2. tech-talk
  3. 1107569647

Tube rolling ARC amps & Steelhead

A while back I decided to try tubes. I have had an ARC Ref 2 Mk II preamp for about 2 years, a pair of ARC Ref 300 Mk II monoblocks for about 1 year, and a Manley Steelhead for 3 months. They sounded great, but it never occurred to me until recently that they could sound better - I always assumed that the manufacturers knew best when they put the stock tubes in.

My speakers are Acoustat Spectra 66 full-range electrostats, and, of course, I wanted more bass. After some investigation, I replaced the stock Sovtek 6550's in the monoblocks (8 per channel) with CryoValve 6550C's (from TubeDepot). The improvement in bass was nothing short of dramatic, and I much preferred them to the stock tubes. Nonetheless, the midrange and treble seemed to be lagging behind. After some more investigation into tube replacement options, I replaced the stock 5AR4 rectifier in the Ref 2 Mk II with a Genalex Gold Lion 5AR4, let the amps warm up a couple of hours, and then listened. I was dumbfounded at the change in sound. There was no "good bass" or "good midrange", everything just fell together with remarkable imaging and coherence, and that was with CD's and the tuner! All from changing ONE tube! I then replaced the stock 6922's in the Manly Steelhead with Mullard E88C's (following the advice of another A-gon member), put on an album, and and watched the bar further raised beyond my wildest expectations. All the sound was in beautiful coherence, rock-stable imaging, perfect balance of frequencies, not a touch of harshness, enjoyable at every volume level, like Neil Young was sitting there in the room pouring out his heart to anyone who would listen. I had a friend with me who has heard my system many times before, and he independently remarked "I can't believe it, everything sounds PERFECT!"

My question is - is this a unique experience, or have others found NOS or other tubes to make such an significant difference? I can certainly see why manufacturers don't include scarce tubes with their products, but it still amazes me that the choice of tube can affect the sound so profoundly. I would be interested to hear if others have had similar experiences.

Other equipment:
VPI Scout / Benz Ruby
Levinson 390S
Luxman T12
klinerm
tomic601's avatar
tomic601
12,886 posts
 

@astolfor in which bit of gear ? I have several tube experts i source from and trust greatly. In general I like RAM ( Roger Modjeski ) for hyper strict grading of current production tubes. His many many variable computerized testing system washes some 90% of certain tubes out. His Ultra low noise 6922 are what i use in his RM-9. we lost the genius, RIP but RAM lives on. I also use an E Bloc EL-34 of his…a Phat EL-34 for sure.

For NOS w a bias to USA, i use Andy at Vintage Tube in Michigan, somewhat tough to reach it is worth being persistant. He also is a test equipment freak and meticulous… ( sense a trend ? ) i buy many Amperex, RCA, Tele and importantly Power supply USA Tung Sol from him. A NJ 1960 Tung Sol 6550 in an ARC Ref5se is transformative.

Finally, while i am a relatively new client of Brent Jesse i am favorably impressed w some ancient Mullards i sourced recently along w some RCA long grey for a 1961 MC240 project.

Hope this helps.

Jim

tomic601's avatar
tomic601
12,886 posts
 

forgot to ask, what is your preferred seat in the concert hall ? Andy has a nice chart for relating that to brands…not perfect because of circut differences…but i find it helpful…

drbond
418 posts
 

@astolfor

After upgrading my speakers, I just didn’t like the sound of the Steelhead as a pre-amplifier/buffer. I ended up buying an Ypsilon PST-100 Mk2, and I liked that so much that I upgraded to the SE version.
However, I am still using the Manley Steelhead as a phono stage only, and I am planning on upgrading to another phono stage, as long as my demo works out well. However, I am currently using Genalex Gold Lion 6922/E88CC and Tung Sol 5687, which I guess I ended up preferring over the Philips JAN 5687’s, although I didn’t truly spend any significant time in comparison as a phono stage. I also ended up buying about 5 different 6922’s, and I think I came to the conclusion that the 6922 were not worth speding alot of money on, because the sonic improvement wasn’t very marked with the expensive 6922's, so I used the Genalex.

astolfor's avatar
astolfor
317 posts
 

@tomic601 Hello Jim, thank you for responding!! 

I want to roll tubes in the Steelhead, and my yet to come Pathos Heritage.

I am sorry but I am having a hard time understating the following "In general I like RAM ( Roger Modjeski ) for hyper strict grading of current production tubes. His many many variable computerized testing system washes some 90% of certain tubes out. His Ultra low noise 6922 are what I use in his RM-9. we lost the genius, RIP but RAM lives on. I also use an E Bloc EL-34 of his…a Phat EL-34 for sure."

English is not my first language, I use it only for technical reasons. :)

Is Roger Modjeski still in business and can buy his tubes?

I would certainly love to lower the noise in the Steelhead while removing a little of the harshness while giving it a little more definition open and deepen the soundstage. 

Do you have a site for Brent Jesse?

VTS site is good! I will try to reach him.

As for seats it depends on the pieces being played, but center E-Q is a good average but leaning towards F-M. 

astolfor's avatar
astolfor
317 posts
 

@drbond thank you for the reply. I have my DAC/Streamer connected to it as well as my tone arms. 

After some tube rolling I would like to do some upgrades as a few here have suggested. I do not want to spend a lot of money upgrading the Steelhead but lowering the noise floor (?) and getting a little deeper and wider soundstage and definition would be great.

 

More to discover