Promitheus TVC passive preamp anyone?

PromitheusAudio · « **Reply #1840 on:** 9 Jun 2007, 05:38 am »

Randy
Can you send me some photos of the unit so that i can see what when wrong

ROnW
send you an email already
Been busy with the shifting so now i catching up on the mail

NewBuyer · « **Reply #1841 on:** 9 Jun 2007, 06:45 am »

Quote from: anubisgrau on 7 Jun 2007, 10:44 pm

...i was a witness of putting promitheus on oscilloscope and measuring its response as well as ringing behaviour

i was a bit surprised to find that it has an early resonance point at 27.5 khz. i think this has to be moved further way up from the audible range...

it has -3db at 5-6hz, it's flat until 10k when surprisingly early it starts to rise.

27.5 khz resonance is just too close to the audible range that i am confident it affects the sound in some way, though i can't say how right now...

Does anybody here know, if the effect if this resonance would be in any way audible? Just curious...

jonners · « **Reply #1842 on:** 9 Jun 2007, 08:09 am »

Quote from: Randy on 9 Jun 2007, 01:44 am

Can anybody tell me what's wrong with my TVC? I finally took the cover off to take a look and could not find any obvious damage, loose wires, etc. Hooked it back up and it seemed fine. (Kept the cover off.) Now it seems to be fading away in volume again. There is no added gain at all in the last seven or eight clicks. Sounds fine, but I need more volume and can't get it.

Are you sure that there's not a problem with your source or amp? There's not much that could go wrong with a TVC apart from wires coming loose or a faulty switch.

Oscillate · « **Reply #1843 on:** 9 Jun 2007, 08:41 am »

"Hey Oscillate, did you get your Promi gear, yet? If so how do you like it?"

Not yet sir ...with reasons. I'm pretty sure that Nicholas was going to build and then send the entire system at the same time. Since he had not yet started building the amplifier, I asked him if I could upgrade to a SET tube amp. So specifics and arrangements are being made toward that. Also, I'm moving across the country in few weeks and asked Nicholas if he could delay shipping until I have a new residence. Hopefully by sometime in late July, everything will be in house?

I still intend to do a complete review after it's all up and running.

rollo · « **Reply #1844 on:** 9 Jun 2007, 02:21 pm »

Quote from: Randy on 9 Jun 2007, 01:49 am

And it seems to be fading away even more as I listen. Strange.

Randy,

Strange indeed. Never heard this one before. Unless your CDP is 1V or less this should not occur. How about the input sensitivity of your amp. Is it less than 1V or higher?
Other than those two areas of concern I am clueless. Its time for Sir Nicholas to intervene.

rollo

Randy · « **Reply #1845 on:** 9 Jun 2007, 02:48 pm »

Nick and Rollo - I don't have digital photo capacity, so can't send a photo to you, Nick. Last night and a few weeks ago when this first occurrred there was no change in volume for the last seven or so clicks, and actually decreased the last two clicks. When I first hooked it up again yesterday, all seemed fine, but the problem soon came back. This morning it seems okay, so go figure. Whatever it is, I don't think it is a CDP or amp problem as I have had the TVC since last October & it worked beautifully for the next eight months. Recently there's been one change, my Levinson CDP died (power supply, apparently) about a month ago, so I have had to play a cheap Sony since, but it had plenty of slam and volume until the recent problem. Will see if the problem comes back again.

rollo · « **Reply #1846 on:** 9 Jun 2007, 03:03 pm »

Quote from: Randy on 9 Jun 2007, 02:48 pm

Nick and Rollo - I don't have digital photo capacity, so can't send a photo to you, Nick. Last night and a few weeks ago when this first occurred there was no change in volume for the last seven or so clicks, and actually decreased the last two clicks. When I first hooked it up again yesterday, all seemed fine, but the problem soon came back. This morning it seems okay, so go figure. Whatever it is, I don't think it is a CDP or amp problem as I have had the TVC since last October & it worked beautifully for the next eight months. Recently there's been one change, my Levinson CDP died (power supply, apparently) about a month ago, so I have had to play a cheap Sony since, but it had plenty of slam and volume until the recent problem. Will see if the problem comes back again.

