Schiit Saga vs Freya

[Abtr]

The less electronics in the analogue audio signal path the better. I don't need the gain of the Freya, just the passive resistor based volume control plus active low impedance buffer of the Saga. And in my system the Saga sounds (much) better than any other preamp I've tried so far..

 

As did Firedog (with the Freya's pair of gain stage tubes), I will upgrade the Saga's single (NOS Sovtek 6SN7GT/6H8C) buffer stage tube with a brand new Tung-Sol 6SN7GTB that should last ~10.000 hours..

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... Abtr, how much do you expect to hear the differences between the factory and the Tung-Sol? I know everyone points to a little more this, a bit of that - but if you were to give a % (say, 5%) what would it be you think?

Well, the stock tube I received from Schiit with the Saga, produced some crackling sounds and noise (in both channels) which generally means the tube is at the end of its life.. I replaced it with another Sovtek 6SN7GT NOS tube and the problem was solved. The Saga sounds brillant. I don't expect the Tung-Sol to sound better (that's 0% improvement), but NOS tubes appear to be less than 100% reliable. Hence, the new Tung-Sol..

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Actually, I'd expect more reliability with NOS tubes than new ones. :-) I've compared 6SN7s for years now and I always come back the the GE 6SN7GTB. A solid, rich and balanced presentation. You can get matched pairs for about the same as a premium new 6SN7.

Well, the new Tung-sol tube certainly sounds different from the NOS Sovtek tube you get standard with the Saga. I think The Tung-sol sounds better..

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My Freya came with tubes from the Novosibirsk factory. They are 6H8C. From what I've been told by a vendor, they are old military tubes.

Yes, that's also the stock Saga tube. 6H8C and the number 8510 are printed on the tube. The number 8601 is printed on the base. They are (NOS) Sovtek 6SN7GT tubes produced in the Novosibirsk factory (6H8C is the Russian designation for a 6SN7). Not sure if they are military tubes but they might be. Apparently these tubes are used in many currently produced tube amplifiers.

 

My stock Saga tube was producing periodic crackling sounds and noise, maybe it got damaged from some shock or dropping, after all it's a NOS tube.. I found a replacement Sovtek 6SN7GT for € 13 that has 6H8C and the number 8602 printed on the tube and 0 and 1 printed on the base. It sounds just fine, but I prefer the new Tung-sol 6SN7GTB.

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I'm not that crazy about the Treasure/Psvane 6SN7. It's a nice tube, and it certainly depends on your system. A lot of people love them. They do have a big, open sound, similar to the Mullard ECC32. I guess I should try mine again. :-) But the quality control is so-so and they can be noisy and microphonic, the last thing you want in a preamp. I find that the GE 6SN7GTBs do everything very well for a reasonable price. Production was very consistent, they'll tolerate high voltages, microphonics are extremely low and they're generally tough as nails. NOS or very strong matched pairs go for $60 or less.

Hi Zackthedog. Do you mean the early 1960s GE 6SN7GTB: GE 6SN7GTB - matched pair? What about this one: GE 6SN7GTb: Vacuum Tubes & NOS Tubes | Tubes Unlimited? And are you familiar with the GE 6SN7WGTA (1968-1970): 6SN7WGTA General Electric - Tubes: Odd Ball Tubeampdoctor Store? Thanks.

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I mean the first pair, yes. Better to avoid the later, wafer-base version, though they would probably be okay in a pinch. The 6SN7GTA is a different animal. They look exactly the same but believe it or not they sound a bit different, with a more prominent midrange and little less open on the high end. They also have a lower maximum voltage rating. That's a nice mil-spec model there, never seen those. But apart from the brown base I doubt it's very different from the stock versions, and I wouldn't pay that sort of premium for them.

Thanks! I ordered an early 1960s G.E. 6SN7GTB for the Saga. Should be here this week.

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I hope you like it. :-) Let us know what you think.

I promise I will do that.

