1. First, sound quality--resolution/transparency and smoothness (= nonedginess)--are excellent, even with brand-new everything.
2. Have had some problems with lack of good contact with tube sockets. Had lots of trouble getting one amp to null its DC offset. Thought it was mismatched output tubes or even bad frontend tubes. Played with 16 output tubes (hereafter OT or OTs) and several frontend tubes (FETs)--original Chinese and old Tung-Sol roundpates. Sometimes the cathode follower's filaments wouldn't glow. Eventually worked out a sequence of loading input tubes into the amp and then pairs of OTs, and all has been well in both amps for a couple days. (I experienced the problems in only one amp, I experienced NO OT-internal-fuse blowings, and Ralph was very helpful.) My lesson learned--TY, Ralph--is that the Chinese tubes have slightly larger pins, and sometimes the socket's contacts don't make good contact with my old tubes.
3. Have installed new Cardas CCGR bindingposts, new solid-silver wires to the cap terminals, new Furutech FP-901(R) RCA jacks, two 1uF SoniCap Platinum output-stage-PS bypass caps in each amp, and three strips of SoundCoat the thicker...see link...on each bottom cover. IMO the chassis rings too much, and I'll be adding more of that stuff. (IMO vibrating resistors, capacitors, wire, vacuumtubes, etc., do NOT add to the sound quality, they all diminish it.)
4. I THINK the first serious improvement project I'll do is to replace the inexpensive 100/350 'lytic caps in the frontend's powersupply with BlackGate VK-series 150/350s*, bypassed with 0.47uF Platinums. ... But that's a big project, and probably it'll take me weeks to start that. Then I'll replace the output-stage PS caps, and for that I have a bunch of BlackGate 470/160s*.
* that I've been saving for many years
Tin-eared audiofool, large-scale-Classical music lover, and damned-amateur fotografer.
William Bruce Cameron: "...not everything that can be counted counts, and not everything that counts can be counted."
Edits: 04/23/16 04/23/16 04/23/16 04/23/16 04/23/16 04/23/16 04/24/16 04/24/16 04/25/16 04/26/16 04/30/16 04/30/16 05/02/16 05/02/16 06/19/16 06/19/16This post is made possible by the generous support of people like you and our sponsors:
Topic - My experiences with new M-60 Mk.3.3s, good and not-so-good - jeffreybehr 14:28:07 04/23/16 (11)
- RE: My experiences with new M-60 Mk.3.3s, good and not-so-good - ozzyboy 12:07:04 03/16/17 (0)
- Winter-'17 bump. Got the new front-wall dampers installed... - jeffreybehr 14:53:40 02/27/17 (0)
- My latest adventure with these amps had one OT blowing its internal fuselinks. - jeffreybehr 17:34:29 07/07/16 (0)
- The system sounds better all the time. - jeffreybehr 01:03:43 05/13/16 (0)
- Got one more amp finished to an initial degree. - jeffreybehr 22:24:58 04/26/16 (2)
- RE: Got one more amp finished to an initial degree. - kbsp 08:48:51 07/08/16 (0)
- RE: Got one more amp finished to an initial degree. - Leadfoot 18:51:10 04/27/16 (0)
- RE: My experiences with new M-60 Mk.3.3s, good and not-so-good - Lew 10:04:10 04/25/16 (2)
- Lew, of course the amps came with feet; I removed them. :-) - jeffreybehr 18:43:40 04/25/16 (1)
- My mistake... - Lew 21:51:59 04/25/16 (0)
- RE: My experiences with new M-60 Mk.3.3s, good and not-so-good - Cousin Billy 08:02:11 04/25/16 (0)