Promitheus TVC passive preamp anyone?

0 Members and 3 Guests are viewing this topic. Read 544797 times.

rollo

  • Restricted
  • Posts: 5530
  • Rollo Audio Consulting -
Re: Promitheus TVC passive preamp anyone?
« Reply #1320 on: 18 Mar 2007, 03:30 pm »
Harmon,

      Si Senor, as long as your amp is grounded. If not to the screw holding the cover plate for your duplex outlet.

  rollo

Harmon

Re: Promitheus TVC passive preamp anyone?
« Reply #1321 on: 18 Mar 2007, 03:53 pm »
Thanks rollo. Can I get away with running one wire to both trannies screws, instead of two wires one from each trannie screw, then attach the one wire to a ground? Thanks

rollo

  • Restricted
  • Posts: 5530
  • Rollo Audio Consulting -
Re: Promitheus TVC passive preamp anyone?
« Reply #1322 on: 18 Mar 2007, 04:58 pm »
Thanks rollo. Can I get away with running one wire to both trannies screws, instead of two wires one from each trannie screw, then attach the one wire to a ground? Thanks
 

  Harmon,
               Yes you can, However I would run 2 as it keeps them separated.

   rollo

davetroy

  • Jr. Member
  • Posts: 24
Re: Promitheus TVC passive preamp anyone?
« Reply #1323 on: 18 Mar 2007, 07:41 pm »
In the section of the Promitheus Audio site under "Ebony Cones," the TVC seems to be sitting on top of some kind of wood platform. Nicholas, if you read this, what is that?

Whitese

Re: Promitheus TVC passive preamp anyone?
« Reply #1324 on: 18 Mar 2007, 07:50 pm »
Whitese,

            Looking good man. Vintage you say eh! Is that EL 84 based?

    Happy Listening

   rollo

Its a 6MB8 output tube unit....pretty nice,...although if i sell my extra TT I am getting a McIntosh MA230 or MAC1500....just for a bit more power and finesse...

anubisgrau

  • Full Member
  • Posts: 386
Re: Promitheus TVC passive preamp anyone?
« Reply #1325 on: 18 Mar 2007, 08:37 pm »

           Now to me imaging and staging create the illusion of the real thing. Now the TVC presents a bigger more 3D image than it ever did. There is more space between the instruments and the depth is more evident in the recording when present.
           Out of the box this TVC  outperforms its predecessor by a long shot. It sounds as if it has been broken in for a while. When I put the first unit in [single box silver wired dual mono] the top and overall sound was thin and over detailed. over time it basically went away. To date the original unit has changed and still sounds great. In comparison the new unit just has the weight and authority of the real deal. Female voice will give you goosebumps.
           I believe that the TVC in this configuration is now better than the S&B we compared the first unit too. My active pre is crying now as it well should as it may have finally lost its home. Well for CD anyway, the phono section can be used independently by bypassing the linestage.
       

Rollo, glad that in a way you confirmed my impressions that the earlier versions of Promitheus had a substantial space for sonic improvement. Very good but not good enough for a really demanding system. Being spoiled with a very good home-made TVC, your version of Promitheus is something I'd love to test against it.

Hopefully Nick will offer this version to those who demand only the best.

G.

rollo

  • Restricted
  • Posts: 5530
  • Rollo Audio Consulting -
Re: Promitheus TVC passive preamp anyone?
« Reply #1326 on: 18 Mar 2007, 10:30 pm »
anubisgrau,

        Earliar in my original review of the dual mono silver wiring I had the same impression as your listening panel. Compared to the Loesch & Weisner active preamp I felt the body and weight of the TVC was that of omission rather than fault. The TVC is not lean or lacks weight, however compared to the active it does. Now we are taking a $7500 active against a $530 TVC. I MO the silver wiring contributed to that character.
        The new dual mono with copper wiring has taken the TVC so close in character to the active that it is now a toss up. Since there is only 50 HRs or so on the new unit it is too early for a shootout. In another 300 Hrs we all will know.
         The fact that it is even in the same league is just unbelievable. If it equals or surpasses what I hear with the active I think I'll crap myself. To be honest I believe it WILL.
          If it was not for the superb phono section of the Loesch, it would be out of here. Next week I will be receiving the active buffer from Promitheus. This combo should put the argument to its final resting place.
          So for vinyl it will be Linn LP12, L & W phono stage, Promitheus TVC, then
Pre/Buffer. The gain of the Pre/Buffer can be adjusted to suit your specific needs.
           rollo
P.S. The TVC is available to all, it just costs more money.

guest1632

  • Guest
Re: Promitheus TVC passive preamp anyone?
« Reply #1327 on: 18 Mar 2007, 11:10 pm »
Ray,
        The TVC has one input and two outputs. He left the buss for the negative. However that is going to be eliminated.
 
