[anubisgrau]

what is a waiting time for a ref TVC at the moment?
thanks

[guest1632]

...Would like to gain some feedback on our up coming dacs

I will be basing the DAC on Non-Os using the 1545 chip. By i will be using a nickel core special wound by us pulse transformer and the output of dac goes into an active stage. The active stage will have a transformer output.
On the active stage what do guys think, do a tube stage or a solid state stage? Do i focus on one or just do both versions?
As you know by now i am a big fan of trans and impedance matching hence the dac we will be making will feature this same effect...

Hi Nick, Well, why does it have to be active. KISS Keep It Simple Son. That should be a killer. then you can make a box with the TVC and DAC in one box. Also, don't understand the different top plates Stainless steel versus brass, brass isn't that magnetic. I'd think you would use an aluminum topplate because it's not magnetic.


Regards,
Ray

Please do both versions. I am personally most interested in the solid state version, but I think you will find many customers for each version.

Questions/requests regarding the DAC:
- If using the 1545 chip, can you still do filterless and passive I/V?
- If USB input is included, can the USB signal also be transformer-isolated?
- In the active stage, can you do a discrete op-amp approach (similar to the Burson Discrete Op-Amp?
- Can you choose a digital receiver that accepts a 96kHz signal, e.g. like the CS8414?

I am very interested in this DAC, I can hardly wait for it to arrive. The separate power supply idea is very nice.

I also wonder if GHM has received his Power Energizer yet...

[akmal00]

what is a waiting time for a ref TVC at the moment?
thanks

I just got mine yesterday. This is the dual mono version. I waited for nearly 8 weeks. However the wait was worth it as it immediately changed my system. I am using it with my Holfi Audis integrated. I don't have any amplifier yet. Did not want to wait for the price to go up. For the rest of the AC community, the wait if painful but you will forget once it is hooked onto your system. Event when running through an integrated amp like mine. It definitely improves when left burning in.

I bought the ebony knobs thinking that it was just for the looks. Asked Nicholas to send me the normal knobs as well. However when I changed the knobs I had a pleasant surprise. There was audio improvement. The soundstage opens up, the vocals were clearer, the mids and highs were better. The whole presentation was just better. I had to checked that I was not imagining things. But the improvements were there. And it cost only 60 USD.

When played using my TT and CDP both had marked inprovements.

My system is as such:
1) Clearaudio Emotion/ Satisfy/ Benz MC 20E II/ Custom made Phono amp/ Power supply speed controller
2) Maranz CD 63 KI Sig.
3) Holfi Audis
4) QLN cubic III.
5) Audioquest type 4/ Clearaudio Clearwater/ Supra IC

The vocals were sweeter, much clearer. I heard things like the tapping of a tamborine on the singer hand. I had this system for 9 years (apart from the TT). The LP's that had noise were also quieter. And the musicality of my system was definitely awsome. The ref TVC in being run in overnight now. I only turn up the volume by one and I can hear the music from the next room (at night). Normally I have to turn to 7 o'clock to hear any sound. I can listen happily at this level now (single click of the knob only).

I had a listen at the power energizer again. This time i made a better comparison with/ without. The inprovement is more than significant. The vocals improved. The mids were better. The separation also improved. The sound was more focused and sweet.

Nicholas also send me a pair of silver IC to try out. I'm keeping them now. Nicholas I owe you 65 USD. Without it my system had another layer veiling the music. Switched the IC's and that veil disappeared. The sound of my system used to be restrained. It was as if the vocals and instruments were held back and it had to be push through the speakers. Now the sound is effortless. The voices of Louise Amstrong and Ella was just flowing through my room at low volume levels.

I always though that the shorter the route between the source and speakers was better. I can't explain why but placing the TVC and an extra IC improves it a whole lot.

Anyone can explained how the TVC improves the system in with and integrated down the line.

[GHM]

akmal00,
I know of one audiophile that uses two preamps before his amplifier. The first is a tubed active preamp then a TVC. As crazy as it sounds.. He told me he liked the sound better with the TVC between his active tubed preamp and the amplifier and couldn't figure out why it sounded better. I for one do not have an answer. I use the Promitheus with an integrated, but I have a direct input and bypass switch to take the pot out of the circuit.

