Promitheus TVC passive preamp anyone?

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StereoJoe

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Re: Promitheus TVC passive preamp anyone?
« Reply #1180 on: 10 Mar 2007, 05:30 pm »
Sterojoe,
             Yes Joe the source and speakers are key to a fine system. however the addition of a tubed buffer stage[active pre] will enhance the TVCs performance. The active will add additional bloom, air and that organic touch that solid state just cannot offer. If you have not experienced a state of the art preamp in your system you will never know what is truly possible. If distorsion was the only parameter then just buy a SS receiver from Japan say Sony, Marantz or Denon. They all have record low distortion levels but sound OK. The distortion of tubed equip is second order harmonic and actually with SETs sounds quite good.
             The addition of the tubed buffer, when all else is good will bring the sound to a more natural venue. Until you have tried it don't knock it. The addition of the buffer, gain stage will allow for use of a phono stage without the need of a step up transformer for some users as well.
             The main feature of the TVC is the transformer based volume control in lieu of resistor based volume control. So combining both gives best of both worlds IMO. I think that Nicholas is spot on with the active stage and TVC combo.
             Try one for 30 days and if not convinced send it back, but I think you won't.
rollo
Hi Rollo,

I have never had a state of the art preamp in my system - state of the art meaning CJ ART/ACT or even better - the ARC Ref 3. Wouldn't mind spending some time with these, though.
My philosophy when it comes to music reproduction, is to add as little coloration as possible. This is important for every component, specially speakers. What you call bloom, air and organic touch is very nice to have - but it should be present in the recording, not added by the setup itself. Earlyer, I used components witch added such characteristics to the input signal. It killed variation and excitement in the music, and to a large degree made all recordings/music sound the same. Not good!
I can live with the fact that a good deal of my beloved music is not recorded very well. At the same time, I can really appreciate combinations of outstanding performers and excellent recordings.

I don't doubt that Nicolas' tube buffer sounds very good, and can probably make bad recordings more enjoyable. But for me, it is not an option to add another component to the sound chain. If the TVC did sound thin and bright in my system, I would replace it with something else or take a closer look at the sources.

Randy

Re: Promitheus TVC passive preamp anyone?
« Reply #1181 on: 10 Mar 2007, 05:55 pm »
Randy
  Thanks for the info. Do you think it's really worth it to get the balanced version? In price I think it's $20 more, which is minimal, but in functionality I wonder if I'll ever get a balanced input power amp?
Do you know if the internal wiring is the same as the unbalanced version. From the website, I doesn't sound like it is. The unbalanced version seems to have silver wiring while the balanced version doesn't?? Not sure, are you?
tyee

tyee - When Nick came out with the balanced verson he had to redesign the trannies in some way, and then adopted the new trannies for the unbalanced versions as well.  You can read more about this in the early pages of this thread.  For me the balanced version is far superior because of my CDP and amps, which are all balanced.  Though they have unbalanced outs as well, I was used to the balanced usage which is far superior, imo, in all three units. Not sure about the wiring, though, but as I said, this was discussed in those early pages from last fall.  Perhaps the answer to your question is there.
« Last Edit: 11 Mar 2007, 04:20 pm by Randy »

gooberdude

Re: Promitheus TVC passive preamp anyone?
« Reply #1182 on: 11 Mar 2007, 02:30 am »
hey guys,

tweak of the week:  remove all the screws from the TVC.   

If your transformers have the black gunk under them, they are secure (i think!). 

I re-addressed the Source selctor knob issue by adding a piece of sticky 3M double sided foam tape under the mount in lieu of damping & the screws  - works incredibly well.  adhesive damping if you will.

There are no screws on the underside of my TVC now.  of course if I were to transport i'd put the tranny screws back in. 