        Ray the return run from the buss is connected to the first terminal just right of the nut that holds the attenuator together [top right]. The buss is connected to both input and output negative legs. I feel the returns should be separated from each other. So you will require a wire for each return. I believe the individual wires all get connected to this terminal described above, however I am not sure if there are additional taps for each return or they are gang soldered to the one terminal.
        I requested additional wire and a clarification from Nicholas. I am awaiting a response. Will let you know as soon as I know. I am pretty sure its the one terminal but I want to make sure.

  rollo
P.S.  Harmon I am a big jazz fan myself. Ray Brown is in the House right now with Gene Harris. Red Hot Trio.

Hi Rollo,

 I have always felt the grounds should be a separate item. So if both go to that same terminal, then you essentially have the bus connections, just in a different way. On mine both the positive ins and outputs buses are separate. The ground bus on both are together. I don't have any silver wire, otherwise I might just clip/separate the 2 and ground them both useing the screws of each transformer. Plus, gotta get some good silver solder too.

Ray

anubisgrau

  • Full Member
  • Posts: 386
Re: Promitheus TVC passive preamp anyone?
« Reply #1328 on: 18 Mar 2007, 11:20 pm »

Next week I will be receiving the active buffer from Promitheus. This combo should put the argument to its final resting place.

I don't want to sound as someone who is always complaining, but I think that the idea of active buffer is opposite to the concept of TVC.

For me, TVC is a long copper wire with attenuation, meaning the audio truth with adjustable volume.

I can accept that TVC plus active buffer combo may sound more pleasant but I can't imagine it can sound more truthful.

But than I know tons of audiophiles who prefer pleasure to truth in audio. Not me.

guest1632

  • Guest
Re: Promitheus TVC passive preamp anyone?
« Reply #1329 on: 18 Mar 2007, 11:47 pm »

Next week I will be receiving the active buffer from Promitheus. This combo should put the argument to its final resting place.

I don't want to sound as someone who is always complaining, but I think that the idea of active buffer is opposite to the concept of TVC.

For me, TVC is a long copper wire with attenuation, meaning the audio truth with adjustable volume.

I can accept that TVC plus active buffer combo may sound more pleasant but I can't imagine it can sound more truthful.

But than I know tons of audiophiles who prefer pleasure to truth in audio. Not me.

Hi anubisgrau,

Well, I think I can disagree and agree with you at the same time. Firstly as far as the wire with attenuation goes, total agreement. Now here's the rub. Anyone who has done any amplifier design, (not including me), has to deal with how to attenuate a signal without any change in freq response. In the past, it's always been done with a form of resistance. So, now here's where a TVC comes in to play. If you wire the TVC in to the amp's circuit, you no longer have that resistive issue. Now the amp or preamp can do what it is suppose to do and do it without any comporomises. Now the downside of all this is the expense and time to wire up the TVC. Whereas before you just install a potenimeter with just two or three legsWhat you have to do is to think of the preamp with the TVC incorporated, not as two separate pieces. Obviously, the preamp builder would have to do some exact designing to include the TVC at its best. The final process would be worth it.

Regards,
Ray

rollo

  • Restricted
  • Posts: 5530
  • Rollo Audio Consulting -
Re: Promitheus TVC passive preamp anyone?
« Reply #1330 on: 19 Mar 2007, 01:25 am »
Ray,
        The TVC has one input and two outputs. He left the buss for the negative. However that is going to be eliminated.
 
