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Tube Rolling Woes

I recently took delivery of my first tube preamp. Schiit Freya+. It came with new production Tung Sol 6SN7GTBs. I'm running fully balanced from my source components right through to the power amp. My first impression was wow! What an improved soundstage with width and a 3D quality that I've read about. What surprised me is how quiet the system is. I had expected tubes to be noisy. But the Freya+ running with the new Tung Sols is dead quiet. The openness and air in the presentation is tremendous. However, from a voicing perspective, the top end is bright, and the mids and bass are very thin. I have about 75 hours on the system. Ive read and listened to almost every review on this model and no one has complained about the tonal balance. I left an email with Schiit just to make sure that I haven't done something wrong, but haven't heard back yet. 

I thought I'd experiment with some NOS and used vintage tubes. I've purchased from established, well respected vendors as well as folks with excellent feedback ratings on eBay. Of the 8 tubes I've purchased - claimed as tested matched quads (1) or pairs (2) - all but 2 have been either prohibitively noisy, or just didn't pass a clean signal. From my (admittedly small) sample, there has been no quality differences between the well-respected companies selling NOS tubes vs. people selling used stuff on eBay. The good tubes I've received were used tubes (RCA) sold by an eBay vendor. 

So I'm running out of patience. If I go with new production tubes that a vendor will have tested, matched and stand behind the quality, how do I know what to buy? Note that this is a $900 preamp. So, there are limits to what is practical in terms of price point. I can't justify spending more than $200 on replacement tubes. My concern is that even if I spend this kind of money, how do I know what the results will be? 

Any advice is appreciated.

Glen 

128x128spacecadet65
oldhvymec
5,101 posts
 
That is the trade off, sometimes. Tone control through valves is tough and it takes someone that knows what they are doing. Tone control circuits were eliminated because of cost AND the noise they can add to the signal.

It is best if you plan to keep the unit, speak, listen and spend. Don't spend, speak and NOT listen.. I do the latter all the time.. Not so much anymore.. I find my pockets stay a little fuller and personally I stay a little calmer.. :-)

Talk the Brent Jesse and tell him that you have and what you want to do. SEE what it cost... That is what an OLD Mechanic would do...

Yes the little Freya + is a neat little unit. It is pretty transparent too. You are getting more than what you pay for MOST of the time. They are a good deal. NOT GREAT, NOT Perfect. But good and better than any at that price range... IMHO I like the look and weight too.. Heavy...
millercarbon's avatar
millercarbon
12,531 posts
 
Ghosthouse nailed it. Audiophiles love to talk about expectation bias. Which is largely fake, by the way. Hardly anyone ever talks about recency bias, which seems to be hard-wired into our brains. You made a change, its not perfect, you assume all the imperfections are due to the change. It is equally likely to have had imperfections there all along, only you had a combination of components and setup that had kept you in the dark, so to speak. The new component in this case is not creating them but merely revealing them. What ghosthouse said is correct. 

That's what I think. Give it time. Tube rolling is not for fine tuning magic, not patching over shortcomings. 
spacecadet65's avatar
spacecadet65 OP
58 posts
 
First to everyone: THANK YOU for the great advice! Some have asked about what the rest of the system is:

Freya+
PS Audio Stellar S300 Power Amp
ifi NEO iDSD DAC
Denon Pro DN-500BD MKII DVD
APC H20 Power Conditioner
Bluejeans Cables throughout
Triangle BR03 speakers (waiting for Tekton Impact Monitors on order)

I completely get the risk of eBay. As usual, the cheap way doesn't work. 

Ghost: All great feedback. I'll try the patience thing - I'm going to put the OEM tubs back in and use them for a few weeks, leaving the pre on 24/7 and see how it goes. I listened to an Upscale Audio YouTube video and he was emphatic about all tubes - new or old need a minimum of 200 hrs. before evaluation is meaningful. I'll mess around with the speaker placement and see if that helps. I've played with the toe-in and it helped a bit. More work needs to be done there. 

OldHvyMec: Always good advice. So far, I did a lot of research, spent then listened... So I'm listening to you all now and appreciate the feedback. I'll let the OEM tubes settle in for a few hundred hours and see where I stand at that point. If the voicing issue is still there, Checking in with Brent, McShane, and Upscale and see what the options are. 

Miller: I've been lurking a bit and have always appreciated your comments. Thanks for affirming what others have said on this one. There's no doubt that my little system has all manner of flaws, and the Freya has likely uncovered some of them. With 2 kids in college, this is the budget I'm dealing with. It's a good reminder that tubes aren't effective tone controls.  As an aside, I have a pair of powered Tannoy nearfield studio monitors that I use in a small room system. While they are revealing, there is something in the upper midrange that goes right through me. So I purchased a Schiit Loki EQ (a very very poor man's Cello Audio Pallette) and learned that an EQ won't fix a speaker voicing that you hate...

Thanks All!
djspinner's avatar
djspinner
60 posts
 
Are you experiencing similar issues (top end is bright, and the mids and bass are very thin) in the passive and/or buffer modes as you are in tube mode?
oldhvymec
5,101 posts
 
The voicing that was going right through you is most likely room treatment.. Un kind or bloated upper MIDS, mercy they can wear you out..
Not to mention blistering LOWER highs.  MC has a point too. 70 hours is pretty low hours for anything to get RIGHT.. Little room treatment, maybe change the placement a bit.. Settling, you getting use to it a bit..

Spend no more and collect some good data.. Seems like a good plan to me.. You'll get it.. Man oh man kids in collage. I just had one go BACK for the second time. God bless his learning mind.. Hope he fattens' his wallet at the same time along with a brain blessing.. LOL a Twofer..

Regards
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