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    My New VTA pre-amp

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    Tube Nube

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    My New VTA pre-amp

    Post by Tube Nube on Thu Feb 24, 2011 9:23 pm

    Greetings forum friends,

    I'm writing to you today to report my first impressions upon taking delivery of my new VTA pre-amp.

    As building the amp proved beyond my capability, I had our friend Roy Mottram build it for me. Maybe I should take some pictures of the insides -- it is a clean and tidy, professional job, to be sure.

    Was it the design, or was it the care he took to twist all possible internal wiring that makes this pre amp so quiet, compared with my Transcendent GG pre amp? Maybe Roy will see my post and take my invitation to set modesty aside in offering his thoughts.

    The amp is quiet. I can hear the GG hiss from my listening position, when no music is playing. Not the VTA.

    Solid build, no hiss! We're off to a great start.

    But enough of what's good about what I don't hear, what is it I DO hear?

    As I mentioned to Roy, in an earlier email, one of my favorite comparison pieces is Ricky Lee Jones' Easy Money. Ultra High Fidelity magazine recommends this piece for just this comparison. There's great vocals, prominent upright acoustic bass, guitar, tinkly precussive things like tambourines or whatever -- lots' of complex stuff for you to judge what sounds more or less realistic.

    Right off the bat the sound with the VTA is just "fuller" compared against the Transcendent. (played at the same volume).

    There's more detail in the sound -- a sense that there's more to it, more there than what I was hearing before. You know the cliche..."I was hearing things I didn't hear before..." Well, I'm not sure if that's exactly right. But more to what I was hearing.

    More dynamic variation, too. So, all together, along with other attributes I haven't even noticed yet I'm sure, I found the sound more engaging.

    My son, himself a musician, chimed in with noting there was more separation between the instruments playing.

    So, fuller, more natural, more detailed sound, a better sense of soundstage, or perhaps "image" contributing to more engaging, more enjoyable musical performance.

    I haven't actually added up the total costs of each for a comparison, but I think the cost was pretty comparable. Especially if excluding the cost of the phono board option which I got --the Transcendent doesn't have an on-board phono stage.

    I'll probably continue to do some more A/B comparisons, just for the fun of trying to make careful note of how they differ. But in terms of value for money, I'd say it's not even a close call. This will surely prove self defeating to say this, should I seek to sell my Transcendent here on the forum's For Sale section, but I would really be surprised if anyone hearing these two pre amps would opt for the Transcendent.

    I've really enjoyed my TS pre amp, and have no complaint against it at all, but side by side with the VTA, I would opt for the VTA, even if double the cost. Even triple the cost.

    So, those are my initial impressions.

    Hopefully I'll have more to follow.

    Brenton


    tubes4hifi
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    Re: My New VTA pre-amp

    Post by tubes4hifi on Thu Feb 24, 2011 10:28 pm

    This must be from Brenton, thanks!
    very nice review and always happy when the customer is not only satisfied but surprised at the sound quality and value. I started Vacuum Tube Audio (www.tubes4hifi.com) 25 years ago as a hobbiest looking for the best tube audio products for the best price, and felt most of the DIY products on the market were only fair quality and only fair to overpriced, so I started designing and selling products to maxify quality and value for the price.
    Tube preamps are an especially difficult product, and today's customers have changed alot from customers even 5 years ago. My aim is for the DIY person (do-it-yourself) and yet this past year almost half of my preamp sales are from people who don't DIY - they just want good value. They can afford to buy new Audio Research or Conrad-Johnson products, but they seem to be realizing that why buy a $6000+ preamp when you can buy one just as good for around $1000 (or less as a kit!!).
    I used to sell maybe one preamp a month, now it's 2 or 3 a week, so just to let any potential customers know, the waiting period is about 3 weeks on kits, and 4-5 weeks on finished preamps.
    Also please note, as Brenton found, unless you have alot of tube electronics experience, preamps are not a simple project like building an ST70 amplifier. I do NOT provide detailed instruction, I DO provide a schematic, parts list, PCB layout diagram, and a general wiring diagram as a drawing. That's it. I can't answer 3 dozen emails if you don't get it.
    So I get some customers that buy kits, and a week later they are sending me great news that it works incredible.
    But most customers are asking dozens of questions, and if they can't figure it out in a week or so, I recommend that they let me build the preamp for them, I can build it alot faster than I can answer questions and try to teach you 40 years of electronics in 4 days. I'm sure Brenton can respond and let you know that the money spent to have it built right was well worth it, even if maybe he didn't learn as much about how it all works as he might have liked, but his reward is in the daily listening of the music, and THAT is what it is REALLY all about!!
    Thanks for your support, your comments (good and bad), your patience with the wait, and most of all . . .
    ENJOY the music and the magic of tube audio !!
    Roy www.tubes4hifi.com

