I think I asked this question sometime back, but didn’t get any response. How do I figure out the generation / version of the amp, whether the original or upgraded, second generation. My serial no is 03B0817. I bought it used.
I have tried to do that before, but couldn’t find any difference in looks between the one on Massdrop and mine. In one of the massdrop photos, the middle black box on the back seems slightly taller than the other two, while mine are all equal sizes. Other than that, there is no visible difference. However, the very first version of the amp from 2010 (pictures posted in the first post in this thread) also looks identical to the massdrop version, except for the slightly taller middle box.
Just checked, my amp doesn't have those 2 green capacitors in the center of the board. From what I remember when I was researching this amp, the previous internals update happened in 2014-2015 and was an upgrade to the resistors, which are just above the green capacitors. That's the version I have and the consensus here was that it sounded noticeably better than the earlier iteration IIRC.
Good excuse to remove the dust from underneath the amp anyway
edit: considering there are massive capacitors on each channel's circuitry, in the big black boxes, how big of a difference would two smaller capacitors really make?
Bendix 6080WB: rolls off the treble a few db, i think it also increases the mids and bass by a fair bit. Made listening to the DT880 slightly less painful, but the treble spikes were still there. I tried with the 650s and compared to the Cetron/Tung-Sol 7236, the Bendix are more muddy sounding. Sennheiser 650s and 7236 = great!
The old version and the new version use materials very differently. 1. The new version of the tuning capacitor is changed to green 10UF, 2. The power supply resistor is changed to CADDOCK, and the output resistor is changed to the custom-made non-inductive resistor.
The old version is a yellow metal resistor that can be used to see if the photo can't be sent. Http://www.diybuy.net/forum-28-1.html
The old version and the new version use materials very differently. 1. The new version of the tuning capacitor is changed to green 10UF, 2. The power supply resistor is changed to CADDOCK, and the output resistor is changed to the custom-made non-inductive resistor.
The old version is a yellow metal resistor that can be used to see if the photo can't be sent. Http://www.diybuy.net/forum-28-1.html
Thanks very much for the clarification. It might be helpful, if you can list the revisions and improvements in the 339 over the years and the corresponding serial number ranges. That way, people can know which versions they have. Also, is it at all possible to upgrade an older version to the newest one, either by sending the amp to you (difficult), or purchasing the parts (and instructions) from you. I have basic soldering skills.
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.