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    Preamp, or not to preamp...That is the question.

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    polarflux

    Posts : 49
    Join date : 2010-02-12
    Location : Alaska

    Preamp, or not to preamp...That is the question.

    Post by polarflux on Tue Jan 24, 2017 12:13 am

    Really, I'm just itching to build something and naturally, already being an owner of the superlative Tubes 4 Hifi ST70, building one of the preamp kits would fit the task nicely. The question is, would there be any sonic advantage to throwing in a line stage? I am already feeding my DAC directly into the ST70 via the attenuator mod. The DAC has plenty of buzz to drive the ST70. But, really, would something like the SP14 drive a better signal or would I just be wasting my money? The only known justification I can think of is a preamp would give me a bit more control over the volume compared with the passive attenuator. I've also been scratching the vinyl itch, so there is that. I used to have a fairly nice non-tube preamp that I sold after installing the attenuator. There was a definite improvement in the sound after chucking said preamp from the chain, but then again the preamp was not amazing so that was not particularly surprising. Thoughts?

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    Kentley

    Posts : 422
    Join date : 2015-03-06
    Age : 64
    Location : Worcester, MA

    Re: Preamp, or not to preamp...That is the question.

    Post by Kentley on Tue Jan 24, 2017 12:56 am

    Our little community is, it seems, fairly evenly split on this question. I took the liberty of going through your posting history to see what other equipment and experience you've had and I would say that, for someone with your refinement, the addition of one of the VTA preamps would be a genuine revelation. Personally, I immediately found my ST-120 sound was enhanced greatly with the addition of the SP-14. Everything I liked about the sound was - well - more better. And here's a real plus for you who have the stepped attenuator installed already -- you can vary the ratio of preamp gain to power amp gain to unleash a whole spectrum of new subtleties. Lately, I've been running the SP-14 at max and using the ST-120 attenuator to control volume. I just like the sound better. Additionally, you can adjust for best S/N ratio with this dual-control setup.
    To me, therefore, the addition of a VTA pre to your system would provide much more benefit than merely a refinement of your control over volume.
    Of course, then you will want a phono pre.....thereby making yourself, Bob, and Roy Happy Campers!!!
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    polarflux

    Posts : 49
    Join date : 2010-02-12
    Location : Alaska

    Re: Preamp, or not to preamp...That is the question.

    Post by polarflux on Tue Jan 24, 2017 3:09 am

    Refined...I'm flattered, but you should ask my wife. jocolor Thanks for the input. I had not thought about the possibility of playing with various gain configurations. The story keeps getting better and better.
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    corndog71

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    Join date : 2013-03-19
    Location : It can get windy here

    Re: Preamp, or not to preamp...That is the question.

    Post by corndog71 on Tue Jan 24, 2017 10:16 am

    Having lived with several tube preamps over the last 14 years or so I can attest to the VTA SP13 as the best I've had in my system. As appealing as the idea and simplicity of a passive control may be, the performance of a good preamp always wins when it comes to dynamic control of the signal.
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    Zimmer64

    Posts : 117
    Join date : 2013-01-29
    Age : 53
    Location : Switzerland

    Re: Preamp, or not to preamp...That is the question.

    Post by Zimmer64 on Tue Jan 24, 2017 3:20 pm

    I run a SP14 in front of the VTA ST70. A great combo, which I would recommend any time.
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    wgallupe

    Posts : 112
    Join date : 2014-05-18
    Age : 63
    Location : Central Mass.

    Re: Preamp, or not to preamp...That is the question.

    Post by wgallupe on Tue Jan 24, 2017 4:50 pm

    I have had many solid state preamps over the years. The two passive preamps I owned were a PS Audio many years ago and more recently a McCormack TLC-1 for a few years. Both were very transparent but ultimately I found them to lack dynamics. I replaced the TLC-1 with a vintage Threshold SL-10 which made me realize just how important a clean, active preamp can improve sound quality. I have since replaced the Threshold with a VTA SP-13. All I can say is that it is outstanding driving a VTA ST-120 (now sold) and my current VTA Mark III mono blocks. I will never go back to a passive preamp...
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    j beede

    Posts : 394
    Join date : 2011-02-07
    Location : California

    Re: Preamp, or not to preamp...That is the question.

    Post by j beede on Tue Jan 24, 2017 11:13 pm

    During a recent listening session I was stunned by the width and depth of a certain choral recording. I paused and removed the PAS2 that was driving my MkIIIs expecting even better results. To my surprise I got dull and lifeless sound. I came away from that experience with renewed interest in preamp output impedance. Having said that, I will add that the PAS output impedance is enigmatic.

    Dogstar

    Posts : 238
    Join date : 2014-06-23

    Re: Preamp, or not to preamp...That is the question.

    Post by Dogstar on Tue Jan 24, 2017 11:28 pm

    Of all the preamps I own or have owned the only tube amp I'm happy with is actually a John Broskie ACF-2 Tube Buffer. The two VTA preamps I owned were an SP10 and an SP12 and they both had hum that no matter what was tried would not make it go away. The ACF-2 was dead quiet from its very first startup. I'm currently using it with a Tubelab SSE amp

    I also own a Cary SL-100 which is what I currently use with my VTA-120. I like that it it has a remote and allows me to have multiple sources....though I do need a phono preamp to listen to vinyl LP records. I also have a McIntosh C36 which is dedicated to my McIntosh system. I also have a Parasound preamp which will one day be used with bi-amped system.

    I've tried all the preamps with my VTA ST-120 and at one time I thought a preamp was needed to enhance the sound. I though the extra gain was needed to give the music more life.

    As it turned out once the tubes have been conditioned the best sound I have found is when the source is connected as directly into the amp as possibly. Any additional component between the source and the amp either adds distortion or colors the sound.

    I remember back in the 70's one audio manufacturer advertised that the best audio system included a sound source and a pair of speakers and in between there is a straight wire with gain. That straight wire being the amplifier.

    To some that ability to color the sound with more tubes is desirable and that's fine. But you are also adding distortion. Of course psychologically people may like hearing that distortion thinking that is the life they think the preamp provides.
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    pedrocols

    Posts : 96
    Join date : 2014-11-24
    Location : Western MA

    Re: Preamp, or not to preamp...That is the question.

    Post by pedrocols on Wed Jan 25, 2017 1:21 am

    I have tried two solid state pramps and two BAT tube preamps. However, I did ultimately settle for a passive preamp. I have literally tried 5 different passive preamps and currently using a passive preamp based on LDR ( Light Dependant Resistor).
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    deepee99

    Posts : 1602
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: Preamp, or not to preamp...That is the question.

    Post by deepee99 on Sat Feb 25, 2017 4:31 pm

    Get an SP-13 or -14 with big-arse coupling caps and all will be well no matter what you strap to it.



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