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    VTA-70 and SP-10 impressions

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    dougmon

    Posts : 65
    Join date : 2013-11-04
    Age : 60

    VTA-70 and SP-10 impressions

    Post by dougmon on Mon Jan 20, 2014 1:34 pm


    Early last year, I picked up two new pieces of equipment: a VTA-70 and an SP-10 preamp.

    I've owned tube amps before: a Conrad-Johnson MV-55, a Cary SLI-80, and a stock Dynaco ST-70. At one point, I decided that I would never mess with tubes again (don't ask, I don't remember why), but that proved to be the wrong decision. So at that point I picked up the ST-70, put new input jacks and speaker outputs on, and used it for the next several years with a passive front end.

    After a while, the ST-70 started to show sign of wear; either some of the soldering I did was not that great or...well, who knows? At this point, it had been many years since I picked up the soldering iron, so I decided to get a pre-made amp, and decided on a VTA-70. And it sounded great; but I started to wonder what it would sound like with an active preamp. So I picked up an SP-10 preamp.

    I should note here that my VTA-70 has the cap upgrades, and the SP-10 has Auricaps in it. So neither of them are stock. And, as long as I'm disclosing stuff...I did a little tube rolling on the VTA-70. I know that Bob Latino suggests that no tube-rolling be done before running the VTA-70 in for about 200 hours, but also, I have to admit that after about 100 hours, I realized that the Valve Art EL34s that shipped with the amp were not to my taste. So I put in some SED =C= 6L6GCs. I also pulled the "Realistic Lifetime" rectifier (probably a Matsushita) from my stock Dynaco and put it in the VTA-70.

    Here's my first impression, from when I was using the passive front end: the VTA-70 is not only different than the stock ST-70, but different from any other tube amp I've ever had. Both of the other tube amps I've owned imposed much of their own character on every recording. The VTA-70 gives a beautiful tubey character to everything, but there is no mistaking one recording by a given artist for another by that same artist. Yet everything is very listenable; once the power tubes settled down a little, there was no harshness in any recording I listened to; even some recordings that were mixed very harshly settled down a little. Note: by 'tubey character', I don't mean lush and diffuse; I mean that there was none of the artificial treble and bass emphasis that I've come to associate with much solid-state amplification (even some very expensive solid-state).

    Since I was so happy with the VTA-70, I thought it would be nice to try a VTA preamp. I chose the SP-10 because it had the features that I needed: a balance control and a tape out for a headphone amp. The SP-10 is the first active preamp I've had in about 10 years. I don't have a lot of audiophile vocabulary for the difference it made; mostly, there is more weight and presence to the music. And though the passive front end was a little more detailed in an odd way, the music now has a coherence that it didn't have before. Rock recordings _really_ rock now, and I keep having those "wow, that was great!" kind of moments. There are also things I'm hearing that I don't think heard really well before, like Robert Cray's beautiful guitar tone, or how great the Beatles' harmony vocals really were.

    For me, the VTA-70/SP-10 combination passes the most important tests of a stereo system: I don't get fatigued after listening for three or four hours, I don't have to give up features I want for a great sound, and it does all types of music well.

    If I'm unhappy about anything, it's that I didn't get a kit and build the VTA-70 myself. But that's ok; I have a stock ST-70 that I'll be upgrading with the tubes4hifi octal driver board once I feel I've done enough soldering practice. I'm also a little worried that after a while, I'll get the uncontrollable urge to check the SP-14.  Very Happy 

    I hope this post is useful to someone. I would not hesitate to recommend either of these components to anyone who likes to listen to music.

    Laminarman

    Posts : 110
    Join date : 2009-12-30

    Re: VTA-70 and SP-10 impressions

    Post by Laminarman on Wed Jan 22, 2014 10:48 pm

    Very nice post, thanks for the information. I'm still burning in my VTA 70 and I can't believe that it made my Tannoy speakers into something they never were before, they just sound wonderful. It's such a cool looking piece too (at least I think, I know others differ in their opinions.)

    dougmon

    Posts : 65
    Join date : 2013-11-04
    Age : 60

    Re: VTA-70 and SP-10 impressions

    Post by dougmon on Thu Jan 23, 2014 1:56 pm

    Laminarman wrote:Very nice post, thanks for the information. I'm still burning in my VTA 70 and I can't believe that it made my Tannoy speakers into something they never were before, they just sound wonderful.  It's such a cool looking piece too (at least I think, I know others differ in their opinions.)  

    Well, I'm glad you got something out of it.

    I like the looks too. They're not fancy, but very functional.

    One thing I don't think I stated explicitly was how responsive the whole system was to tube-rolling. At one point, I tried the Tung-Sol 6L6Gs; the difference between those and the SED =C= 6L6GCs is amazing, even though they're supposed to be very much alike internally.

    Truth to tell, I did expect something close to my old stock ST-70 when I got the VTA-70 -- but I think I got a lot more, even before I put the SP-10 into the mix.

    Laminarman

    Posts : 110
    Join date : 2009-12-30

    Re: VTA-70 and SP-10 impressions

    Post by Laminarman on Thu Jan 23, 2014 3:10 pm

    After endless hours of thought of what my future needs would be and where I wanted to go with this, I ended up ordering an SP14, so I can't wait to see what that does. The goal, in less than a year, is to have my own separate two channel "oasis" to go to and escape. After the SP14 and sources, I start the long, painfully expensive experience of shopping for speakers. If I'm unlucky I suppose I'll venture into tube rolling too : )

    sKiZo

    Posts : 1310
    Join date : 2013-04-01
    Location : Michigan USA

    Re: VTA-70 and SP-10 impressions

    Post by sKiZo on Thu Jan 23, 2014 6:12 pm

    What ... you're not gonna build your own speakers?

