[Randy]

"On construction. The nobs are not quite centered..."

What do you mean by "not centered"?

[GHM]

What's the input sensitivity of your Nuforce amplifiers?

NuForce doesn' publish the input sensitivty for any of their amps. Nor, do they state the output voltage for their preamps. Can't find that info in any reviews, either.

It would also be helpful to know the output of his Audio Sector Non OS dac.

Thanks DM and Steve..I didn't know Mike used the AS Dac? I talked to Peter about this. As Steve states it is dependent on the resistors used. Peter supplies 2700 ohm resistors. So I take this as the output impedance. AFAIK the output voltage is 2 volts.

"On construction. The nobs are not quite centered..."

What do you mean by "not centered"?

Yup Randy...I've seen one other person post this. Mine seems normal..I don't know. Maybe the wood worker was having a bad day?

Hi all, my apologies but this morn I don't have time to reread the thread.
Has anyone tried the Charlize with the P. TVC ? I have a kit to build this winter, and 3886 and 3875 gc's. Also interested if anyone's tried it with tube amp? I may look for an ebay el34 or el84 .
Thanks, Don

I wish I could help you Don..I have no experience with that unit. Greg uses a modified T amp from bolder cable also with great results. The input should be around 10k ohms..I'm guessing here? The TVC will drive loads easily down to 4k ohms from what I've been told.

[Steve Eddy]

Thanks DM and Steve..I didn't know Mike used the AS Dac?

Me either. I was just assming darkmoebius knew somehow. 

I talked to Peter about this. As Steve states it is dependent on the resistors used. Peter supplies 2700 ohm resistors. So I take this as the output impedance.

Roughly, yes. The current sources driving the DAC's output don't have infinite output impedance so the output impedance of the DAC itself will be somewhat less than the I/V resistors.

AFAIK the output voltage is 2 volts.

Well, the TDA-1543 is rated to have a full scale output current of 2.3mA. Into 2700 ohms, that comes to more like 6 volts. Ideally that is. The current sources aren't ideal so it'll be somewhat less than that.

Anyway, lowering the value of the I/V resistors will be good all around. The DAC is driving a lower load impedance, the TVC is being driven from a lower source impedance, and the system has less excess gain. Win/Win/Win. 

se

[darkmoebius]

You remind me I've had one here for over a year now that I still haven't got 'round to assembling.

Don't feel bad, I've got one of Tubelover's TDA1541A kits that I quickly assembled, really liked, then took it apart for a new chassis and some upgrades yet never touched it again. That was November of 2004.

It just so happened that I picked up a 2005 upgraded Museatex Bitstrea a few months later and never got back around to the kit. I really need to finish that with upgrades.

[Steve Eddy]

Don't feel bad, I've got one of Tubelover's TDA1541A kits that I quickly assembled, really liked, then took it apart for a new chassis and some upgrades yet never touched it again. That was November of 2004.

It just so happened that I picked up a 2005 upgraded Museatex Bitstrea a few months later and never got back around to the kit. I really need to finish that with upgrades.

Hey, how 'bout we each make a little Fall/Winter project out of them?

se

[darkmoebius]

Hey, how 'bout we each make a little Fall/Winter project out of them?

I'm in, my girlfriend has given me a "use it or lose it" ultimatum about my audio projects. I've got so much stuff just sitting around unused or unfinsihed.

[Steve Eddy]

By the way, something that may not have been terribly obvious from the fact that reducing the value of the I/V resistors reduces the output of the DAC is that a variable I/V resistance would allow you to kill two birds with one stone; I/V conversion and volume control. And the interesting aspect of this approach is that output impedance would behave like that of a TVC, i.e. lower and lower as you reduce the volume.

And, if you buy into the argument, also as with the TVC, none of the signal is "wasted as heat."

I'd been thinking about this several years ago and was going to buy one of Scott Nixon's DACs to do some experimenting with it, but dragged my feet for a year until Peter was kind enough to send me one of his DACs, and then dragged my feet some more until here I am still sitting with the thing sitting unassembled in a drawer.

Anyway, something to think about for those who aren't such foot draggers as I am. 

se

[Steve Eddy]

I'm in, my girlfriend has given me a "use it or lose it" ultimatum about my audio projects. I've got so much stuff just sitting around unused or unfinsihed.

Know what you mean. Sad to have nice things sitting around just collecting dust.

By the way, do you have a URL for Tubelover's DAC?

se

[randytsuch]

By the way, something that may not have been terribly obvious from the fact that reducing the value of the I/V resistors reduces the output of the DAC is that a variable I/V resistance would allow you to kill two birds with one stone; I/V conversion and volume control. And the interesting aspect of this approach is that output impedance would behave like that of a TVC, i.e. lower and lower as you reduce the volume.

And, if you buy into the argument, also as with the TVC, none of the signal is "wasted as heat."

I'd been thinking about this several years ago and was going to buy one of Scott Nixon's DACs to do some experimenting with it, but dragged my feet for a year until Peter was kind enough to send me one of his DACs, and then dragged my feet some more until here I am still sitting with the thing sitting unassembled in a drawer.

