[lonewolfny42]

Hey Chris..I dropped in some fresh batteries. The remote works fine.

Thanks Gymane....I hadn't check it....now you can sit back down and relax.... ...thanks.

[JLM]

I can go days without touching the volume control.  I listen at life-like levels or below as the mood strikes me.  If the phone rings I hit the pause control.  But listening in the man cave does help.

Besides, for every 10,000 times I get up to adjust the volume is one less time I have to go to the gym to workout.   

[Valvelover]

Hello everybody ,
I' m new in this forum, and writing to sharing with you the impressions about my new Promitheus audio TVC.
I'm from Italy and have purchased my TVC from Nickolas three week ago.
Before everything I have to say that this is the greatest object for audio that I have never buyed!!!
I want to say to Nickolac a big thank you for this present.. yes a present is this wonderful sounding TVC at only $ 340(wordwide shipping included)!!
This past week-end with some friends of mine that have others TVC as MFA(copper version and silver version), Django, Antique sound lab and Sonic Euphoria, we have listened my Promitheus TVC vs the others and...my Promitheus TVC was a big SURPRISE for us!!
Only the MFA silver version has proved to be the nearest in sound quality to the Promitheus TVC but ATTENTION PLEASE it cost in Italy more than 4000 euros and my Promitheus TVC costs only 340 USD(w.s.i.), do you understood what's the diference? A lot of money to buy MFA silver version that's no more no less in performances than Promitheus TVC  !!!
I have no words to describe the ammount of sonic beauties that this little jewel introduces in the sound system perhaps because it is so transparent and open sounding that you'll ear only your preferred music troght it.
I think that everyone should have a Promitheus audio TVC at home to comprise the right value of every system component bought.
In the end I can assure that Nick from Promitheus audio has hit the target.. "Bring the hi end music to the masses".
Cheers,
Musiclover

[GHM]

Thanks Valvelover for your impressions and welcome to Audiocircle. It's good to know others around the world are enjoying the little Malaysian box.

Good listening!

[Valvelover]

Thanks Valvelover for your impressions and welcome to Audiocircle. It's good to know others around the world are enjoying the little Malaysian box.

Good listening!

Thank you GHM and good listening to all 

[anubisgrau]

Hello everybody ,
I' m new in this forum, and writing to sharing with you the impressions about my new Promitheus audio TVC.
I'm from Italy and have purchased my TVC from Nickolas three week ago.
Before everything I have to say that this is the greatest object for audio that I have never buyed!!!
I want to say to Nickolac a big thank you for this present.. yes a present is this wonderful sounding TVC at only $ 340(wordwide shipping included)!!
This past week-end with some friends of mine that have others TVC as MFA(copper version and silver version), Django, Antique sound lab and Sonic Euphoria, we have listened my Promitheus TVC vs the others and...my Promitheus TVC was a big SURPRISE for us!!
Only the MFA silver version has proved to be the nearest in sound quality to the Promitheus TVC but ATTENTION PLEASE it cost in Italy more than 4000 euros and my Promitheus TVC costs only 340 USD(w.s.i.), do you understood what's the diference? A lot of money to buy MFA silver version that's no more no less in performances than Promitheus TVC  !!!
I have no words to describe the ammount of sonic beauties that this little jewel introduces in the sound system perhaps because it is so transparent and open sounding that you'll ear only your preferred music troght it.
I think that everyone should have a Promitheus audio TVC at home to comprise the right value of every system component bought.
In the end I can assure that Nick from Promitheus audio has hit the target.. "Bring the hi end music to the masses".
Cheers,
Musiclover

Thanks Valvelover - Musiclover

Excellent review - it is a direct TVC competition where Promitheus is going to prove itself. If I may add, TVCs are not for everyone and for every system, and it would be really great to read more reviews and test how Promitheus would compare with some of the best active preamps out there on the market.

For example, my current benchmark preamp is Pass Labs X2.5 because it is one of the seldom active SS designs that marries realism, transparency and musicality. Most of the other big names I have tried usually excells in one field and fails in another and X2.5 is just a great allrounded.