    Harumph.  Wink 

    Don't forget hardscaping ... prepping the room acoustics is a BIG part of the experience. Even something as simple as padding the primary reflection points can make or break the results.



    dougmon

    Posts : 65
    Join date : 2013-11-04
    Age : 60

    Re: VTA-70 and SP-10 impressions

    Post by dougmon on Thu Jan 23, 2014 6:26 pm

    Laminarman wrote:After endless hours of thought of what my future needs would be and where I wanted to go with this, I ended up ordering an SP14, so I can't wait to see what that does.  The goal, in less than a year, is to have my own separate two channel "oasis" to go to and escape.  After the SP14 and sources, I start the long, painfully expensive experience of shopping for speakers.  If I'm unlucky I suppose I'll venture into tube rolling too : )

    Well, if you can avoid tube rolling, good for you. Myself, I'm always wanting to roll off the treble just a little (slight case of tinnitus, so less treble helps). Getting some different tubes is a good way to do this. (I have heard the advice "Don't use tubes as tone controls", to which my answer is "Why not?").

    Speakers are difficult. Don't take advice. Just go listen. Um...yeah, don't take advice _unless_ the advice is "just go listen". I got my speakers on the basis of hearing them in the shop about six times and then being able to listen to them in my home for an afternoon.

    In any case, good luck with it all. I'd certainly be interested in reading your impressions of the SP14.

    Laminarman

    Posts : 110
    Join date : 2009-12-30

    Re: VTA-70 and SP-10 impressions

    Post by Laminarman on Thu Jan 23, 2014 8:40 pm

    Thanks Skizo and Dougmon. No Skiz', no speaker build here. I just can't see me making something that sounds as good as what I've heard, and I suffer from a fault with woodworking: I want to get DONE by the time I start sanding. I'd rather jackhammer a molar out instead of sand wood, stain, finish...etc. Just not a strength of mine that woodworking thing. This system will go into our basement which is being finished, so I'll have a chance to control acoustics to some extent from the get go. Assuming I get the SP14 built properly I'll post my impressions. I'm rather nervous since I've heard it doesn't have step by step like Bob's 70 amp, but Roy assured me since my amp build went well first time I'm up to the task. We'll see.

    Laminarman

    Posts : 110
    Join date : 2009-12-30

    Re: VTA-70 and SP-10 impressions

    Post by Laminarman on Thu Jan 23, 2014 10:29 pm

    dougmon, you mentioned the Beatles. By chance you listen to the highly touted mono recordings? I haven't but I've heard they're spectacular on valve amplifiers. I'm tempted to buy the collection because I can lose myself in them. If you read the Amazon reviews they're across the board pretty satisfying to most folks.

    http://www.amazon.com/Beatles-Mono-Complete-Recordings/dp/B002BSHXJA/ref=sr_1_1?s=music&ie=UTF8&qid=1390530412&sr=1-1&keywords=beatles+mono

    dougmon

    Posts : 65
    Join date : 2013-11-04
    Age : 60

    Re: VTA-70 and SP-10 impressions

    Post by dougmon on Thu Jan 23, 2014 10:45 pm

    Laminarman wrote:dougmon, you mentioned the Beatles.  By chance you listen to the highly touted mono recordings?  I haven't but I've heard they're spectacular on valve amplifiers.  I'm tempted to buy the collection because I can lose myself in them. If you read the Amazon reviews they're across the board pretty satisfying to most folks.

    http://www.amazon.com/Beatles-Mono-Complete-Recordings/dp/B002BSHXJA/ref=sr_1_1?s=music&ie=UTF8&qid=1390530412&sr=1-1&keywords=beatles+mono

    I have that box, yes. I got it pretty much the day it came out, because I am huge music nerd. The first time I heard the Beatles, it was in mono; and I find that, except for the White Album, I prefer the mono recordings. I think this is one time when "most folks" are right; these recordings are fantastic.

    And now I have this urge to hear "Rubber Soul".

    I have one further impression to share: tonight was the first time I've been able to really sit and listen to vinyl since I got the SP10. What audiophile wonder am I listening to? A ~40-year-old copy of "Home" by Procol Harum. I loved this album as a teenager (I had just turned 13 when it came out), and still like it a great deal. I do have a pretty good phono amp, so that might be part of it, but boy, it's just so great. I wish I had some mono Beatles on vinyl; I only have "Abbey Road", but I'm sure I'll get to that too. My digital setup is pretty decent, but vinyl just gives you a living, breathing performance through this system.

    Laminarman

    Posts : 110
    Join date : 2009-12-30

    Re: VTA-70 and SP-10 impressions

    Post by Laminarman on Thu Jan 23, 2014 11:50 pm

    What speakers are you using? I have vinyl on my radar. I'm now working on and successfully getting my music to stream via an Airport Express with FLAC recordings that I rip from my CD's. So I'll get the SP14, then a DAC, then speakers, and finally a turntable. I gave myself a year to assemble this system but if I sell one of my kids I can do it a bit quicker.

    dougmon

    Posts : 65
    Join date : 2013-11-04
    Age : 60

    Re: VTA-70 and SP-10 impressions

    Post by dougmon on Thu Jan 23, 2014 11:57 pm

    Laminarman wrote:What speakers are you using?  I have vinyl on my radar.  I'm now working on and successfully getting my music to stream via an Airport Express with FLAC recordings that I rip from my CD's.  So I'll get the SP14, then a DAC, then speakers, and finally a turntable.  I gave myself a year to assemble this system but if I sell one of my kids I can do it a bit quicker.  

    I will send you a PM, in which I'll talk about my system in boring detail. Smile

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