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Does the SAGA use a Hybrid tube stage with transistor acting as a CCS? I think that I read that somewhere. ...

Yes. I think that's implied here: Saga ..

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... the Treasure/Psvane 6SN7s tend to have a larger base than NOS tubes. I see that the Freya has its tube sockets recessed below the cover, and the tube base must fit into the hole in the cover. This could be a problem with the Treasure/Psvane tubes, but I couldn't say for sure. ...

The Psvane CV181-T mkII/6SN7 does fit in the Saga (just). The glass bottle almost touches the cover.

[Abtr]

The Psvane CV181-T mkII/6SN7 does fit in the Saga (just). The glass bottle almost touches the cover.

That's good to know, thank you.

Oh, and the new Psvane has a very pleasant sound; well-balanced/coherent, open and dynamical. Bass, highs, texture and details are great. The Tung-sol 6SN7GTB (new/reissue) is also quite open sounding but sounds relatively harsh. I think the Psvane is in a different league soundwise..

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Yes, they can be quite nice depending on your system. ...

Well, the system basically is the Schiit Saga.

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Two tuby newby questons:

 

1) Is the Psvane your referring to the same product as a "Shuguang Treasure CV181-Z"?

 

2) #1 (rather the same or two different products) is a different product altogether than a "Sophia Electric 6SN7" correct?

Well, I'm a tube newbie myself. Anyway, the Psvane is not the exact same tube as the Shuguang, the Psvane may be seen as the most recent version of this type of 6SN7 valve. It also seems that Psvane is a kind of sub-division of Shunguang or vice versa.. The Sophia Electric may be yet another version of the same tube, I don't know..

 

I received my Saga yesterday and with the factory tube my first impressions fall into these sorts of thoughts:

 

"who stole my subwoofer?"

"what happened to my tweeters?"

"why do most recordings sound metallic, brassy, distant, etc.?"

"why do some (but not all) voices sound a hair more "natural", and why do brass instruments (trumpet, etc.) also seem to benefit sometimes from this metallic coloration?"

 

I am sure none of this surprises you guys...

Are you sure you are listening to the Saga in *active* mode? Depending on your power amp and/or sub, the Saga's passive mode may sound a bit lifeless. In active mode (indicated by the most right LED) I think the Saga sounds already very good with a (standard) Sovtek tube, maybe you must give it some more time.. In my system I prefer the Schiit Saga over a number of other good preamps..

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Yes - I am mostly running it using the tube (active). Actually, in either mode (active or passive) the low and high's are rolled off compared to when I run my DAC directly into my (integrated) amp - I am hoping it is a break in thing...

What DAC do you use? And frequency roll off you can measure?

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... Actually, in either mode (active or passive) the low and high's are rolled off compared to when I run my DAC directly into my (integrated) amp - I am hoping it is a break in thing...

Are you running the Saga into an integrated amp? That makes no sense. What integrated amp?

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My experiences (and thus, my opinion) tell me that Chinese tubes are particularly junk. It's not that they sound bad, but their build quality ranges from mediocre to unbelievably bad. For instance, how about tubes with phenolic-bases (such as octal and 5-pin (2 fat pins, 3 skinny ones) that have the glass envelopes literally come out of their phenolic bases (and break wires) when one tries to remove the tube from it's socket! Or, with tubes have a plate cap, having the tube cap come off when one tries to remove the plate lead. The cap comes off stuck inside the plate lead connector so that it has to be dug out with a knife blade, leaving only a short stub of useless wire sticking through the glass on top of the tube! I've seen the bases separate on Chinese octal-based tubes such as 6SN7s, and both the bases and plate caps come off on 807s (an 30 MHz spec'd 6L6 used throughout the 2nd WW, and up into the 1950's for military transmitters and more recently used as an audio output tube).

 

 

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Well, I can assure you that the base of the Psvane CV181-T mkII is firmly attached to the valve.

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What...I thought everybody does that...