However it costs 3.900$.

If Promitheus would be able to hold it's own against it......whoooahhhh, maybe i should stop dreaming.

But still, if any of the current users tested it againt some of the big active beasts out there, it would be great to hear the score.

And yes, I got slowly adjusted to the idea of living with no remote.

[GHM]

Thanks Valvelover - Musiclover

Excellent review - it is a direct TVC competition where Promitheus is going to prove itself. If I may add, TVCs are not for everyone and for every system, and it would be really great to read more reviews and test how Promitheus would compare with some of the best active preamps out there on the market.

For example, my current benchmark preamp is Pass Labs X2.5 because it is one of the seldom active SS designs that marries realism, transparency and musicality. Most of the other big names I have tried usually excells in one field and fails in another and X2.5 is just a great allrounded.

However it costs 3.900$.

If Promitheus would be able to hold it's own against it......whoooahhhh, maybe i should stop dreaming.

But still, if any of the current users tested it against some of the big active beasts out there, it would be great to hear the score.

And yes, I got slowly adjusted to the idea of living with no remote.

Hopefully the reviewer of 6moons will do some good comparisons. Correct me if I'm wrong.. Have you heard any TVCs before?..I didn't think you had. I believe this is the only way for you to ever know if it competes for your taste or not.

 You can read the reviews till your eyes hurt...you must eventually find out for yourself. I can tell you cost isn't a real factor here. If something sounds great to your ears..that's what matters most.

Good listening

[oliverlim]

I just recieved my unit on saturday and immediately started burning in the unit. 
The build quality of the unit is fantastic. For a little over US$300, this is a really
good deal. Not to mention the fact that I really like wood!  :p

Anyway initially I was a little apprehensive about getting this unit. I have a mid-fi
setup and wanted a transparent preamp for stereo listening instead of using my
Rotel RSP-1068 preprocessor. It does sound harsh at times but does really well with
HT. The initial listening session I did at the beginning after doing a level match
was jsut basically both sounded different. One was from my modifed
Pioneer DV989 analog out to the rotel then to my Odyssey amp to my Thiels 2.4.
The other was from the Pioneer to the Promitheus to my Odyssey to my thiels.
Oh did I mention why I was apprehensive? I am using a 7.5 meters interconnect
from my preamp to my Amps.  I am using a low capacitance Canare L5C with their
clamp type RCA which I love. Defintely did not sound that there was any loss in bass or highs
from the TVC.

I finally sat down and did some listening yesterday after the unit had been running for like 50 hours.
I have to say that I am still speechless. The highs which at times sounded harsh when driven through my Rotels were detailed yet smooth. The mids almost had that tube like liquidity. Bass was all there. Impact, deep.  And the transcient effect which was the main reason I liked Thiels was being delivered in spades. The drum beats, guitar strums, all were just so there...... Everything in the music just sounded so effortless and right.

I then decided to get scientific to see if it had changed anything to the frequency response to sound so different.  I had measured some tube pre and amps and they defintely did change the FR somewhat most of the time.  I brought up my Behringer EM8000 mic and ran REQW which has a sweep measurement.

It was interesting what it showed. That the TVC is as transparant as you can get and it does not
skew the FR one bit.  Plus, it also shows that as a passive pre, it can drive long interconnects as well
which show that system matching should not be a problem in almost all cases.

The measurement was done with a mic at my listening position.  The red one is via a sweep 20hz to 20khz to my rotel via bypass mode(rotel acting as a pre only) , then output via the rotel to the TVC input and then connected to my odyssey amp.  Using a 1 meter canare interconnect between the Rotel and the TVC.  The red one is the same sweep via the rotel direct to the amp.