Randy,

Well, just trying to narrow things down. Not blaming your components. Do you have a selector switch? Check all solder joints to see if one is loose or cold soldered. This is puzzling at best. I believe Sir Nicholas needs to delve into this issue a bit further. This is beyond my scope.
Hopefully it is something simple and all will be well. Good luck.

rollo

Randy · « **Reply #1847 on:** 9 Jun 2007, 03:30 pm »

Rollo,
I have a source selecton switch, a dial. Is that what you mean? I don't have the toggle switch I've seen on some more recent models. Mine's an early second generation TVC. I am used to a 4.4 output voltage on my CDP. The one now is probably around 2.0, but I didn't notice any problem with volume until I was using the 2.0 player for several weeks. I probably need to get a new player and see what happens with the new one.

rollo · « **Reply #1848 on:** 11 Jun 2007, 02:04 pm »

Well today is the day. Leaving to visit Nicholas for 17 days. Going to see what he has up his sleeve for the future. According to Nicholas we are in for some surprises with the new Tranformers. The prototype of the GM70 amp is ready for a listen as well as the DAC, phonostage and Big Momma TVC.
I may have some great news when I return.
See ya all, will post from Malaysia if I can.

rollo

dgotlse · « **Reply #1849 on:** 11 Jun 2007, 02:25 pm »

Quote from: rollo on 11 Jun 2007, 02:04 pm

Leaving to visit Nicholas for 17 days.

Hey Rollo, leave him time enough for building our gear

Enjoy your stay over there and keep us informed of what's going on in Nick's laboratory.

Randy · « **Reply #1850 on:** 11 Jun 2007, 03:04 pm »

Rollo,
If you are into classical, Malaysia has a great symphony orchestra. Catch a concert if you can.

Say · « **Reply #1851 on:** 11 Jun 2007, 04:30 pm »

Be sure to take some spy shots, Rollo, before Automobile and Car and Driver do. lol!

My TVC is sounding awsome. Just when you think you've got it good out comes Nick with his, soon to be released, super TVC. Darn thing with this company is that so many new items are created that it's easy to get behind the curve. Oh well! "Enjoy what we've already got" is my motto for the day.

Gaara · « **Reply #1852 on:** 11 Jun 2007, 06:20 pm »

Anyone get the June 2007 Stereophile yet? I was flipping through and saw a picture I didn't think I would ever see in there. "Promitheus unchained! Meticulous workmanship, beautiful sound. Just don't turn it topsy turvy". First the OPPO, then the Squeezebox, now TVCs they really are picking up on the internet hype.

Jared

dgotlse · « **Reply #1853 on:** 11 Jun 2007, 06:24 pm »

Quote from: Gaara on 11 Jun 2007, 06:20 pm

Anyone get the June 2007 Stereophile yet? I was flipping through and saw a picture I didn't think I would ever see in there. "Promitheus unchained! Meticulous workmanship, beautiful sound. Just don't turn it topsy turvy". First the OPPO, then the Squeezebox, now TVCs they really are picking up on the internet hype.

Jared

Which page? I haven't seen it yet.

Gaara · « **Reply #1854 on:** 11 Jun 2007, 06:31 pm »

Pg 19-23 Sam's Space. Not a formal review but a long discussion on TVCs, Promitheus, Nic, and some comments on the sound.

dgotlse · « **Reply #1855 on:** 11 Jun 2007, 06:34 pm »

Thanks

Early B. · « **Reply #1856 on:** 11 Jun 2007, 08:19 pm »

Quote from: Gaara on 11 Jun 2007, 06:20 pm

Anyone get the June 2007 Stereophile yet?

Just read it. Great review. In fact, the reviewer mentioned twice that he was buying the TVC. What else is there to say?

Nice job, Nic.

dgotlse · « **Reply #1857 on:** 11 Jun 2007, 08:38 pm »

There's probably something wrong with me, I can't find it.

In my electronic issue, Sam's pages start on page 27 with an Harbeth speaker review and ends on page 31 with a Ray Samuels headphone amplifier.

Are you both sure that is June's issue ?

Early B. · « **Reply #1858 on:** 11 Jun 2007, 08:43 pm »

Quote from: dgotlse on 11 Jun 2007, 08:38 pm

Are you both sure that is June's issue ?

It's actually the July 2007 issue.

dgotlse · « **Reply #1859 on:** 11 Jun 2007, 08:44 pm »

Should receive it soon then.