 

Seriously, the Saga is part of an upgrade to my "computer speaker" setup that I actually listen to more than anything else because I work so much on the computer:

 

(Jriver or Roon) > Ifi iDSD > Emotiva a-100 (a cheap Brio clone) > Legacy Audio Studio HD's & REL sub

 

My plan (such as it is - I spend most of my time thinking about world domination ) is to upgrade the amp and so I purchased this Saga and I will pair it up with some similar budget-but-hi-fi amp like perhaps Schiit's soon to be sold class A/B 100/200 watt (can't remember the name) or perhaps a Parasound A23, etc.

 

So right now the Saga is in between the iFi and the Emotiva - it is the only thing new/changed (that, and an additional short run of Blue Jeans "LC-1 Low Capacitance Audio Cable"). Well, I have the volume control on the a-100 (which I assume is cheap potentiometer commensurate with the rest of the unit) turned all the way up - which I believe (correct me if I am wrong) gets it out of the way (if not out of the circuit).

I haven't a clue as to what might be going wrong here. What's the input impedance of the Emotiva a-100?

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Only thing the manual says is:

 

"Input sensitivity (for full output): 600 mV (8 ohm load)"

 

Saga's specs read:

 

"Output Impedance: 180 ohms"

 

I can't find the impedance (RCA out) listed for the Ifi iDSD...

 

So a mismatch you think?

Not very likely, unless the input impedance of the Emotiva is below 2k Ohm. Maybe you created a ground loop somehow..

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Ok, just in the past 30 minutes my Tung-Sol 6SN7GTB (these are "new stock" - recently manufactured unless I am mistaken) was delivered via Fed-Ex. I ordered these from Upscale Audio, and according to the side of the box they have done some measurements ("T1" & "T2" - no idea what they mean) and graded them (these are "A") and they checked the box "burn in" so I assume they have some time on them.

 

In any case, my subwoofer and tweeters have been returned (I am going to catch the SOB who "borrowed" them ) and a much more neutral (can't hear any metal harshness/veil) presentation is coming from my speakers.

 

UPDATE: oh boy - listening to Kurt Ellings "Bonita Cuba" (24/96) and I am resisting turning it up to rock concert level's...perhaps I am hearing tube magic...nice

 

Much much better...

Yes, I also found the new Tung-sol sounding better than the factory NOS Sovtek tube. And the 6SN7 is a double triode tube. I guess T1 stands for the first triode and T2 for the second. In the Saga the 6SN7 isn't used for amplification/gain so the two triodes being precisely 'matched' is not that important. Anyway, good to hear your problem is solved.

[Abtr]

Well, er, I wouldn't say that. ;-) If you want the output impedance of both channels to match precisely, I think matched sections would matter.

Hi Zackthedog. As you know, the electrical characteristics of a vacuum tube are commonly described by three variables: voltage gain (Mu), transconductance (Gm) and plate resistance (Rp). In the case of triodes these are related: Mu = Gm x Rp. Mu and Rp are most important, where Rp directly affects output impedance. However, I understand that Mu and Rp are very difficult to measure and most/all vendors measure only Gm. With two triodes matched only for Gm (Mu/Rp), there is no assurance whatsoever that Mu and Rp will match. It seems to me this practice of matching tubes (triodes) is questionable and largely a marketing ploy..

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I think you have a point, though I don't agree that matching sections is a "ploy". In a phase-splitter, a poorly-matched dual triode is going to affect the signal balance. The very least you can do is match the halves for Gm, even if further testing would involve more time and effort. In a cathode-follower, which I assume is being used here, it's probably less critical, but I'd still want to know that the two sections were performing somewhat equally.

 

ETA: Here's a good overview of the "matching" issue that sums up the issue pretty well. It addresses your concerns about the limits of tube matching.

 

TubeSound » Blog Archive » Tube Matching with a Tube Tester

Thanks for the link. Do you think matching Gm of the two sections of a *single* dual triode tube is more likely to indicate matched Mu and Rp, than would matching Gm of a *pair* of tubes?