As you can see it is similar.  There are always 1-2db variations even withthe same sweep every single time you do it. So as far as I am concern it is the same! Note that there is about a 2db loss. So
I had to turn up the rotel volume 2db to get the graph to align.  I guess the extra interconnect resulted in insertion loss which is to be expected.  So no loss of bass and no loss of highs.  But yet sounds better. sometimes it is difficult to explain why it can sound so different?  :p

I think anyone who is worried about system matching should still give this unit a try.  With the 30 days money back, what do you have to lose? I believe my situation has shown that this preamp is very system friendly.

Thanks Nicholas for bring this unit to us!

Oliver

[gme109]

Just wondering if anyone has tried the Promitheus interconnect? It seems to make sense, that if you like the sound of the preamp, which is wired with the same wire as the ic, the ic would not add or take anything away from that sound. Is that in fact the case, for those who haved compared the Promitheus ic to different brands?

[Steve Eddy]

By the way, is this the same Prometheus Audio that makes turntables and turntable stands or is it some other Prometheus Audio? Reason I ask is if I go to prometheusaudio.com, I can't find so much as a mention of any TVCs, interconnects, etc.

se

[TheChairGuy]

http://www.promitheusaudio.com/

one letter makes all the difference....

[Steve Eddy]

http://www.promitheusaudio.com/

one letter makes all the difference....

D'oh! 

Thanks!

se

[xsb7244]

Nicholas, when is your DAC coming out?

[Steve Eddy]

Just a couple of comments with regard to some statements made on their FAQ page:

Unlike resistive elements where the output impedance is set by the resistive element (potentiometer or step attenuator form with resistors) i.e. 10K pot will have an output impedance of 5K , 50 K pot will have an output impedance of 25K.

This is incorrect. The ouput resistance (can't really say it's an impedance because a pot's not a reactive device) of a 10k pot will be 2.5k, not 5k, and a 50k pot will be 12.5k, not 25k. Also, this is the worst case scenario where the pot's at its midway point resistively. Above and below this point it will become lower and lower.

And this:

THE TVC is essentially an electronic gearbox that operates without wasting significant energy. Potentiometers and stepped attenuators adjust the signal level by literally turning the excess signal into heat.

I've seen this elsewhere and I've always had problems with it.

In line level interfaces such as between a CD player and a preamp or amplifier, we're not interested in transfering maximum power, we're interested in trasnferring maximum voltage. That's why we try to keep source impedances low and input impedances high. If we were trying to transfer maximum power, then we'd want source and load impedances to be identical.

And whether using a TVC or a pot, ALL of the signal is ultimately turned into heat. The input impedance of a preamp or amp is usually in the form of a shunt resistor. Virtually all of the current coming from the source is flowing through that resistor and in a resistor, all power is consumed as heat. All that the actual input circuit cares about is the voltage dropped across that resistor, not how much power it's consuming as heat.

As I said above, we're interested in transfering maximum voltage from one component to the other, and what a potentiometer does is act as a voltage divider. The voltage from the source is placed across the end-to-end resistance of the pot and depending on the output voltage and the end-to-end resistance of the pot, a given amount of current will flow through it.

If we have a 2 volt output, and a 10k pot, about 200 microamps will flow through the pot. As per Ohm's Law, the voltage across a resistance is the current flowing through the resistance times the value of the resistance, or E=IxR.

So, if we adjust the pot to its midway point, the output is being taken across 5k ohms (half the pot's 10k ohm end-to-end resistance). Knowing how much current is flowing through the pot, we can calculate what the voltage will be at the output. In this case it will be 200 microamps times 5,000 ohms, or 1 volt. That's half our original 2 volt input so we can say that the pot is attenuating the signal by 6dB (20 x log (Vout/Vin)).

Anyway, point being that the notion that the reason a TVC sounds better than a pot is because the pot is "turning excess signal into heat" is just silly. That's not to say that pots are pefect. They're not. They do have the issue of their output resistance which can be problematic with regard to the capacitance of longer runs of cable.