The selector knob mount no longer flexes when going through the clicks..with the screws in it would.

i've been listening with the lid on/ off and on w/o screws.   In my room, to my ears, lid off is the best sound...so smooooth.   try listening with lid on but no screws.

also, i removed one of tiny allen screws on the collar that attaches the knob rod to the switch.  only 1 is needed on the side of the collar that attaches to the switch itself...its more secure this way on mine.   this go around i tightened down all the other allen screws on the new wood dowel rod...the selector knob action feels more solid now.

overall, this tweak releases the sound...the soundstage gets larger and images sharper.  makes it easiesr to place footers too, no more mine field.

I just started listening to my Ipod with the TVC, quite a thrill.  it drives the sub better than the cable tv box and xbox too.     Imod coming soon...  there's something to a battery powered source with the TVC.

matt



guest1632

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Re: Promitheus TVC passive preamp anyone?
« Reply #1183 on: 11 Mar 2007, 03:59 am »
hey guys,

tweak of the week:  remove all the screws from the TVC.   

If your transformers have the black gunk under them, they are secure (i think!). 

I re-addressed the Source selctor knob issue by adding a piece of sticky 3M double sided foam tape under the mount in lieu of damping & the screws  - works incredibly well.  adhesive damping if you will.

There are no screws on the underside of my TVC now.  of course if I were to transport i'd put the tranny screws back in. 

The selector knob mount no longer flexes when going through the clicks..with the screws in it would.

i've been listening with the lid on/ off and on w/o screws.   In my room, to my ears, lid off is the best sound...so smooooth.   try listening with lid on but no screws.

also, i removed one of tiny allen screws on the collar that attaches the knob rod to the switch.  only 1 is needed on the side of the collar that attaches to the switch itself...its more secure this way on mine.   this go around i tightened down all the other allen screws on the new wood dowel rod...the selector knob action feels more solid now.

overall, this tweak releases the sound...the soundstage gets larger and images sharper.  makes it easiesr to place footers too, no more mine field.

I just started listening to my Ipod with the TVC, quite a thrill.  it drives the sub better than the cable tv box and xbox too.     Imod coming soon...  there's something to a battery powered source with the TVC.

matt

Hi Matt,

hmmm, You just might have something there. Mine has this sticky stuff like tape under each transfoemer. Now, what you've just done is to acoustically  isolate the transformers from the base. Actually, with a rubber groumet, and a couple of washers, one flat washer above and just under the locknut, and one under the base as a finishing washer. So what do you think about that?

Ray

gooberdude

Re: Promitheus TVC passive preamp anyone?
« Reply #1184 on: 11 Mar 2007, 04:10 am »
remove the screws and see if your trannies stay secure.  If so, remove more screws and listen.  the trannies in mine seem to be glued down.

the double sided tape under the switch mount tweak got me thinking.  typically, good things happen when i think.   this is simple isolation.

the plastic baggie holding all the removed screws, nuts and collars rings like a bunch of tiny bells.

just hold some of this hardware and shake your hand...jingle, jingle, jingle. 






F-100

Re: Promitheus TVC passive preamp anyone?
« Reply #1185 on: 11 Mar 2007, 04:14 am »
No offense but you guys must be smoking some good wacky tobacky or have the golden ears in order to detect sonic difference with a few screws removed from the chassis. :)

gooberdude

Re: Promitheus TVC passive preamp anyone?
« Reply #1186 on: 11 Mar 2007, 04:28 am »
Its actually 13 screws and 'The Trainreck' has been flowing through Chi-town lately, thanks for asking.  so green it glows in the dark.   hard to get good local stuff that's not loaded with fertilizer.      aa


these little trannies vibe & a few choice tweaks lessen the damage. 

i'm not advocating removing screws in other gear though, except my TT.  that's a whole 'nother story but with the same outcome.

or maybe i like typing the word screws a whole lot?


screw the screws.


Russell Dawkins

Re: Promitheus TVC passive preamp anyone?
« Reply #1187 on: 11 Mar 2007, 06:40 am »
I would imagine that if removing the screws and then the top improves the sound, then the ultimate tweek in this direction would leave you with something looking like the Altman Attraction DAC:

http://www.mother-of-tone.com/attraction.htm

.. and for good reason, according to Yves Bernard Andre of YBA fame, and Charles Altman.

