I just had the opportunity to compare Op amps in the Pass WHAMMY which I find sounds better than the crack/ speedball - really- no kidding.
Comparing the OPA627 (you need two so about $60) vs OPA2017 ($20)
Using the OPA627 is a bit more clearer and articulate across the spectrum - open spacious, clear and deep bass - like opening a window to the OPA2017
I if had just the OPA2017 in the WHAMMY - I already determined it sounds better than the Crack w/sb and the Emotiva Bas-X 100 - and the two MUSES8920 op amps in my TEAC UD-301. BUT - The OPA627 dual chip design is by far best especially in the WHAMMY. I have used many amps before this- and for a single ended amp this beats even the Bottlehead Mainline 1.1 and the Crackatwoa as well. The closest the Bottlehead comes is the crack w/sb and power cord upgrade but still not revealing the last details that the Whammy provides my HD600. I can not comment why the power cord on crack makes such a nice difference but it does-
I have rotated my ER-4 Micro Pro P and S editions in the WHAMMY and its a perfect match as well. Unlike the Crack or the Emotiva which pale when using these critical ear phones.
I also used the Sony MDR-V6 and MDR-2506 which usually sound terrible when things aren’t right- they are not the best for music long term though on any system.
I also used the Master Dynamic MW30 and they sound excellent with WHAMMY as well.
very impressed.
Caveat to WHAMMY- no output RCA and no front power on off switch, and you need to rely on a professional builder- I got mine from James the HeadAmpBuilder
I can not believe how good this PASS design is- I cant stop listening to music!
Comparing the OPA627 (you need two so about $60) vs OPA2017 ($20)
Using the OPA627 is a bit more clearer and articulate across the spectrum - open spacious, clear and deep bass - like opening a window to the OPA2017
I if had just the OPA2017 in the WHAMMY - I already determined it sounds better than the Crack w/sb and the Emotiva Bas-X 100 - and the two MUSES8920 op amps in my TEAC UD-301. BUT - The OPA627 dual chip design is by far best especially in the WHAMMY. I have used many amps before this- and for a single ended amp this beats even the Bottlehead Mainline 1.1 and the Crackatwoa as well. The closest the Bottlehead comes is the crack w/sb and power cord upgrade but still not revealing the last details that the Whammy provides my HD600. I can not comment why the power cord on crack makes such a nice difference but it does-
I have rotated my ER-4 Micro Pro P and S editions in the WHAMMY and its a perfect match as well. Unlike the Crack or the Emotiva which pale when using these critical ear phones.
I also used the Sony MDR-V6 and MDR-2506 which usually sound terrible when things aren’t right- they are not the best for music long term though on any system.
I also used the Master Dynamic MW30 and they sound excellent with WHAMMY as well.
very impressed.
Caveat to WHAMMY- no output RCA and no front power on off switch, and you need to rely on a professional builder- I got mine from James the HeadAmpBuilder
I can not believe how good this PASS design is- I cant stop listening to music!