Once you get an amplifier that has a direct input. You'll most likely hear more than you're hearing now.

I'm not too keen on the knobs making a difference in sound though. I would love to have them..but it would be more about the looks than sound.

I'm glad to read you're enjoying the unit. You are right the waiting is very painful..but also very rewarding once the unit is in the system.

[guest1632]

what is a waiting time for a ref TVC at the moment?
thanks

I just got mine yesterday. This is the dual mono version. I waited for nearly 8 weeks. However the wait was worth it as it immediately changed my system. I am using it with my Holfi Audis integrated. I don't have any amplifier yet. Did not want to wait for the price to go up. For the rest of the AC community, the wait if painful but you will forget once it is hooked onto your system. Event when running through an integrated amp like mine. It definitely improves when left burning in.

I bought the ebony knobs thinking that it was just for the looks. Asked Nicholas to send me the normal knobs as well. However when I changed the knobs I had a pleasant surprise. There was audio improvement. The soundstage opens up, the vocals were clearer, the mids and highs were better. The whole presentation was just better. I had to checked that I was not imagining things. But the improvements were there. And it cost only 60 USD.

When played using my TT and CDP both had marked inprovements.

My system is as such:
1) Clearaudio Emotion/ Satisfy/ Benz MC 20E II/ Custom made Phono amp/ Power supply speed controller
2) Maranz CD 63 KI Sig.
3) Holfi Audis
4) QLN cubic III.
5) Audioquest type 4/ Clearaudio Clearwater/ Supra IC

The vocals were sweeter, much clearer. I heard things like the tapping of a tamborine on the singer hand. I had this system for 9 years (apart from the TT). The LP's that had noise were also quieter. And the musicality of my system was definitely awsome. The ref TVC in being run in overnight now. I only turn up the volume by one and I can hear the music from the next room (at night). Normally I have to turn to 7 o'clock to hear any sound. I can listen happily at this level now (single click of the knob only).

I had a listen at the power energizer again. This time i made a better comparison with/ without. The inprovement is more than significant. The vocals improved. The mids were better. The separation also improved. The sound was more focused and sweet.

Nicholas also send me a pair of silver IC to try out. I'm keeping them now. Nicholas I owe you 65 USD. Without it my system had another layer veiling the music. Switched the IC's and that veil disappeared. The sound of my system used to be restrained. It was as if the vocals and instruments were held back and it had to be push through the speakers. Now the sound is effortless. The voices of Louise Amstrong and Ella was just flowing through my room at low volume levels.

I always though that the shorter the route between the source and speakers was better. I can't explain why but placing the TVC and an extra IC improves it a whole lot.

Anyone can explained how the TVC improves the system in with and integrated down the line.

Hi, Interesting on the ebony knobs. Are the shafts that the knobs fit in, are they metal? I suspect we or Nicholas has some dampening somewhere maybe on the switch. I wouldn't think changing knobs would make that much difference.

How thick is the front plate where the knobs are mounted. Are the switches  directly mounted on the front panel, or is there just a hole drilled in the panel. Well as soon as I have some mula in hand, got to get one of these to see what can be done on a cost affective scale to completely deaden the box.

Ray

[NewBuyer]

...I just got mine yesterday. This is the dual mono version... I bought the ebony knobs thinking that it was just for the looks.

Thanks akmal00 for the review and information!

Can you please post a pic of your reference version TVC with the ebony knobs? I would really like to see what the unit looks like with the knobs, and if the different types of wood match well together cosmetically.

By the way, did you hear similar sonic improvements with digital sources as well as LP's?

Also, if everything is so loud on a single volume click, do you consider this a problem?

[akmal00]

...I just got mine yesterday. This is the dual mono version... I bought the ebony knobs thinking that it was just for the looks.

Thanks akmal00 for the review and information!

Can you please post a pic of your reference version TVC with the ebony knobs? Also, if everything is so loud on a single volume click, do you consider this a problem?

I don't consider the volume level as a problem. However the graduation after that is a gradual slope or curve if you're considering a graft. I put it up to 9 o'clock. However it is louder than my integrated alone.
My description of the sonic improvements with the knobs may sound a bit exaggerated but it is there. Try it. The cosmetic improvements is enough for me already. To each his own poison.