Either Charles can't make boxes or he's doing it that way because it sounds better. It wouldn't be too hard to find out!

Just take it all apart and mount all the stuff on a slab of pine, cover the pine with some violin lacquer and sell it for a couple of thousand, based on the sound and the time it took to find the right lacquer.  :)

GHM

Re: Promitheus TVC passive preamp anyone?
« Reply #1188 on: 11 Mar 2007, 02:02 pm »
I would imagine that if removing the screws and then the top improves the sound, then the ultimate tweek in this direction would leave you with something looking like the Altman Attraction DAC:

http://www.mother-of-tone.com/attraction.htm

.. and for good reason, according to Yves Bernard Andre of YBA fame, and Charles Altman.

Either Charles can't make boxes or he's doing it that way because it sounds better. It wouldn't be too hard to find out!

Just take it all apart and mount all the stuff on a slab of pine, cover the pine with some violin lacquer and sell it for a couple of thousand, based on the sound and the time it took to find the right lacquer.  :)


Funny you mentioned this Russell. I've started to type in a suggestion, but always stopped. I figured it would drive the tweakers of the group over the edge. I've been told..though I've only experienced this varnish in one of my CD players that it makes a sonic difference.Since the player came with it installed I really don't know. It is called C37 Lacquer and sold here in the states. This stuff is expensive. It can be bought at Reference audio mods. I'm sure there could be other places to buy from,though I haven't seen it any where else.

gooberdude

Re: Promitheus TVC passive preamp anyone?
« Reply #1189 on: 11 Mar 2007, 04:50 pm »
C37 might be straw that breaks the camel's back here!   mounting our gear to proper tonewood boards is no joke, and useful in a host of applications.     spend $ like that on footers &/or a suspended plinth for the this tvc 1st though.

someone with a line into mapleshade (rollo) should find out what lacquer their woodworker uses.  just messin' with you rollo!     

i'd bet dr. sprey found a generic version of c37 to use with his boards, they sound insane.   been listening to 4 difft 4" thick air dried MS boards lately.   they are a wild ride compared to the other tonewood boards i own.   

for the tvc chassis tweaks, does it make sense that the trannies and switch - which is all there is  - are more isolated from one another with all the screws out?    they can do what they do w/o as much intereference from the physical vibrations of the other parts.   

playing with difft mountings of the steel lid resulted in much smaller gains/losses than removing all the screws.  the lid is non-magnetic.

Gymane, are you saying to apply C37 to the inside of the TVC chassis?   all over or just certain chassis panels??   C37 is crazy, stupid expensive.    the finish on my tvc looks to be a lacquer.  since this stuff soaks into the wood and chemically bonds, i wonder if C37 would be as effective (if at all) on an existing tvc versus applying it to a new unfinished case.     its interesting that people shellac expensive single driver set-ups with the stuff.

about a week ago i was posting about the possibility of making a single vol ctrl tvc into a double.  that tweak is many moons away now - the soundstage is more than wide enough after all the recent tweaks.   not only are there no holes in the soundstage, but all the holes are filled in with fleshed out musicians.   quite a trip really.   i've been rockin my ipod and cdp lately & every so often install the Ult Triplepoint footers from my TT under the TVC, in lieu of the cheaper versions of the same model.  if i spend any more $ to make this TVC better, other than the freebie tweaks you all come up with, it'll be on a set of them.  the sound is more than adequate with the smooth top'd 2" footers though.

the added zing, bass imaging and size of the sound the pointed footers add is cool though.



what about damping the underside of the wood bottom'd tvc's?  that wood plate is pretty thin. 

Nick, is anyone in Malaysia doing case mods??