    tubes4hifi
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    Re: My New VTA pre-amp

    Post by tubes4hifi on Thu Feb 24, 2011 11:03 pm

    another note on the sonics - I can't resist, as I have had a Transcendence GGP also in the past (I often buy medium and hi-end preamps to compare), and I know Bob Latino (our forum moderator) had a Transcendence at one time also.
    In my mind, Transcendence has some very good products and designs, but the end result isn't as satisfying.
    ONE of the reasons I strongly believe is because they (and others, take note Bottlehead friends) is they use solid-state power supplies trying to save $10 (on a $500 kit). Believe me, in my experience, a tube rectifier is most definitely what you want in a tube preamp. It has SO MANY advantages, and zero disadvantages other than the fact it needs power itself (tube filaments) and you might lose 10-20 volts of B+ power (so what?!).
    A tube preamp without a tube rectifier is only HALF as good as a tube preamp WITH a tube rectifier.
    Sorry, my opinion, but one I feel very strongly about, I've heard alot of preamps, including the Transcedence, and dozens of others. You can make the Transcendence (and most of the others) sound twice as good by replacing the power supply. I built the kit both ways. Even with a solid-state REGULATOR after the tube rectifier, I can hear the difference in the sound, the SS regulator has less effect (and mostly good effect) on the sound quality than the tube rectifier does.
    The other thing I'd like to point out is that although the Transcendence is a good design, they cut alot of costs on the packaging, that's an awfully generic aluminum box it's in.
    I must say, the price of my own preamp kits is mostly influenced by whether you just want the circuit and if you want it in a nice box. The box, the packaging, is expensive. You can get that $5000 sound for $500, but if you want it to LOOK nice, it's probably gonna cost you more like $1000.
    Last point to make (my own opinions of course) is I try to pick the best parts for the VALUE.
    Not the cheapest parts, not the best parts. If you are buying a $500 kit, do I think you would like 15 cent resistors instead of 5 cent resistors - YES, it's a $2 total increase in price. Do I think you would like $2 capacitors instead of 25 cent capacitors - YES, it's a $2 total increase in price. Do I think you would rather have a good quality volume control (ALPs blue velvet) rather than a fair quality volume control for an increase of $15 - YES. So hey, my $500 kit went up in price maybe $30 total, but it's got MUCH better parts in it.
    But hey, do I think you want $20 capacitors instead of $2 capacitors? Only if YOU want - I can barely hear the difference. You might want that stepped attenuator with discrete resistors instead of a variable pot made from carbon or conductive film, so yeah, it's worth the extra $20. Do I think you want to pay $100 for a selector switch (those GoldPoints are very popular) actually is it really worth it over the $5 switch ?? that does the same thing, it's still a silver contact to silver contact point.
    So yes, you can customize to your own specs and to your own price, no problem! But even the stock parts are better than what you get elsewhere.

    Tube Nube

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    Re: My New VTA pre-amp

    Post by Tube Nube on Thu Feb 24, 2011 11:14 pm

    Hi Roy,

    Thanks for jumping in!