 

BTW, As of yet I didn't receive the G.E. 6SN7GTB (1960s vintage). Should be here by Monday. I did try a new Shuguang Treasure CV181-Z in the Saga and it sounds different from its cousin, the Psvane CV181-T mkII. A bit more lush perhaps. I like it.

[Abtr]

Well, that's an interesting question. The original Williamson amplfier design used four 6J5s instead of two 6SN7s. (the 6J5 is equal to one half of a 6SN7). I'm not sure of the reason for this, but one advantage would be that you could carefully select four matching 6J5s rather than search through batches of 6SN7s for well-matched halves, if you see what I mean. So, for instance, if the Saga used two 6J5s instead of one 6SN7, you could select your 6J5s for a better match. :-)

 

Which raises another interesting point: You *could* replace the single 6SN7 with a dual 6J5 adapter (you can get these on eBay) and use two 6J5s--a lovely tube, BTW. You'd probably need a socket extender (also available on eBay) because of the recessed socket. Just another tube-swapping option to drive you nuts. :-)

Well, I was thinking that because the dual triodes of (e.g.) a single 6SN7 tube are obviously of the same make/series/date, matching Gm may yield a relatively high probability that other variables (Mu and Pd) are also matched, whereas selecting two different tubes for matching Gm may have a lower probability of being matched for Mu and Pd (where Gm = Mu/Pd).. Just a thought..

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Thanks! I ordered an early 1960s G.E. 6SN7GTB for the Saga. Should be here this week.

I hope you like it. :-) Let us know what you think.

Sorry for the (slight) delay. I received the GE 6SN7GTB (1962 vintage) tube for the Saga. To be precise: a GE 6SN7GTB (EC33) red label, like this one:

 

.........................................

 

Gm = 2400 (a dimensionless number) for each triode section, and in my current system it's the best tube I've tried; better than the Psvane and Shuguang.

 

Here's my personal (preliminary) Saga tube review:

 

- Sovtek 6SN7GT (factory 1970-80 vintage): Nice but relatively dull

- Tung-sol 6SN7GTB (new): Relatively harsh but quite open sounding

- Psvane CV181-T mkII (new): Well-balanced/coherent, open and dynamical

- Shuguang Treasure CV181-Z (new): Like the Psvane, well-balanced/coherent, open and dynamical, but a bit more lush sounding

- GE 6SN7GTB red label (1962 vintage): Best I tried so far, very dynamical, very well-balanced, very coherent, very good bass and mids and smooth highs

 

The GE tube really rocks, and I don't think this is an artifact of my system (although it does seem to tame the KEF's highs a bit). It sounds very natural and authoritative in every frequency range and genre. Also, of the tubes I tried, it sounds the most different from the Saga's 'passive mode'. Wow!

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Told ya! ;-)

 

Seriously, I'm glad you like it. I find that they convey a lot of energy without sacrificing balance across the range. That 2400 sounds like a Hickok measurement and is a solid NOS reading. Should last you a long time.

A really amazing tube! I highly recommend it for the Schiit Saga. The Saga with this tube sounds better than anything I've tried in terms of pre-amplification (passive or solid state or other tubes) in my current (and previous) system(s) so far. There may exist better triodes, but the performance of this GE takes my current system to a level of realism in sound reproduction that I actually didn't think was possible. Thanks again!

 

On the other hand, this result makes me wonder whether solid state (pre)amplifier designs are somehow fundamentally 'flawed', and if so, and if (currently) the best audio tubes are NOS tubes, then there may be a supply problem in the (near) future!? I'm interested to hear experiences from Freya users who compared the JFETT buffer to (NOS) tubes..

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Where did you buy them?

GE 6SN7GTB - matched pair

 

They appear to be out of stock And the picture doesn't show the red labels I received..

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Are the two Schiit preamps truly Tube driven or just a buffer like the older Peachtree stuff?

The Saga is a passive resistor-based volume control + an active tube buffer..