2. amps-preamps
  3. 1345270360

tube preamp in SS receiver loop

From noob, a very basic and probably very stupid question that I can't seem to find answered elsewhere:

I want to experiment with inexpensive tube sound to augment a modest solid state receiver. I have looked at tube buffers marketed expressly for that purpose, that is, for those who want to insert tube "warmth," which I know is a kind of distortion that many hate, into solid state setups (e.g., the Grant Fidelity B-283). But I would like a tube phono stage as well. So I am looking at a tube preamp with one line level input and one RIAA input. But I would like to use it on all the line level sources coming through the receiver (tuner, CD, computer, ipod, whatever), so it would go between the pre out and main in on the receiver, or else in the tape loop. In other words, the line level signal would go through the SS preamp, then the tubed one (the turntable would of course go straight into the tube preamp). Is it kosher to use a preamp in this way? That is, as a buffer stage that comes after the solid state receiver's preamp circuit? In other words, can you use a variable gain preamp as a (passive?) buffer? Clearly I have no idea what I'm talking about. Thanks for any thoughts you may have.
vesuvio
bob_anderson
1 posts
 
I have a Linn, Majik DSM which is an excellent digital music player, (integrated), with all components connected to use it's volume and switching, (and great DAC), and then fed via pre-out to a MasterSound 300BPSE which is also an excellent, Italian integrated which I am only using the Line-in so it's role is strickly amp.

The sound is pure and magical. No coloring but the staging and separation is the best my aging ears have ever heard.

Higher end than what your testing but an excellent higher mid-range configuration that simply delivers beautiful sound, (and the amp is only 24 watt)!

My speakers are custom built, (based on SEAS Exotics), and at 91db efficiency, let me hear if anything is amiss and so far, the only disappointment has been some the tubes I have purchased, but then that has also allowed me to find a combination that has had me in tears of joy.

Your idea works and delivers beautiful sound.

Cheers

Bob
firedog55
4 posts
 
Grant Audio used to have the P-307, which is like the MkII 283 but has a phono input. http://shop.grantfidelity.com/Grant-Fidelity-P-307-Tube-Phono-Pre-amp.html

It's now unavailable but you should write and ask them about it.

You can get basically the same thing but without Grant branding and quality control at:
http://audio4lessonline.com/Yaqin_MS_22B_Tube_Phono_Stage_Amplifier.html
manoterror
216 posts
 
I have had great success with 2 Grant Fidelity tube buffers. The smaller 283 in my office system, and the MKII 283 in my main system. I've updated the tubes to cryo-treated, and use a decent power cable. I have them between the DAC and the Preamp.

I only use them between the digital sources, not analog, and the preamp. After all, that is what needs the most help. It works wonderfully, and only cost $350 with upgraded tubes for the MKII.

Another inexpensive option if you want to go preamp, is the Jolida JD5T. Tube preamp, with remote, for $425 new.

Enjoy,
Mot
vesuvio OP
5 posts
 
I am very grateful for all of your thoughtful responses, and am learning a lot! I have been away from all this for a few weeks due to a frantic new job with ungodly deadlines, and before reading some of the more recent posts here -- in fact not realizing they WERE here -- I acted on the Yaqin ms12b tube phono stage and line preamp, which arrived the other day. If it doesn't work for me, it can go on sale. I would like to have the money to do better than trying to cobble it together with my modest vintage SS receiver, but maybe that will come with time.

I've just begun to experiment (a wonderful way of not worrying about work!). What I have discovered: If I plug the Yaqin directly into my receiver's PRE-OUT MAIN-IN loop, all the receiver's tone and volume controls are disabled for the phono, which of course goes directly from the RIAA input on the Yaqin preamp to the solid state MAIN IN. Tone and volume do work for other sources, I guess because they go through the SS preamp before going into the Yaqin, and I do have the Yaqin volume control.

If I plug the receiver's TAPE OUT into the Yaqin LINE IN and the Yaqin output into the receiver's MAIN IN, resulting in a TAPE OUT-MAIN IN loop, the receiver's tone controls are bypassed for all sources and the receiver seems to act as a source selector without modifying the signal, so that might be the purest solution. But I may still need tone controls at this point.

So far, with the Yaqin going directly into the power amp--without the use of tone controls and the ability to temper the treble--I find it harsh and tinny, much more so than the SS receiver on its own--which I was trying to mellow and soften. (I am not yet a purist!) Of course, I still have new stock Chinese tubes in it, which are not supposed to be all that great.

On the other hand, if I put the Yaqin into the Marantz TAPE-IN TAP-OUT loop, where I have the advantage of the receiver's tone and volume controls, the sound is more pleasing--still not sure how much better it is than the plain ol' Marantz is, but maybe tube rolling, which I have never tried, might be the next step.

This is all quite confusing to me, and one day I may bite the bullet and go for an integrated tube amp. But in the meantime, what about just leaving the tube pre-amp in the tape loop, with access to the receiver's tone and volume controls? At least for now? Followed with better tubes fro the Yaqin.

Or can anyone think of a better configuration? Thanks, all, for sharing your knowledge and expertise.
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