Anyway, something to think about for those who aren't such foot draggers as I am. 

se

I built Peter's AS dac a while ago, interesting idea to combine the IV resistor and volume functions into one item.  I may try that, but I have a bunch of other projects I am trying to get done.  BTW, Peter's dac is an easy build if you don't care about appearance.  Mine is "open chassis".  I used some screws for legs, otherwise I just built it up with the parts Peter supplied, and it is just sitting there.

Randy

[gooberdude]

this tvc is a peach.    its character has changed a lot these last few days, burn in is a joy so far.


what interconencts are ya'll using with this?  speltz's anti-IC's are a match.

i've experimented with 5 cables: Mapleshade Clearview, Promitheus silver, Heartland cable w/eichmann's & 2 versions of speltz's anti-IC w/eichmann's (new & old).   

the Heartland is a bad match anywhere in the chain, everything gets slower and dark.

Nick's silver IC is settling down nicely too, it was bright but is warming up.  this cable throws a huge soundstage compared to the anti-IC. i'm gonna let it break in for a few weeks before posting my thoughts.   do order a set though if you're going to purchase this TVC.

The CMC rca's are worth every penny.   my TVC is the Reference one pictured on the nick's site and here on p.27. It has a mixture of the stock & silver rca's.   i've been A-B'ing the 2 types, both for input & output.    if i were ordering again i'd get the CMC's all around, but i don't mind being the guinea pig in this case.   aa          the difference between the 2 is not one of tone (silver vs copper)... the CMC's just let more signal through, at least that's i think i'm hearing      the stock rca's have an effect similar - though not NEARLY as severe - to using the heartland cable from a source to the TVC. 

the stock rca's are high quality but the CMC are a better design.   nothing is fully burned in yet though.   

my Muse 100 amp is getting a set next week, along w/new cablepods.    i think the sweet character of the Muse is gonna dig the clarity & smoothness of the silver rca's.   they are really, really heavy. milled from a solid block of silver.

i've had absolutely no issues with hum.  w/any input selected you can crank the volume to 90% (assuming source is on but not playing) and not hear peep out of your speakers.  it is so damn polite.
   
Go Bears!         

GD

[bikes and beats]

On IC's
I'm using Cardas the same Cardas 300B Microtwin IC's I've used for years between the TVC and my Nuforce amps. I highly recommend them. I did try the silver IC's I got with the TVC but they were not to my liking at all. FWIW, I think the Cardas have way better bass and make the listening more mellow and pleasureable. Right now, I've taken the in-line attenuators out and am letting Mark Kopfler run full blast.
On Sub use.
I'm running a second set of cables to my rather basic Parts Express sealed 10" sub. I've NEVER has this kind of bass control and weight before. I really think the TVC is helping. It just gets out of the way of the music so thoroughly. Hard to believe I have no tubes at all in this system!
-AND- in case the discussion above was pertaining to my system, I have no external DAC. Just a Sony 3100es DVD/SACD player running straight to the TVC. Maybe an NOS DAC in the future? We'll see.
-out  aa

[xsb7244]

Nicholas,

inquiring minds want to know about:
1.  hybrid amp. is this one enclosure or two separate enclosure amp to play stereo
2.  CD transport to match your DAC at around 320-350 USD. after 7 years dispose of transport when laser
expires.  if your DAC is as good as your TVC nothing can stop you.
3.  need picture of your power energizer.

[Steve Eddy]

I built Peter's AS dac a while ago, interesting idea to combine the IV resistor and volume functions into one item.  I may try that, but I have a bunch of other projects I am trying to get done.

Don't do it. I did some asking around and came to find that it won't work with that DAC chip.

Ah well. Win some, lose some. 

se

[randytsuch]

I built Peter's AS dac a while ago, interesting idea to combine the IV resistor and volume functions into one item.  I may try that, but I have a bunch of other projects I am trying to get done.

Don't do it. I did some asking around and came to find that it won't work with that DAC chip.

Ah well. Win some, lose some. 

se

Oh well, that's too bad, seemed like a cool idea.  But, I already have too many projects to work on, so it is probably just as well.  I do still plan to try lowing the i/v resistor value, since I have more gain than I need.

Randy

[darkmoebius]

By the way, do you have a URL for Tubelover's DAC?

I forgot to mention that it is a parallel TDA1541A dac with tube output stage that can use  a 6c45 SE, 6DJ8 SRPP or AD844 opamp. The kit came with all parts needed except 18V transformers, chassis, and rca's.

Tubelover's new website is working, but there isn't any info up yet. Here is the original thread(45 pages) with pictures of his version 1 & 2 PCB's plus complete circuit and parts description.

Believe it or not, I spent all of tonight searching for the dac board and cannot find the damn thing anywhere in my hobby room. I can't find the original box, either. Oddly, I keep everything, religiously, but there's nothing here!!! This is driving me crazy! The only thing I can think is that my EE brother was real interested in it last Christmas when he was down here. Maybe I gave it to him because it wasn't getting used.

I threw out a bunch of empty boxes 6 months ago, I hope it wasn't in one of them.

Damned shame because it was the heaviest and best looking pcb board I have ever laid hands on. The dac allowed for all kinds of experimentation.

