Promitheus TVC Preamp

Interesting... thanks for the link.

Here’s another manufacturer who makes preamps with “Transformer volume control”. Quite popular among purist audiophiles.
http://www.bentaudio.com/index2.html

Squarewave,
Just received the TVC from Promitheus,have kept it for cooking with a tuner.Once properly burned in(100 hrs) will do a critical listening with a cdp,and report the findings.Already see a lush sound coming after 24 hours..Already see signs of lush/lifelike sound.
Keep tuned.
Thanks.

hifinovice1 schrieb:

..Already see signs of lush/lifelike sound. Keep tuned. Thanks.

err......hifinovice1,

if something has a lush sound, it is generally not thought of having a life-like sound!! one would say that it has a lush sound.
Generally speaking lush sound is used derogatorily & it usually indicates a unit that has "coloured" sound wherein every part of the audio spectrum is over-emphasized.
Examples from yester years are C-J tube gear & Audio Research tube preamps.


So, is the Promitheus TVC preamp lush or life-like?
(from what I've read on the forums it seems to be more life-like??)

it neutrality is what i too have heard praised. maybe the sound has more body now..thats what he might mean by lush. ( after listening to tinny mp3s anything with body is going to sound lush )

aside: lush bodies although are not just a preference in audio

Which model did you pick up ?

You are right bombaywalla and Arj!!
(I have to be more careful with adjectives,each word seems to have a connotation in audio )
I meant lifelike with more body,transparency and blacker blackgrounds.
I picked up basic TVC(revision3),4 unbalanced inputs.
This weekend(hopefully) will do a critical listening,and post the outcome.
(Seems to be picky about closing unused RCA's with plugs)

do you get a higher volume when the RCAs are closed ?

I replaced the DACT attenuator with a TVC recently. Huge improvement in Dynamics and a more defined (more open and three dimensional) stage.

However, i had to tweak my preamp and DAC to reduce the gain else-where (most TVC seems to be designed for passive operation only).

For passive operations, no attenuator can be a competion for a TVC !!.

Unfortunately, a good TVC will also burns a much deeper hole in your pocket

Amp_Nut,

Unlike using resistor in signal patch, the transformer will provide more stable impedance across the spectrum. Which i think is the key for this .... I feel, it's just the opposite of what you had mentioned on the DAC thread

Regards
Siva.

Arj,
Volume remains same,no change,if you close unused RCA's or not.
Siva:I'm struggling with a slight hum when cdp is connected,with tuner absolutely no hum.
Tried moving TVC away from active components,plugging RCA'a but still an issue.
What's your experience?
Thanks.

If the CDP is a 2 pin mains plug, flip it at the Wall socket end ( ie interchange Live & Neutral)...

Could work... worth a try.

hifinovice1 schrieb:

Arj, Volume remains same,no change,if you close unused RCA's or not. Siva:I'm struggling with a slight hum when cdp is connected,with tuner absolutely no hum. Tried moving TVC away from active components,plugging RCA'a but still an issue. What's your experience? Thanks.

It probably due to the way signal ground is connected in your preamp. Please check with your manufacturer....may be you need to remove (or connect) the "signal ground" connection to the chassis on your preamp.

Also try to remove all other connections from the preamp (except the CD player and power amp)...you might be able to atleast isolate the problem.

Regards
Siva.

Thanks Siva,
The problem was with S-video connection.If you take it out it's dead quiet.Been working by adding a ground loop to various places to see,why it's happening.
Listened over the weekend and it's jaw dropping transparency all the way,better dynamics and better base.
You feel as if performers are in the room,it's that transparent,a different experience altogether.
I would say it is biggest bang for the buck,by far the best audio tweak.
And this is connected to Int. Amp,I think if you have no volume pot further(power amp)it might be still better.

Hello hifinovice1

A few questions...

Where are you geographically located ? Asking to explore the possibility of visiting and hearing ...

How did you import the unit ? By courier, as a personal import ?

What was the Unit Cost ? ( With Courier Charge )

What was the Customs Duty ?

How many positions are there on the volume control ?

Thanks for your feedback

hifinovice1 schrieb:

Thanks Siva, The problem was with S-video connection.If you take it out it's dead quiet.Been working by adding a ground loop to various places to see,why it's happening. Listened over the weekend and it's jaw dropping transparency all the way,better dynamics and better base. You feel as if performers are in the room,it's that transparent,a different experience altogether. I would say it is biggest bang for the buck,by far the best audio tweak. And this is connected to Int. Amp,I think if you have no volume pot further(power amp)it might be still better.