Here are a few pics that I just took. The other thing is that one of my speakers is located next to the cupboard. Increasing the right channel volume helps in my case.

Here's a thought, the tvc connected to a pair of monoblocks. One each for the tweeter and drive units.
Waiting for the hybrid amps from Nicholas. Sounds like next year only that we are gonna see the amps.







The knobs are connected to metal rods that comes out from a drilled hole in the wooden casing. Did not open the cover though. The improvements are both with LP's and CD. My system is not the most revealing anyway. I wonder what's the effect in a more revealing or neutral system.

Bye.

[GHM]

akmal00,

I've been reading up on your integrated. Looks really nice!! The info page states that your integrated uses a fixed resistor before the volume meter(Alps I think). Here's a quote for the page.

"To reduce the influence on sound quality from the volume meter, a high quality fixed resistor is put in front of the volume meter, with the volume meter coupling only a part of the signal to ground. By doing this, the best possible sound quality is achieved. Please note, as a result of this coupling, the signal is only down minus 80 dB, when turning the volume knob to its minimum".

I can only assume the TVC with its higher current and lower output impedance is making the most differences in what you hear right now. I'm no EE so this is just a guess.
Looking at the Holfi components..they match well with the Promitheus!

Hey if it works for you..that's all that matters. You're not the only one using dual volume controls. I suspect there are others using the Promitheus with units like Vinnies Sig 30s or 70's which have stepped attenuators in the path.

[wendell]

Ok,  I was the one that purchased the TVC on Audiogon a week ago.   I received it today and It is a fine pre,  I need to do more listening.


What I do not like about the pre is that when I increase the volume it isn't gradual or balanced.  I have to put this thing at 2 o'clock to let it sing.  anything less and It sounds veiled in the highs and lows.  And when it gets a the 2 o'clock position it seems it gets a boost of some sort. Anyone else have the same problem.

Also, the quality of the build is so so but for what you pay it's a bargain.

Wendell

[wendell]

ok, so I opened the TVC and found 3 broken strands which may be the problem,  it looks as if a few strands were pinched somehow and broke a few.


I have e-mailed the original owner to see if he knows about them or how they may have happen.  he sold due to system incompatability which this may have been the culprit,  I've also e-mailed Nick and Promethius to see if this is common in the building process.

How would you folks handle a situation like this?

[TomekZ]

Alas, I've the same concern at the 2 o'clock setting. With efficient speakers, I don't have to go past 2 o'clock, but it bothers me.

[NewBuyer]

...when I increase the volume it isn't gradual or balanced... when it gets a the 2 o'clock position it seems it gets a boost of some sort... I opened the TVC and found 3 broken strands which may be the problem,  it looks as if a few strands were pinched somehow and broke a few. ...How would you folks handle a situation like this?

Those copper strands in the ver.3 TVC's are very, very thin indeed. I think this is a good question, I hope somebody here has a suggestion. Assuming both ends of a particular broken strand were identified, what would be the best way to "rejoin" them? Would it require a particular type of solder, or something easier/simpler? Would the rejoining method in any way compromise sonics, compared to the original unbroken copper strand?

[gooberdude]

This is my 1st TVC and have come across a bit of an anomoly.  If i have 2 sources plugged in and both are playing, the music from the selected source is quite harsh.  Once the source that i'm not listening to is turned off, this harshness goes away.

I've been burning-in the TVC using a cable TV box.  A few occasions i've come home and fired up the CD player w/o turning off the cable box.  the sound takes on a HF shrill and the mids 'unsweeten'.   Once the cable box is off though, the problem disappears 100%.


Hang in there Wendell, once the TVC is fixed you'll be set.

[samplesj]

This is my 1st TVC and have come across a bit of an anomoly.  If i have 2 sources plugged in and both are playing, the music from the selected source is quite harsh.  Once the source that i'm not listening to is turned off, this harshness goes away.

That doesn't sound like it has anything to do with it being a TVC.  The input jacks ought to be totally isolated by the switch and the TVC should only see 1 input signal at a time. 

I suppose where these transformers are unshielded you might be getting some type of RF interference, but it should be designed to avoid that.

[gooberdude]

No clue why this happens, but my guess is anyone with this TVC that has more than one input can test it out.    The problem goes away 100% when the 2nd source is stopped or turned off...


i'd never have 2 sources going at the same time, its just an issue that arose when i was burning-in the tvc.