And I don't want anyone to construe any of this to be any sort of criticism of the Promitheus TVC. It's not, nor is it intended to be. It's that anyone who has an interest in understanding what's going on vis a vis TVCs and potentiometers isn't well served when they're told that potentiometers are bad because they "turn excess signal into heat."

se

[NewBuyer]

...if you like the sound of the preamp, which is wired with the same wire as the ic, ...

Just noting that I believe the new version 3 TVC trannies are now wound with copper.

...the notion that the reason a TVC sounds better than a pot is because the pot is "turning excess signal into heat" is just silly... anyone who has an interest in understanding what's going on vis a vis TVCs and potentiometers isn't well served when they're told that potentiometers are bad because they "turn excess signal into heat."

Thanks Steve! So if you don't feel the above is a good explanation, what explanation please would you personally give instead? Just curious, as I am always learning in this hobby...

[GHM]

Wow!! Oliver thanks for the great review with the graphs. 

Steve very educational post. I've learned a lot since this thread began about TVCs and other passives. Your knowledge seems vast about this subject. 
Your feedback is most welcomed!! I think I as well as others are here to learn. You have been a great help and always welcomed to post here.

I see you've caught the attention of 6moons in a recent review. You have a very interesting design using the Transformers(posted earlier in this thread).
I look forward to seeing the finished product! I'm always open to the possiblities of good sound.  It doesn't matter where or who it's from.

All the Best

[NewBuyer]

Hey just noticed that at the Promitheus Audio website, two new products are now announced - a Reference Version TVC, and a Power Energizer product. Looks interesting!

[GHM]

Hey just noticed that at the Promitheus Audio website, two new products are now announced - a Reference Version TVC, and a Power Energizer product. Looks interesting!

Holy smokes Newbuyer..I hadn't seen this . Nick seems to be a very busy man these days! Looks like I'll have to pester him about this Reference version!

[Steve Eddy]

Thanks Steve! So if you don't feel the above is a good explanation, what explanation please would you personally give instead? Just curious, as I am always learning in this hobby...

Well, personally I think the whole idea of trying to explain why something "sounds good" is for the most part a bit silly.

Sounds good to whom? Me? You? Someone else? What sounds good to me, may not sound so good to you, and vice versa. "Sounds good" (or bad as the case may be) is a largely subjective judgement and there's seldom any sort of universal agreement. If there were, we wouldn't have anywhere near the diversity of products we have today. Sure, you could probably get some sort of universal agreement between a full size speaker and the little speakers in your PC, but we're usually not dealing with such coarse comparisons.

So to that end, I wouldn't presume to try and explain why something may sound good to someone. That would also beg the question why does it sound bad to someone else? I just accept that we're all human beings and that our subjective experiences and preferences can vary considerably and that no one person's subjective experiences and preferences are inherently any more valid than anyone else's and just leave it at that. Vive la difference!

I prefer to stick to "this is what it is and this is what it does" and leave the subjective issues to be sorted out by each individual for themself.

This probably isn't the sort of answer you were hoping for, but it's the only one I got.

se

[Steve Eddy]

Steve very educational post. I've learned a lot since this thread began about TVCs and other passives. Your knowledge seems vast about this subject. 

Thanks. Now I just have to work on that "e" and an "i" thing.

Your feedback is most welcomed!! I think I as well as others are here to learn. You have been a great help and always welcomed to post here.

Again, thank you. Just don't make me into any sort of guru and unquestioningly accept everything I say as Gospel.

I see you've caught the attention of 6moons in a recent review.

Yeah, and that Bill Whitlock piece was included too so you know Srajan's lurking about the hallways here.

You have a very interesting design using the Transformers(posted earlier in this thread).
I look forward to seeing the finished product! I'm always open to the possiblities of good sound.

Thanks. Though the circuit I posted earlier in this thread isn't going to be the one used in the Ingot. Not enough room in the chassis to accommodate the center tapped chokes. It'll probably be a very simple, single-ended JFET buffer that caught Mike's fancy.

It doesn't matter where or who it's from.

Oh, good. I was worried my prior felony convictions and my craven addiction to heroin might prejudice you against me. 

se