What integrated do you have ? Isn’t there a way to bypass the preamp and volume pot in the amp ?
If you can bypass it or better still, use a power amp, the sound will be far better.

hifinovice1 schrieb:

Thanks Siva, The problem was with S-video connection.If you take it out it's dead quiet.Been working by adding a ground loop to various places to see,why it's happening. Listened over the weekend and it's jaw dropping transparency all the way,better dynamics and better base. You feel as if performers are in the room,it's that transparent,a different experience altogether. I would say it is biggest bang for the buck,by far the best audio tweak. And this is connected to Int. Amp,I think if you have no volume pot further(power amp)it might be still better.

Hi-End Audio is a lot simpler than we would like to believe. You've made a very good buy.

For your ground loop problem, try to get some transformer. Contact Prithvi, i think he might have some in stock.

Regards
Siva.

Amp Nut,
I'm currently in US.
This unit costs 400 USD,shipping from Malaysia included(no duties).Talk/email Nick Chua,he is a great person,I do not see any issues importing to India.Ask him if he can declare it as a personal gift (In fact with duties also it's worth it,it's that good).It has 24 positions with 48 db attenuation)

Square wave:I'm using Magnum Audio 170 SE integrated(75Wx2),into Tyler acoustics-Tylo monitor speakers.The Magnum does not have pre bypass switch,contemplating a good power amp.in the long run,with TVC as pre.

Siva:What's this ground loop transfomer called?
Thanks.

Square wave,
In fact the Magnum Audio has a monitor input and a monitor switch,I will try using that,and see if it really bypasses the Magnum's volume control pot.
In that case my problem of removing the resistive pot in the signal will be solved easily .(more transparency?)
Thanks for asking me to check that..
Will report on the findings,stay tuned.

You are in the US ? Awesome ! Since you don’t have a mind block against small manufacturers for whom fidelity is still the first priority (your choice of Tyler acoustics / Promitheus over more mainstream brands suggests this…), there are a number of fine amp manufacturers out there who give fantastic value for the buck.
You will see a serious improvement once you bypass that preamp in the integrated.

square wave,
You are right,this place has so much going on.
Yesterday night I tried using the monitor input,on the magnum integrated amp, it bypassed the input selector switch and not the volume pot.But still I could detect a definite improvement.
So I think,your prediction that there is lot of potential left for improvement until that second pot is removed from the signal path,sound correct to me.

Nicholas indicated to me that he recently sold one TVC to India,without any problems.
And he can declare it's value as 100 USD for less custom's hassles.Sounds good to me,what do you think?

The humming issue,while connecting a S-video has been eliminated by removing the ground pin going to int.amp.
Thanks.

hifinovice1 schrieb:

The humming issue,while connecting a S-video has been eliminated by removing the ground pin going to int.amp. Thanks.

It seems - "Creating one problem to solve another problem" - is the forte of audiophiles !!

hifinovice1 schrieb:

Has anyone used/heard this? http://www.promitheusaudio.com/frontpage.htmlhttp://www.promitheusaudio.com/frontpage.html Seems a huge hit with audiocircle members with a thread over 100,000 views... How to configure this for an integrated amp,will it benefit? I exchnaged mail with Nicholas,the designer from Malaysia and he said some people are using it with an int amp. and it helps by keeping volume at 3/4 or max on int amp and controlling the volume from TVC.(Will the ouptput impedence a problem in that case?) Thanks.

hifinovice1,
You mention keeping the volume at 3/4 or max on integrated after connecting the TVC. I thought the integrated volume control did not matter, since you would be bypassing the pre-amp in your integrated. Which integrated do you have?
Also for the hum, some people got rid of it by stuffing the internals of the TVC with cotton or glass-wool. Instead of removing the ground-pin going to integrated, try this first. Another "try" is to isolate the TVC away from the other electronics.
I have requested Nicholas to stuff mine with cotton. Also, have requested him to put the Elma controller - of course at extra cost. Mine is the ref C-core version. The Signature version is too expensive for me.
What are the "numbers" for the power amp in your integrated? My NAD has the following: 770 mV / 20k ohms / 470 pF. I checked with Nicholas and he said that the TVC will work fine, as the input sensitivity is high. Some one on Audiogon commented that the impedance is a bit lower (20k ohm instead of 100k ohm). I just hope that the TVC and my integrated works. Waiting in anticipation for my TVC to arrive

Hi Milpai,
Could you please check your private messages? Someone wants to talk to you about the TVC.

Thanx
sq_wave

Sq_wave,
Saw your message. Replied to you.

Hey Milpai,
Did you like what you heard using TVC? I hope you are enjoying it.
Thanks.

Hi hifinovice,
I got my Reference C-Core about a month back. I have posted my findings here: http://www.audiocircle.com/circles/index.php?topic=67786.0.