GHM

Re: Promitheus TVC passive preamp anyone?
« Reply #1190 on: 11 Mar 2007, 05:03 pm »
C37 might be straw that breaks the camel's back here!   mounting our gear to proper tonewood boards is no joke, and useful in a host of applications.     spend $ like that on footers &/or a suspended plinth for the this tvc 1st though.

someone with a line into mapleshade (rollo) should find out what lacquer their woodworker uses.  just messin' with you rollo!     

i'd bet dr. sprey found a generic version of c37 to use with his boards, they sound insane.   been listening to 4 difft 4" thick air dried MS boards lately.   they are a wild ride compared to the other tonewood boards i own.   

for the tvc chassis tweaks, does it make sense that the trannies and switch - which is all there is  - are more isolated from one another with all the screws out?    they can do what they do w/o as much intereference from the physical vibrations of the other parts.   

playing with difft mountings of the steel lid resulted in much smaller gains/losses than removing all the screws.  the lid is non-magnetic.

Gymane, are you saying to apply C37 to the inside of the TVC chassis?   all over or just certain chassis panels??   C37 is crazy, stupid expensive.    the finish on my tvc looks to be a lacquer.  since this stuff soaks into the wood and chemically bonds, i wonder if C37 would be as effective (if at all) on an existing tvc versus applying it to a new unfinished case.     its interesting that people shellac expensive single driver set-ups with the stuff.

about a week ago i was posting about the possibility of making a single vol ctrl tvc into a double.  that tweak is many moons away now - the soundstage is more than wide enough after all the recent tweaks.   not only are there no holes in the soundstage, but all the holes are filled in with fleshed out musicians.   quite a trip really.   i've been rockin my ipod and cdp lately & every so often install the Ult Triplepoint footers from my TT under the TVC, in lieu of the cheaper versions of the same model.  if i spend any more $ to make this TVC better, other than the freebie tweaks you all come up with, it'll be on a set of them.  the sound is more than adequate with the smooth top'd 2" footers though.

the added zing, bass imaging and size of the sound the pointed footers add is cool though.



what about damping the underside of the wood bottom'd tvc's?  that wood plate is pretty thin. 

Nick, is anyone in Malaysia doing case mods??




Yes Matt..basically spray the trannies down with the C37 and the inner lining of the chassis. Hell if you can afford it maybe just cover the entire inside with the stuff. I'm pretty open minded,but can't afford to spend money like that. Rollo needs to try it and report back. He is the Promi guinea pig after all. :wink:

gooberdude

Re: Promitheus TVC passive preamp anyone?
« Reply #1191 on: 11 Mar 2007, 05:08 pm »
would it be a good idea to put the stuff on the bare tranny output wires?  i was thinking about
applying the lacquer to the wood, silly me.    :o

are the tranny wires bare?   look to me like they are.   

would covering the innards with lacquer help to stave off oxidation??


Paul_Bui

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Re: Promitheus TVC passive preamp anyone?
« Reply #1192 on: 11 Mar 2007, 05:38 pm »

I don't doubt that Nicolas' tube buffer sounds very good, and can probably make bad recordings more enjoyable. But for me, it is not an option to add another component to the sound chain. If the TVC did sound thin and bright in my system, I would replace it with something else or take a closer look at the sources.

I wholeheartedly agree, and hope that the TVC will sound glorious in your system as it does in mine.  For the very first time I could feel the music simply flowing out of my speakers, with much less forced sound.  IMHO, the Promitheus TVC is a precision sonic microscope that I can use to judge my other components, upstream or downstream.

Dave G

Re: Promitheus TVC passive preamp anyone?
« Reply #1193 on: 11 Mar 2007, 05:41 pm »
Paul,

What's the rest of your system when you're using the Promitheus TVC?  Thanks.

Dave

Paul_Bui

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Re: Promitheus TVC passive preamp anyone?
« Reply #1194 on: 11 Mar 2007, 07:20 pm »
Hi Dave,

The rest are:  RWA SB2 (transport), Altmann DAC, AudioSector Patek, and BB FTA-2000s.  I also have a pair of Clari-T monoblocks, no volume pots, fully upgraded with Black Gates and Audri caps, and they will be next to try with the TVC.