    I really don't think I could fairly offer any bad comments. While I'd like to have been able to build it myself, I knew it would be a challenge based on your cautionary note on your website, and took a chance. Here was my reasoning: Based on the strength of Bob Latino's review of your SP8, and a favorable comparative comment by him on the SP vs the Transcendent, I decided this was a pre-amp to get.

    Knowing you offered to build them was enough reassurance for me to take the risk, so if I was really over my head, I wouldn't be stuck. I took the chance and I was, indeed, over my head.

    So, added to the cost of the amp, was the extra transit costs of shipping to and fro, but in the value for money equation, I'm still laughing about what a great product I've got, and still a bargain.

    I have to confess that before I got to the quitting point on finishing the build myself, I think I made a bit of a pest of myself. Roy was generous in his responsiveness to me, but after, oh, maybe 10 rounds back and forth, on multiple different issues (over a prolonged period), I decided not only couldn't I do it, but it wasn't fair to Roy to keep asking his help.

    I had this project sitting on my table for months. Once I contacted Roy about finishing it for me, it was literally only 3 weeks door to door to door.

    So again, my thanks to Roy for a good product and for his great service -- especially the rescue build/re-build.

    I'm really glad to hear Roy is besieged with success in witnessing such increasing demand for his products. It's great when you see good work "amply" rewarded.

    Now, off to spin a record...


    Tube Nube

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    Re: My New VTA pre-amp

    Post by Tube Nube on Fri Feb 25, 2011 11:54 am

    I was interested to read Roy's comments in his second post, above, about differences in power supply construction, tube rectification, and component quality as factors contributing to differences between his amp and the competing Grounded Grid preamp.

    It makes a lot of sense to opt for components that are better than cheap, but without going all the way to "exotic", unless specifically requested. This was one of the nice features of the kits offered both by Roy and by Bob--they lay out some options for the customer to choose better resistors and capacitors and tubes, etc, with the associated costs.

    I wish I knew a bit more about how these circuits worked so I could have a more informed opinion about things like tube rectification -- I think I'll set my self a project of doing some reading. But it's something I'd read on another forum, the Crossover Network, I think it was, that was along the lines of what Roy was saying. Basically that the view was it was ashame not to have tube rectification in a tube amplifier, as it somehow held back the sonic advantages of tube design.

    Tube Nube

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    Re: My New VTA pre-amp

    Post by Tube Nube on Fri Feb 25, 2011 12:08 pm

    Another observation about the sound of my new pre amp.

    I notice I'm listening with greater satisfaction at lower volume levels. Partly, I believe, it's the greater dynamics, making the stereo play louder on the crescendos than with the TS pre amp.

    Another point here, I recall reading in UHF that there is a tendency to turn up the volume in order to hear more in the music, but when the equipment does a better job of bringing out the detail, there is less need to crank it. I only remembered this after observing that I was turning the music down.

    Tube Nube

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    Re: My New VTA pre-amp

    Post by Tube Nube on Fri Feb 25, 2011 1:38 pm

    I believe my amp is designated as the PAS-3 ZMod, or something like that. It came after the SP8 circuit board was broken into 2 or 3 separate boards to allow for more options. I ordered mine with upgraded bits and pieces. Step attenuators (volume, and separate right and left gain controls), upgraded capacitors and resistors. Maybe the power supply as well. Don't recall. : / Sorry.


    polarflu
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    Re: My New VTA pre-amp

    Post by polarflu on Fri Feb 25, 2011 2:51 pm

    I know this a little off topic, but what does a preamp add if you are only using one source. This is in reference to adding Bob's attenuator kit to my ST70. I run everything through my DAC so I am strongly considering the attenuator for my amp. Comments?

    Tube Nube

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    Re: My New VTA pre-amp

    Post by Tube Nube on Fri Feb 25, 2011 3:05 pm

    That's a great question to which I don't know an answer.

    I am aware, however, of such a thing as a "passive pre amp", which, iirc, amounts to the same thing as the attenuator like Bob offers to place between the power amp and the line-level source like a CD player.