I am still zapped by the strength of this component. I feel that EVERY integrated amp owner with MAIN IN should use this TVC just to see how good his/her integrated performs as a power amp. The TVC is simply removed itself from the music path and makes everything so 3D!!!

Square_wave, did the other gentleman I contacted, purchase the TVC? Tried to contact him again, but did not get a response.

Thanks

I wonder if anoyone's compared the standard and reference models.

milpai schrieb:

Hi hifinovice, I got my Reference C-Core about a month back. I have posted my findings here: http://www.audiocircle.com/circles/index.php?topic=67786.0. I am still zapped by the strength of this component. I feel that EVERY integrated amp owner with MAIN IN should use this TVC just to see how good his/her integrated performs as a power amp. The TVC is simply removed itself from the music path and makes everything so 3D!!! Square_wave, did the other gentleman I contacted, purchase the TVC? Tried to contact him again, but did not get a response. Thanks

Milpai,
Sorry. Never saw this post. He picked up a leben integrated hence decided not to go with the pre/power route.

square_wave schrieb:

milpai schrieb: Hi hifinovice, I got my Reference C-Core about a month back. I have posted my findings here: http://www.audiocircle.com/circles/index.php?topic=67786.0. I am still zapped by the strength of this component. I feel that EVERY integrated amp owner with MAIN IN should use this TVC just to see how good his/her integrated performs as a power amp. The TVC is simply removed itself from the music path and makes everything so 3D!!! Square_wave, did the other gentleman I contacted, purchase the TVC? Tried to contact him again, but did not get a response. Thanks Milpai, Sorry. Never saw this post. He picked up a leben integrated hence decided not to go with the pre/power route.

Not a problem square_wave. I am sure he is having a great time!! Yes, this forum is a bit slow. When I left India in Jan 2002 hi-fi was limited to Heera Panna and some small time black-markets. I am glad that the market has opened up so much and people there have access to the latest and greatest audio equipments. Also glad that we now have forums dedicated to our great hobby.

Restarting an old thread...

I recently acquired an used Promitheus TVC. When I plugged it to my setup I got a loud hum in one channel. I tried plugging all inputs to valid sources but the problem remained. I tried it with NAD 902 power and NAD 320's line in as well as power in with the same result

My setup (all stacked close to each other in 3 levels include, a CDP, AVR, DAC, power amp, integrated amp, TT, Phonostage, Tape deck, media player, hard disk...

Is the close proximity to these electronics causing the problem? I will try placing the TVC as far as possible from these today.

Is there any other thing that I could try?

If nothing else works, I will try stuffing cottonwool into the TVC box.

Move it away from your equipment stack, (laterally) and see if the hum is eliminated or atleast reduced.

If you still have a Hum, try swapping the left and right Input and the left and right outputs.

If the Hum now appears in the other channel, you have a defective TVC. It could be something as minor as a shield wire / Gnd connection in the TVC having become undone....

( Stuffing Cotton will not help at all .... )

Thanks Amp Nut,

I did try that yesterday. Moved the TVC as far as possible from the other electronics (about 3ft). The hum reduced but it was still there. It's more prominent on certain volume levels. I did not interchange the connections but earlier when I had done that, the hum had moved to other speaker.

Probably the TVC connections have been dislodged during transit, we all know how the courier guys handle our precious cargo.

But if the distance is the issue then I have a real problem, how do I maintain a setup with one component to be kept as far as possible from the others?

soulforged schrieb:

Thanks Amp Nut, I did not interchange the connections but earlier when I had done that, the hum had moved to other speaker.

you have a defective TVC. most probably one or more wires have broken off from the solder joint. Usually not an issue at all. You need to open the top lid & take a very good look inside to see which of the wire(s) is loose & re-solder. Give a gentle tug to all other wires to ensure that they are secure & not about to break loose.

soulforged schrieb:

But if the distance is the issue then I have a real problem, how do I maintain a setup with one component to be kept as far as possible from the others? :(

distance should no longer be your issue once you have stated the underlines & bold text. TVCs can be kept in the same rack & at close proximity to other equipment without any hum issues. It's been done every single day world-wide.....

I opened the box this weekend. Saw no wires hanging obviously loose. There were a bunch of very fine strands running from the volume pot and input selector to what looked like two transformers. Just rearranged them and put the top back on. Tightened the screws holding down the transformers and hooked it up...and voila! it performed silently...magic!!!

Just heard a couple of songs...will hook it up properly to all my sources and check it again.

Thanks for all your advice.

PS. pardon my naive descriptions of the technical thingamigiks I saw in the box...