Now I'm wondering what else I've lost.

[anubisgrau]

on the nick's page with reference TVC there is announcement for a new alps pot - could it be that there will be a motorized option.

also - sorry about asking this - but could be that despite a rather nice wooden finish, the TVC's look won't fit into my room which is completely white. i am wondering if there is an option that the TVC is delivered sprayed in white polyurethane colour. i know this sounds silly and yes it is, but WAF is something that lots of us audiophiles has to put into account.

nick?

[randytsuch]

By the way, do you have a URL for Tubelover's DAC?

I forgot to mention that it is a parallel TDA1541A dac with tube output stage that can use  a 6c45 SE, 6DJ8 SRPP or AD844 opamp. The kit came with all parts needed except 18V transformers, chassis, and rca's.

Tubelover's new website is working, but there isn't any info up yet. Here is the original thread(45 pages) with pictures of his version 1 & 2 PCB's plus complete circuit and parts description.

Believe it or not, I spent all of tonight searching for the dac board and cannot find the damn thing anywhere in my hobby room. I can't find the original box, either. Oddly, I keep everything, religiously, but there's nothing here!!! This is driving me crazy! The only thing I can think is that my EE brother was real interested in it last Christmas when he was down here. Maybe I gave it to him because it wasn't getting used.

I threw out a bunch of empty boxes 6 months ago, I hope it wasn't in one of them.

Damned shame because it was the heaviest and best looking pcb board I have ever laid hands on. The dac allowed for all kinds of experimentation.

Now I'm wondering what else I've lost.

Don't feel bad, I have lost some stuff too.  I have tried to improve my orginazation of materials, for instance now I "kit" parts, keeping all the parts bought for a specific project in a labeled box, or large ziplock.  But, stuff gets moved around, and sometimes lost.

Randy

[GHM]

Well another one bites the dust! I have a good friend..the one who got me into this crazy hobby from the start, whose been out of town for several months now. He's basically missed this Promitheus saga.

Today he ask me to bring over the little red box for a listen. His two channel consists of an Arcam FMJ DV27 as a source, Classe ca300 amplifier, the Electric Minimax as the preamp and EminentTech LFT-8s for speakers. I suppose you can guess where this is going. We dropped in the Promitheus in place of the EE to hear if the change might be for the better or worst with his system.

In short he was absolutely floored!! We spent several hours today listening to this system. In between listens he had me to go on-line and order him a Promitheus TVC. I'm guessing the volume pot is the biggest culprit for the differences in sound we heard today.

I have the same Noble pot on my Audio Sector integrated. This morning I set every thing back up using the built in volume control and sat down for a listen.

The pot made the soundscape seem flat by comparison of the TVC. In fact I find it hard to listen without the TVC in the system now. Going against the school of thought that simpler is better, having added the extra set of cables along with the extra component (TVC) in the chain was more transparent than the built in Noble pot. The depth, transient attack and bass all went out the window with the Noble pot in the chain! I mean gone in a big way!

My buddy ask me to leave the Promitheus in his system so he could listen too it more over the weekend. Before I left his house today, he did make it clear that the EE minimax was going up for sale ! So I'll be posting it on AC and Audiogon for perspective buyers very soon. Anyone looking for a mint condition EE Minimax on the cheap let me know.

I also turned him on to the Paradesia NON OS Dac..this is where the proceeds from the EE MiniMax will go. My only regret is now I'll just have to wait till next week to listen to my system again. I can't listen to the noble pot any more!

[akmal00]

Nicholas,

inquiring minds want to know about:
1.  hybrid amp. is this one enclosure or two separate enclosure amp to play stereo
2.  CD transport to match your DAC at around 320-350 USD. after 7 years dispose of transport when laser
expires.  if your DAC is as good as your TVC nothing can stop you.
3.  need picture of your power energizer.

Hi there everyone, I am new to this circle but just to share my experience when I had the opportunity to listen to the Promitheus TVC and the new hybrid monoblocks. This new hybrid monoblocks are separate chassis with two independent power supply. You would need two power cords.

Listening was through an Oracle CD 550 player, the said amplification driving a pair of Diapason Karis spks. The cabling was a USD 1000 custom made IC's, Audio Note's IC's between the TVC and the power amps. The energizer was there as well. Speaker cables was from Krell.

The hybrid amps were very sensitive to type of support and the wooden cones. However from my discussion with Nick the amp design is still not finalised. There were an initial hum problem due to ?ground loop. But that was corrected immediately by Nick.

Short to say the result was magic. I am personally waiting for the revised model. Daily hoping for it to come out. The TVC was not the reference.

The phono pre-amp is great as well. I have been using it for three months. Much better than the Dynavector P-75. You can adjust the gain for almost any type of catridge or amps. Makes average system into good ones.

[GHM]

Hello akmal00 and welcome to AudioCircle! Nick also informed me of the new monos and said he needed to do some fine tuning with them. Due to the use of no negative feedback..the bass was a little loose from his description. He also mentioned a slight hum. I've bugged him about these hybrids for a while now. Hopefully he'll get the bugs out so I can try them !