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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
tomic601's avatar
tomic601
12,865 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
396 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
396 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. . . 

drbond
396 posts
 

@astolfor 

Well, the output buffer tube selection is quite readily evident:  

Philips 5687 JAN gives a brighter slightly more detailed presentation, which is also more grainy (not smooth)

Tung Sol NOS 5687 gives a smoother presentation, which seemed more musical and enjoyable to listen to in my system. 

It would be interesting to hear if anyone has compared the 7044 tubes with the 5687 in the buffer stage. . .

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