        Ray the return run from the buss is connected to the first terminal just right of the nut that holds the attenuator together [top right]. The buss is connected to both input and output negative legs. I feel the returns should be separated from each other. So you will require a wire for each return. I believe the individual wires all get connected to this terminal described above, however I am not sure if there are additional taps for each return or they are gang soldered to the one terminal.
        I requested additional wire and a clarification from Nicholas. I am awaiting a response. Will let you know as soon as I know. I am pretty sure its the one terminal but I want to make sure.

  rollo
P.S.  Harmon I am a big jazz fan myself. Ray Brown is in the House right now with Gene Harris. Red Hot Trio.

Hi Rollo,

 I have always felt the grounds should be a separate item. So if both go to that same terminal, then you essentially have the bus connections, just in a different way. On mine both the positive ins and outputs buses are separate. The ground bus on both are together. I don't have any silver wire, otherwise I might just clip/separate the 2 and ground them both using the screws of each transformer. Plus, gotta get some good silver solder too.

Ray
 

 Ray

 I believe you misunderstood me . The buss as there is only one is connected to both input and output negative legs of RCA. The buss is fine for the outputs. However the single input negative leg should NOT be connected to the buss. Further it is a silver wire for the buss as well as the hook up to buss. My preference is not to have any buss whatsoever.
     What puzzles me is that at the attenuator Nicholas connected the return leg of both input and outputs to ONE terminal.

 rollo

rollo

  • Restricted
  • Posts: 5530
  • Rollo Audio Consulting -
Re: Promitheus TVC passive preamp anyone?
« Reply #1331 on: 19 Mar 2007, 01:40 am »

Next week I will be receiving the active buffer from Promitheus. This combo should put the argument to its final resting place.

I don't want to sound as someone who is always complaining, but I think that the idea of active buffer is opposite to the concept of TVC.

For me, TVC is a long copper wire with attenuation, meaning the audio truth with adjustable volume.

I can accept that TVC plus active buffer combo may sound more pleasant but I can't imagine it can sound more truthful.

But than I know tons of audiophiles who prefer pleasure to truth in audio. Not me.
 

anubisgrau,
                  Just think of the TVC on Steroids. It is not a matter of truth Vs. pleasure it is both. The TVC lacks the ultimate in body and soul. With the addition of the Pre/Buffer the body and soul will be restored but with the clarity of the TVC.
            IMO it is unfair to make such bold statements without hearing the combo. We have tested the TVC with several active preamps that were not designed to mate with the TVC with wonderfull to OK results. With an active designed specifically for this use it  works real well. To Quote Nicholas " The only way I will listen to the TVC without the active is when I need to save electricity".
           So if  you are patient I will have one soon and report my findings and the matter will be put to rest one way or the other.
         
   Cheers rollo

NewBuyer

  • Full Member
  • Posts: 612
Promitheus TVC passive preamp anyone?
« Reply #1332 on: 19 Mar 2007, 02:01 am »
Just wanted to mention that the solid-state Burson Buffer works fantastically with the TVC, perhaps preferable to a tube buffer. Worth a try for anybody interested in adding a buffer to their TVC combos.

By the way rollo, just wondering here: Are you proposing that it would be sonically better if the input RCA ground connections and output RCA ground connections in the TVC (which Nicholas ties together internally) were not connected together? :?:


guest1632

  • Guest
Re: Promitheus TVC passive preamp anyone?
« Reply #1333 on: 19 Mar 2007, 07:20 am »
Ray,
        The TVC has one input and two outputs. He left the buss for the negative. However that is going to be eliminated.
 
        Ray the return run from the buss is connected to the first terminal just right of the nut that holds the attenuator together [top right]. The buss is connected to both input and output negative legs. I feel the returns should be separated from each other. So you will require a wire for each return. I believe the individual wires all get connected to this terminal described above, however I am not sure if there are additional taps for each return or they are gang soldered to the one terminal.
        I requested additional wire and a clarification from Nicholas. I am awaiting a response. Will let you know as soon as I know. I am pretty sure its the one terminal but I want to make sure.

  rollo
P.S.  Harmon I am a big jazz fan myself. Ray Brown is in the House right now with Gene Harris. Red Hot Trio.

Hi Rollo,

 I have always felt the grounds should be a separate item. So if both go to that same terminal, then you essentially have the bus connections, just in a different way. On mine both the positive ins and outputs buses are separate. The ground bus on both are together. I don't have any silver wire, otherwise I might just clip/separate the 2 and ground them both using the screws of each transformer. Plus, gotta get some good silver solder too.

