And now it's the MA-1s in the system and with fewer output tubes

jeffreybehr

Well-Known Member
Dec 16, 2018
185
141
130
80
Phoenix, Arizona USA
www.flickr.com
I believe most A-S owners understand that their amps can operate succesfully without some of their output tubes (OTs) as long as they're removed in left-half/right-half pairs.. My MA-1s are now operating quite well with only 2 pairs of OTs per amp instead of their original seven pairs.. Probably in October, when Phoenix is no longer in summer, I'll add a couple pairs per amp.
2019Jul03_1040335_w 2 pairs OTs_1600w.jpg


After some consideration over a couple weeks including realizing that I still fantasize about the Revel Ultima2 Salon2 systems (with their 4-Ohm impedance), I decided that the MA-1s with their much-higher power were more flexible than the M-60s, so back in they went.. I also bought (from Mouser) new output-stage PS caps (Nippon Chemi-Con 27000/160s) which will be bypassed with Blackgate 470/160s and the SoniCap Platinum (TFTF) 1uFs already in the amps.. I'll select the four closest in capacitance.
2019Jul02_1040332_6 + 4 new PS caps_1600w.jpg
More pics later.
 
Last edited:

jeffreybehr

Well-Known Member
Dec 16, 2018
185
141
130
80
Phoenix, Arizona USA
www.flickr.com
Is there any quality degradation?

Not that i can tell.. Of course, the amp's output impedance increases, perhaps significantly with fewer than half the number of output tubes installed.
 

About us

  • What’s Best Forum is THE forum for high end audio, product reviews, advice and sharing experiences on the best of everything else. This is THE place where audiophiles and audio companies discuss vintage, contemporary and new audio products, music servers, music streamers, computer audio, digital-to-analog converters, turntables, phono stages, cartridges, reel-to-reel tape machines, speakers, headphones and tube and solid-state amplification. Founded in 2010 What’s Best Forum invites intelligent and courteous people of all interests and backgrounds to describe and discuss the best of everything. From beginners to life-long hobbyists to industry professionals, we enjoy learning about new things and meeting new people, and participating in spirited debates.

Quick Navigation

User Menu

Steve Williams
Site Founder | Site Owner | Administrator
Ron Resnick
Site Co-Owner | Administrator
Julian (The Fixer)
Website Build | Marketing Managersing