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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
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.

 

tomic601's avatar
tomic601
12,911 posts
 

certainly, always try to help a fellow addict..ha.

tubeaudiostore is RAM and Brent Jesse recording supply, should get you to his site. both have decent websites. Based on seat selection, i would suggest Amperex or Telefunken, but the Steelhead owners will have super valuable input. never a need to apologize, i worked w suppliers and customers globewide and in orbit…language is always a challenge and opportunity….

my best to you

Jim

drbond
419 posts
 

@astolfor 

The Manley Steelhead is an excellent component, as I've had it in my system for 10+ years; however, as a buffer stage, I think it's best suited for a mid-priced audiophile system.  As a phono stage, I currently think it sounds very good in my higher-priced system, but I have yet to compare it to other phono stages.  

While tube rolling does affect some minor sonic aspects of the component, the resolution is still limited by the design of the device itself.  After doing so myself, I wouldn't spend $400 for a pair of 6922 on the Steelhead, as the $100 pair seems to sound just as good. 

. . . and the tubes can be had from many sites.  If you're in Europe, the Tube Amp Doctor seemed to have good prices/products.  In the US, yes, there are many sites, but if you're looking for Brent Jesse, and can't find him, that's because it's spelled Brent Jessee.

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drbond
419 posts
 

@astolfor 

I always like to compare the sonic differences of small tweaks, and switching out the tubes in my Steelhead as a phono stage should be a fun activity over the next month or two. . . I'll do some tube rolling, and get back to you in this forum in a month or two. . .I only have the Tung Sol and Philips in the 5687; I have about 4-6 types of the 6922. . . 

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