[sdiy] Arp 2600 replacement op amps

[rob]

It's heresy I know .....

The ARP modules I build have those LM301 Op Amps replaced, along with
the old carbon resistors and ceramic caps. In go the modern Op Amps,
either OP177/LT1013 for CV's or OPA134/OP275 for audio. Then metal 1%
resistors and low ESR power caps, audio spec electrolytics for audio
path and WIMA polyesters, 1% polystyrenes and low-K ceramics. Oh and
cermet trimmers.

End result - a very clear and stable design. They sound better. Customer
feedback is +++ The AM4023 and AM4075 filters rock. Yes, you need to
watch for HF oscillation on Op Amp replacement, but a bypass cap soon
sorts this out when it occurs.

There is nothing magical about the LM301. ARP used it after having
problems with Teledyne 1339's. It's eclipsed by modern Op Amps (not
1970's biFETs please), and the circuits sound better. 

IMHO 

Rob 
www.emulatorarchive.com
>>From the Dave Rossum school of audio engineering 




I want to replace the 301 op amps in my 2600 with better ones -