Ray
 

 Ray

 I believe you misunderstood me . The buss as there is only one is connected to both input and output negative legs of RCA. The buss is fine for the outputs. However the single input negative leg should NOT be connected to the buss. Further it is a silver wire for the buss as well as the hook up to buss. My preference is not to have any buss whatsoever.
     What puzzles me is that at the attenuator Nicholas connected the return leg of both input and outputs to ONE terminal.

 rollo

Hi Rollo,

heheh, We're both saying the same thing. I too would prefer no bus at all. So for grins, if I clipped and thus separated both ins and outs ground buses, I've have to reground them somewhere. With the buses, he uses less wires. On the positive/hot/return side, the ins and outs are already separated.
So if I were to then ground the neg. side to each transformer? what do you think? Would that be a waste of time?

Ray

jonners

Re: Promitheus TVC passive preamp anyone?
« Reply #1334 on: 19 Mar 2007, 09:38 am »

By the way rollo, just wondering here: Are you proposing that it would be sonically better if the input RCA ground connections and output RCA ground connections in the TVC (which Nicholas ties together internally) were not connected together? :?:



As I said in an previous post, I don't think you can separate input and output grounds because I believe the current TVC's are connected as autoformers, not transformers.

guest1632

  • Guest
Re: Promitheus TVC passive preamp anyone?
« Reply #1335 on: 19 Mar 2007, 09:52 am »

By the way rollo, just wondering here: Are you proposing that it would be sonically better if the input RCA ground connections and output RCA ground connections in the TVC (which Nicholas ties together internally) were not connected together? :?:



As I said in an previous post, I don't think you can separate input and output grounds because I believe the current TVC's are connected as autoformers, not transformers.

Hello, Now if I understand about these TVC's Nicholas is using transformers.

Ray

rollo

  • Restricted
  • Posts: 5530
  • Rollo Audio Consulting -
Re: Promitheus TVC passive preamp anyone?
« Reply #1336 on: 19 Mar 2007, 04:26 pm »
Ray,
       I am confused about this. I am not sure if the grounding scheme was done this way to save wire or it had to be done this way. It just just does not make sense to me to tie the the input and output connections together at the attenuator. There must be another tap available on the attenuator for this IMO.
        Nicholas are you listening? Am I nuts or on the right track.

rollo

   
« Last Edit: 19 Mar 2007, 04:37 pm by rollo »

guest1632

  • Guest
Re: Promitheus TVC passive preamp anyone?
« Reply #1337 on: 19 Mar 2007, 04:37 pm »
Ray,
       I am confused about this. I am not sure if the grounding scheme was done this way to save wire or it had to be done this way.
        Nicholas are you listening? Am I nuts or on the right track

rollo

   
 

Hi Rollo,

No problem. will wait to chek out what is correct for the wiring. No rush either.

Ray

rollo

  • Restricted
  • Posts: 5530
  • Rollo Audio Consulting -
Re: Promitheus TVC passive preamp anyone?
« Reply #1338 on: 19 Mar 2007, 04:43 pm »

By the way rollo, just wondering here: Are you proposing that it would be sonically better if the input RCA ground connections and output RCA ground connections in the TVC (which Nicholas ties together internally) were not connected together? :?:



As I said in an previous post, I don't think you can separate input and output grounds because I believe the current TVC's are connected as autoformers, not transformers.
 

    Yes IMO, I feel the addition of individual returns would be a benefit. As far as the autoformer is concerned you make a valid point which I can not answer. I believe they are transformers not autoformers. Nicholas must address this matter as I am puzzled with the hook up as is.

   rollo

rollo

  • Restricted
  • Posts: 5530
  • Rollo Audio Consulting -
Re: Promitheus TVC passive preamp anyone?
« Reply #1339 on: 19 Mar 2007, 04:48 pm »
Ray,

       We will get a clarification from Nicholas. Your right no hurry. As is the new unit is performing above my expectations. However I would like to hear if there is any benefit to the revised scheme which eliminates the buss altogether. It may be overkill but it is worth a try.

  rollo