Quote:
Originally Posted by Sean Sullivan  Well, I finished the mods today and the units sound really good. Here's a re-cap of what I did:
U1: AD8512 on Brown Dog Adapter
U2: AD8510 on Brown Dog Adapter
U3 and U4: LM6171
C3 - C6: 2200uF/35V Nichicon HE with Wima MKP-2 bypass
C7 - C8: 220uF/50 Panasonic FM with Wima MKP-2 bypass
CR8 and CR9: Green LEDs (blacked out with sharpie)
C16: 4.7uF/63V Wima MKS-4 with MulitCap PPMFX .01uF/600V bypass
C14, C14, C20, C25, C29, C44, C49: .01uF NPO ceramic
.01uF NPO ceramic across Pin 3 and Pin 4 of U2 |
Sean, I've read that the NE5534's (U3 and U4) were already pretty good to begin with. Any reason to change them?
@All: how would putting BurrBrown OPA2134PA's in U1 and U2 change from the AD ones?
I have both a blackface DBX 166 and a DBX 160X sitting here, opened up.
Also, does one need the bypass caps for the 2200uF electrolytics and if so, where you place them? Parallel, or do you mean the 2 .01uF ceramic caps need to be replaced? (right where the wires from the transformer 'enter the board'?)
I don't have a good schematic for the 160X (my manual came without one), but the one in my 166's manual is actually readable, albeit very, very small. But nevertheless, better than the scanned ones on the DBX site.
The input coupling caps on the 166 are 3.3uF (NP?) electrolytics if I'm not mistaken.