[GHM]

I've ran an Arcam DVD player and the Paradisea Dac at the same time... No problems at all. I did this while doing comparisons and switching between sources. Not sure whats going on with your setup Matt?

[gooberdude]

No idea either Gymane, but its not an issue really - just a strange observation.

since i'm new to home audio, i hear the term 'tipped up' thrown about but couldn't get what that meant.  if it has something to do with weird HF standout, then, in my system, when 2 sources are playing simultaneously the sound is 'tipped up'.   its not too hard to press the stop button though to make it go away 100%!      i've not observed this with any other pre i've owned.


What are your thoughts regarding the Energizer?   is it worth the $?

[GHM]

No idea either Gymane, but its not an issue really - just a strange observation.

since i'm new to home audio, i hear the term 'tipped up' thrown about but couldn't get what that meant.  if it has something to do with weird HF standout, then, in my system, when 2 sources are playing simultaneously the sound is 'tipped up'.   its not too hard to press the stop button though to make it go away 100%!      i've not observed this with any other pre i've owned.


What are your thoughts regarding the Energizer?   is it worth the $?

Hi Matt,

I'm still waiting for the Energizer and Reference TVC to arrive. My other TVC is with Maxwalrath right now. So I'm waiting feverishly for this stuff to show up. I haven't listened to my system since I sent the TVC off..just doesn't sound good without the TVC now. The volume pot doesn't cut it for me anymore. I guess I've been spoiled a bit. Bummer about the loose wires and such. Hope the V3 unit arrives in good shape like the V2 did.

[NewBuyer]

This is my 1st TVC and have come across a bit of an anomoly.  If i have 2 sources plugged in and both are playing, the music from the selected source is quite harsh.  Once the source that i'm not listening to is turned off, this harshness goes away.

I've been burning-in the TVC using a cable TV box.  A few occasions i've come home and fired up the CD player w/o turning off the cable box.  the sound takes on a HF shrill and the mids 'unsweeten'.   Once the cable box is off though, the problem disappears 100%...

All of the input/output grounds of the TVC are tied together internally. So while interference from the cable box might not be entering the transformers directly, it could still be riding along the TVC signal ground and thus indirectly producing a voltage drop and/or other audible aspect to the selected signal source. My guess here is that since one of your sources is a cable box, the issue may be a difference in ground potential between cable and audio sources (i.e. ground loop style problem). Ground signal traveling along the path from cable box ground to second source ground, etc.

I really wish there was a way to make a TVC to have the input/output grounds not tied together, as then the TVC could act like an isolation transformer as well as attenuator, and this could theoretically have excellent audio results. However my understanding is that if the input and output grounds were not tied together, then radio and other interferences would simply have to enter the transformers instead, causing an even worse situation.

Perhaps others here can add to these speculations...

Edit: Gooberdude, trying a cable TV RF isolator (like the Jensen VRD-1FF) on the coax cable feeding the cable box might be worth trying in this situation also, if you wish to keep using the cable box as input to your TVC...

[PromitheusAudio]

HI guys
i am currently helping out wendell to sort out his problems. In due time should be able to sort out his problems.

Actually on gooberdudes finding, i would like to ellaborate more on my findings too.

Normally when i work, i work with my pc based audio system on. Also i have this bad habit when i switch cables i do not turn off the amplifier. My source is my comp. So what happens is when i disconnect the interconnects from the tvc and let the interconnects hang loose near the amplifer(my tvc is stack on top off my amplifer). I actually can hear sound coming out of my speakers. faint and distorted. But it is audible. I did not plug any cables in just the interconnects are sitting on top  or near by the metal cassing of the amplifer. Some how the sounds gets transmited thru the rca cables into the amp.

So same thing if you have 2 sources playing thru the tvc. Even thru the selector switch which isolates stuff, you will get some form of interference whether you like it or not. Hence this forms the same basis on which the dual mono version is better as the wires are totaly isolated and do not interfere with each other.

Also one way of preventing the transformers from coming loose from shipment is to use the nylon locking nuts. I will be changing to this to prevent any more faults due to shipment. I not how they can come loose considering i am using aready spring washer.

Gymane, i will be shipping out your stuff on next monday. Will be a big package though.