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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
ericsch
753 posts
 
I would not buy tubes on Ebay unless I received a strong recommendation from someone on this forum or another similar. I have purchased tubes from Andy at Vintage Tube Services and Upscale Audio with excellent results. Brent Jesse is also highly recommended. I have no experience with the Freya.   
xenolith's avatar
xenolith
134 posts
 
Have purchased new production and NOS tubes from most of the well known vendors.  Best results have been from Brent Jessee Recording.  While a bit more expensive than most/all other vendors, the testing and matching service he provides is, I believe, the most extensive available.  
petg60
1,486 posts
 
Nos, you are not hunting the holy grail with them.
Hit and miss but at least you will get the experience. A good vendor will always be helpful whatever the outcome. 
Something i always say is that modern equipment are designed with modern production tubes in mind, so if you like what you are hearing then go with same tube and if you have the itch for nos then go with older production ones but from same manufacturer.

G

ghosthouse's avatar
ghosthouse
4,312 posts
 
Hello Glen -
I own the first gen Freya so am speaking from that experience. Hope it is relevant.

-Have you confirmed a proper impedance match between pre and amp?

-My next thought is be patient. 75 hours might be enough for the tubes but maybe not for the Freya to settle and "burn-in" (as recently controversial as burn-in time has become). Regardless that, my listening enjoyment benefits from allowing new gear adequate burn-in and settling time.

- It’s not unusual for installation of a new piece of gear to require "re-tuning the system" entailing (at least) adjustments to speaker placement. Knowing the rest of your gear and cabling would be helpful to members here. Maybe the Freya is just letting you hear a wider frequency range. Can you move speakers closer to the wall behind them? With some speaker types this can improve lower mid range and bass.

-I’m not sure there’s a way to accurately predict what impact tube rolling is going to have on your system sound to your ears. You might get some helpful advice from the likes of Jim McShane, Brent Jessee or Upscale Audio. Some vendors will allow returns on noisy tubes or if you just don’t like the overall sound (e.g., Brent Jessee but you’ll pay up front for the right to return, as I recall).

- I’ve run probably half a dozen different tube brands (NOS and new production) in the Freya. Some VERY inexpensive ($10/tube) Russian 6N8S that used to be a stock offering from Schiit did seem bright and harsh at the start but eventually settled down and warmed up tone-wise. Still not my favorites but did get better than they were out of the box.  (Right now listening with NOS RCAs in gain and current production Tung-Sols in driver).

-A bright top end (one that makes strings tough on the ears) is a personal bug a boo and something I battled for a long time given metal dome tweeters on the Totem Forests I have. This had nothing to do with the Freya.  Thin mids and bass, however, were never a problem even with brand new el-cheapo tubes.  Now, issues with high frequencies are all things of the past having made adjustments to speaker position, changes to cabling (including choices between upper vs lower binding posts vs which diagonal connection pattern) and installing an Aquarius power conditioner.

Hope this will give you some ideas to explore in addition to tube rolling.


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