Yunick said:
I haven't had the time to fiddle with it more. The output is still high (i think 6V p-p) because of the buffalos higher mA output. This caused my preamp to clip..
For now I use the built in volume control in the squeezebox then feed direct to my power amp. This is for me a very good combination. I use mainly Flac, but sometimes mp3 also. But never during critical listening. With 88db spks and 15db gain in poweramp full volume on the squeezebox is just right
The sound is just awesome! Powerful describes it good.. Alot of drive
Yunick - I'm not at home , reading from "strange" PC ;
can you give me direct link for schematic you use , maybe I can help with output level issues .......
Luke said:what you might like to try is shunt some of the excess current to ground, perhaps a pot would be useful so you can experiment with what value to use?
BTW how do you measure the output, do you have sinewaves you can look at with a scope?
Yes a shunt would work. I might try that. The output voltage number came from simulation. I have only tried it with my UGS preamp. Over at UGS adventures I read that max input of the UGS preamp is +/-4V. If I lower the volume on the squeezebox it works fine. But not with my CD-player or Turntable. The scope is still at work but I can measure it next week.
Zen Mod said:
Yunick - I'm not at home , reading from "strange" PC ;
can you give me direct link for schematic you use , maybe I can help with output level issues .......
Zen Mod Good to see you here
I used this Schematic and tried the circuit with half values of R15 (1.6k) / R16 (750r). From what I understand those resistors set bias and gain?
I would be very happy to if you could take your time and have a look
It looks like R17 is the I/V resistor which is what you would want to adjust to change the output level. The 1.5k that is there would suggest it is setup for a TDA1541a with 2mA output current. I would leave the values of R15 and R16 alone, but I'm not extremely familiar with the D1 stage.
Yunick said:
........
instead R17B use two resistors of 750R in series
then solder C3B to their mid point
make same game with right side out - with R17A and C3A
that way you'll have 50% of present output
that's easiest way of decreasing output without going too deep ;
btw- take a look at CeeVee's Drekling I/V stage (Shanling thread in Digital) - cheap and worth trying
...... Change R17.....
Thanks alot guys!
Zen Mod, I'll try your suggestion asap. That Shanling thread is a monster But i'll take a look.
Edit: I thought you talked about the shanling clone thread by Peter Daniel..
......instead R17B use two resistors of 750R in series then solder C3B to their mid point .....
I'm happy to report that this worked very good The values may be tweakeb a bit.
I'll also try Luke's suggestion asap.
Thanks guys for your support.
Hi there! I build me the IV stage in an parasound 1500 dac. Its hardwired. I connected the board to the pcm63PK and measured on the input 965mv and the output is drifting between 10mv and -4mv. Should I use the cermet pots to bring the input down? I connected the jumpers. Before I did that, offset on in and output was drifting from 60mv to 45mv on the inputs and outputs, but after an hour offset was at all points 0 mv, and there was no music. The cdplayer locked. Can I give it a try? Or will I destroy something. Grtz Teake
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