By the way Dave, I like and concur with what you said ealier about your experience with the TVC because it's so true.

"I liked what I heard (the purity of the sound; the clarity; the feeling that a veil had been removed from the music) and the volume was much louder than I'm used to. So, I made the switch, and I'm glad I did. I have no basis for  comparison to other passives, TVCs or active pre-amps, but I do know this: I have experienced absolutely no loss of bass (and possibly some gain). My volume settings are fine (I usually play music at 10-12 o'clock, first time around on the clicks). The clarity is wonderful, and the TVC is especially good at operatic voices. It always seems as if the voicer is in front of the orchestra, rather than the other way around. Most importantly, that electric sound--that's the only way I can describe it--is gone. Now, I only play classical and opera (with a little bit of rock mixed in), and I don't like flavored music at all. Well, the TVC doesn't flavor the music.  And there are times when I'm startled by the clarity (as in, it actually makes me sit up and notice). By the way, when I put my ear to my speakers at minimum volume, I hear nothing. No buzz. Just black."

I may repeat myself if I said it somewhere earlier, but the TVC just lets music flow through, with glorious midrange, highly detailed trebles, deep bass [if exists in the recording] intact.  I am now a TVC convert, although it has only been here for less than a week (4 days to be exact).
« Last Edit: 11 Mar 2007, 07:36 pm by Paul_Bui »

GHM

Re: Promitheus TVC passive preamp anyone?
« Reply #1195 on: 11 Mar 2007, 07:38 pm »
Hi Dave,

The rest are:  RWA SB2 (transport), Altmann DAC, AudioSector Patek, and BB FTA-2000s.  I also have a pair of Clari-T monoblocks, no volume pots, fully upgraded with Black Gates and Audri caps, and they will be next to try with the TVC.

By the way Dave, I like and concur with what you said ealier about your experience with the TVC because it's so true.

"I liked what I heard (the purity of the sound; the clarity; the feeling that a veil had been removed from the music) and the volume was much louder than I'm used to. So, I made the switch, and I'm glad I did. I have no basis for  comparison to other passives, TVCs or active pre-amps, but I do know this: I have experienced absolutely no loss of bass (and possibly some gain). My volume settings are fine (I usually play music at 10-12 o'clock, first time around on the clicks). The clarity is wonderful, and the TVC is especially good at operatic voices. It always seems as if the voicer is in front of the orchestra, rather than the other way around. Most importantly, that electric sound--that's the only way I can describe it--is gone. Now, I only play classical and opera (with a little bit of rock mixed in), and I don't like flavored music at all. Well, the TVC doesn't flavor the music.  And there are times when I'm startled by the clarity (as in, it actually makes me sit up and notice). By the way, when I put my ear to my speakers at minimum volume, I hear nothing. No buzz. Just black."

I may repeat myself if I said it somewhere earlier, but the TVC just lets music flow through, with glorious midrange, highly detailed trebles, deep bass [if exists in the recording] intact.  I am now a TVC convert, although it has only been here for less than a week (4 days to be exact).

Hey Paul I think you have the two Daves mixed up. Those are Davetroy's comments. :lol:

Matt,
Not sure the C37 would stave off oxidation... It probably will. The wires cross and touch one another. So I doubt the lacquer would harm anything .

