says the minimum supply voltage is +/-15V. There are performance curves (THD+N) for 23V but at this voltage it's only a 20W amplifier.

Tim

[BddB]

Yes, it is possible to run on lower voltage and yes, it's a matter of resistor choices.

[u]35-60V:</u>
1.07K, 1% R107 R110 R207 R210
13.3K, 1% R106 R109 R206 R209
392K, 1% R4
1.18M, 1% R5
422K, 1% R6 R7

[u]21-39V:</u>
1.13K, 1% R107 R110 R207 R210
8.25K, 1% R106 R109 R206 R209
249K, 1% R4
750M, 1% R5
267K, 1% R6 R7

/Benn

[nominis]

> Yes, it is possible to run on lower voltage and yes, it's a matter of resistor choices.

I have a spare 2*24V (600VA) toroid. is it possible to get Truepath kit delivered with the corresponding resistors?

2nd question: will the (to be announced) PSUs for Truepath work with this transformer?

[BddB]

I don't know whether Jan is going to supply these resistors.
On the other hand, these 12 resistors are not that expensive that they will ruin your economy.;)

The PSU for Truepath will work with transformers up to the capacitors max.voltage/1.414 (which I think is 63V/1.414=~44V)
/B

[nominis]

> these 12 resistors are not that expensive that they will ruin your economy.

but minimum order and s&h costs a multiple; not everybody has a parts shop nearby.