    My main source is vinyl, so I need lots of amplification -- not only the pre amp, but a phono amp ahead of it, and a step-up transformer for the low output moving coil cartridge ahead of that.


    tubes4hifi
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    Re: My New VTA pre-amp

    Post by tubes4hifi on Fri Feb 25, 2011 4:21 pm

    nice responses,
    Hi there PolarFlu, yes, if you only have one source and you have a volume control, you're probably not going to need a preamp, which acts as a control station to select various sources, control volume and balance, and add some gain where needed.
    As for alternatives, I'm always trying to keep track of what is out there.
    The AudioNote stuff is very good, premium parts, and premium prices. Plus you get a GREAT instruction manual that anyone could understand, it's about 80 pages. For that, a preamp kit runs $1500, compared to around $610 for my SP8 kit. The Bottlehead stuff I'm sure some may disagree, but I don't consider it as good quality or sonically equivilent, the standard Foreplay 3 line amp only is $489 and the Seduction phono amp kit is $369 so you've got a total of $858 there. It would compare more to my basic Zmod upgrade for the PAS3 which would total $249 with tubes but without a chassis. The Transcedence Grounded Grid line amp kit is $499, and their Phono pre is $699, for a total of $1198, both good quality and good sonics, easy to upgrade (not that they offer upgrades.)
    If anyone else knows of some good quality tube preamp kits for under $1000 that I haven't mentioned, let me know

    crxman

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    Join date : 2011-01-04

    Re: My New VTA pre-amp

    Post by crxman on Sun Feb 27, 2011 7:07 pm

    Hi All,

    I recently purchased the PAS Z Mod kit from Roy. It has the PC5, PC6, and the Regulated power supply board. It is very similar to the SP8 except on 3 boards... This was my first kit. I had just purchased Bob Latino's ST-120 and was preamping it with a stock PAT5... Roy was really great at giving me all the assistance that I required and I followed his theory of floating the ground and it all looks just great. The preamp is dead quiet, no hum at all. It makes the PAT 5 sound like it was running the speakers with pillows on them. The sound from highs to bass is perfectly clear and the soundstage sounds very much expanded.
    Roy supplied his custom chassis and gave me an input selector with 6 inputs because I wanted the extra input. The front and back plates are beautifully etched and the whole project is indeed one that you can take pride in... It looks as good as it sounds...
    Thanks again to Roy for all his patience and help.

    Arnie from Philly

    Tube Nube

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    Re: My New VTA pre-amp

    Post by Tube Nube on Sun Feb 27, 2011 7:52 pm

    Arnie,

    Sounds like the same set up as me. I think you're having similar auditory experiences as me.

    All of a sudden, it seems to me my speakers have much better bass response. Didn't make sense to me that my speakers should lack bass, as they're massive. Now I know why! The new pre amp is the difference.

    "Floating ground". See, you've obviously got a better grasp of this stuff than me to be able to have built it yourself. Well done!

    Bob Latino
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    Re: My New VTA pre-amp

    Post by Bob Latino on Sun Feb 27, 2011 8:35 pm

    If you only have ONE high level signal source and don't need a tape loop or tone controls, the stepped attenuator is an easy way to get good sound out of your Dynaco tube amp without the use of a powered preamp. There are many audiophiles that use either a passive resistor based volume control or a TVC (transformer volume control) in place of a powered preamp. Many tube or solid state preamps add a "sonic signature" to the overall sound of your music system - some preamps do it more than others. Crxman's Dynaco PAT-5 as mentioned above is a good example. A STOCK Dynaco PAS-2 or PAS-3 sounds a little flat and "lifeless" in it's stock form. The sound from a stock PAS is not annoying in any way, the music just lacks a little clarity and "jump". When you compare a stock PAS to a modern tube preamp like one of Roy's tube preamps you will notice that your amp now sounds cleaner. Acoustic instruments now sound more like "the real thing". The soundstage is wider and deeper. Crxman's statemet above of "The sound from highs to bass is perfectly clear and the soundstage sounds very much expanded." is quite true.

    Bob

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