Paul_Bui

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Re: Promitheus TVC passive preamp anyone?
« Reply #1196 on: 11 Mar 2007, 08:13 pm »
Thanks Gymane for correcting me.  Davetroy and Dave G, sorry for mixing up you two, but I hope you both will forgive me, knowing that the Promitheus has been lifting me up from ground for the last few days.

rollo

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Re: Promitheus TVC passive preamp anyone?
« Reply #1197 on: 11 Mar 2007, 08:35 pm »
GHM, Gooberdude,
       
         Yes C-37 is very expensive. I use artists varnish with great affect. The key is the type of wood. Spruce appears to be the best choice to date. Remove the bottom plate and replace it with a 3/4" th. board to fit into the recess from the SS plate. The wood will extend past the bottom acting as a base as well. Then take the ebony cones and walaski your in.
        Now remove top plate and place a smaller piece of treated spruce across both trannies[say 6"x 8"] and some weight[ brass, lead sinker weights, etc.] on top.
        Applying the lacquer to the finished enclosure will not do much as the lacquer needs to be absorbed in the wood somewhat to be effective.
The wires from the trannies are coated, so additional coating is redundant with no affect.
        The ultimate enclosure would be ebony. Unfortunately that would be cost prohibitive. If you want to try ebony under the trannies, buy pen blanks and install them under the tranny like railroad tracks. Screw tranny into ebony and glue ebony to surface below.
        Speaking of the transformers, I would like to see a copper shield and hemp paper surround the wires wrapped around the core. I would also like to see a completely shielded enclosure with drain [ground] with the transformers mounted on ebony.
        I have mentioned to Nicholas that a statement edition with the above and Neotech 7N copper wire for the trannies and internal wiring would be very interesting.
         The active preamp or buffer adds the best of both worlds and can be ordered to match your systems requirement for gain. The pre comes with a 6N1p tube. Nicholas is making one which is 2A3 based for a friend of mine. I will have the pre in approx a week and let you all know of the results. Besides adding balls to the presentation the added gain will eliminate any need for a step up transformer for low output moving coils for our vinyl.
    No I did not say the TVC has no balls, the active just gives you more. For $450 for the pre you are under $1000 for it all. Remember the Promitheus pre is designed to be used WITH the TVC. Your active pre is not. Although it works IMO the Promitheus will sound better in this application.
   For your information Ron Bauman of Mapleshade has been selling a passive pre based on a custom resistor based attenuator. They make their own resistors with a microscope[ really small] from NASA sourced materials. It ain't cheap. I brought the Promitheus over to a friends home who has the Mapleshade unit and he was so impressed that Ron is seriously considering making one for himself. Enough said.
   I am in the process of co- designing a transformer output based CDP. The trannie will replace the analog section and simply add gain to the signal. This design will allow the user to use the analog section of an active and TVC combo or just the TVC which is much better than the analog section of the CDP or many actives for that matter.
   IT is Sunday and pasta time at the moment so see ya all later. Guinea no pig maybe, I'm having 2 plates of pasta.
  Almost forgot the Altman DAC. May sound real good but $1350 for a circuit board and connectors on a piece of lacquered spruce is a little too much to bear. If it was priced like the TVC, it would have 120 pages of threads. Fahn fahn fahn down the autobahn.

rollo

rollo

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Re: Promitheus TVC passive preamp anyone?
« Reply #1198 on: 11 Mar 2007, 08:43 pm »
Dave and Paul,

   Welcome to the good ship promitheus. You are going to like the tripath and TVC combo. It worked real well in my system [stock] the modified unit should be killer.

 rollo

jonners

Re: Promitheus TVC passive preamp anyone?
« Reply #1199 on: 11 Mar 2007, 08:44 pm »
would it be a good idea to put the stuff on the bare tranny output wires?  i was thinking about
applying the lacquer to the wood, silly me.    :o

are the tranny wires bare?   look to me like they are.   

would covering the innards with lacquer help to stave off oxidation??



The tranny wires are insulated (and protected from oxidation) by a thin coating of something like polyester.

Since having my TVC I've become very aware of how small changes in L-R balance can affect the soundstage in my system. I found that a small reduction of volume in one channel (0.5dB to be exact) led to instruments becoming more focused and the soundstage more stable and 3-D. I would really like to be able to make smaller changes to see if I can fine-tune it further, but 0.5dB is my lower limit at present. I wonder if anyone else has noticed anything similar?