AMC CVT 1030 Preamp

[Markus111]

Does anyone have a schematic and / or manual for the AMC CVT 1030 preamp? It would be much appreciated!

Thanks,
Mark

 

[thomash85715]

Hi Mark: I don't have a schematic but I do have a specimen in the flesh. Do you still have yours? Want to discuss it? We need help with that stupid little IC board in the back corner that was ruining the sound even before it went belly up with DC on its outputs. If you ever did get a schematic, I will pay you something for a copy. Thank you. --Tom

 

[jt1stcav]

http://www.amchome.com/us/index.php

I couldn't find any info on CVT 1030 schematics, but maybe the link above can get you in the right direction...

I owned the CVT 1030s years ago (with sockets), and was my first introduction to tubes within my own system. Controlling a SS McIntosh MC7200 power amp, it sounded pretty damn good with NOS '83 JAN Philips tubes rolled into service (seen here on post 17: http://audiokarma.org/forums/showthread.php?t=56175&page=2).

 

[Markus111]

I still have the cvt 1030, and it's a nice sounding unit. I guess I was fortunate that mine worked, since it also was an eprey purchase. The only mods I've done so far are to install tube sockets on the pc board. I know that they wanted to save costs, but soldering tubes onto a board? The sockets only cost about $10. I would have to believe that anyone would be willing to pay a bit extra for the preamp to have sockets available. You would think it costs them more in overhead to produce and maintain two separate models than to just put the sockets in. The best tubes I've found for this preamp are telefunken smooth plate 12ax7 and JAN / Phillips 12au7. That combo gives this unit a very smooth yet detailed sound.

Mark

 

[jt1stcav]

I agree, having the tubes soldered into place seemed ludicrous to me...I wonder if that model was even profitable at all for Weltronics?

Never experimented with any other tube brands (other than the JAN Philips that replaced the stock Sovtek 9 pins)...the JAN Philips were a major improvement to my inexperienced ears, but I would've liked to have tried Telefunkens or Mullards had I kept the CVT 1030s long enough. Oh well, I'm quite content with my 6SN7 SRPP linestage pre.

 

[theoman]

I'm thinking about buying one, Is there any updates on the issues on this preamp?

 

[Brice]

I had one and I liked it. Very nice unit.

But there are 2 versions if I recall correctly.

The regular and the S version. The S is for socket. It has tube sockets inside so you can tube roll easily.

The other version does not have sockets and the tube is soldered directly into the PCB, which is dumb.

You want the S version, or of you're handy, install yourself tube socket into the PCB.

Other than that, it is a nice preamp.

 

[primosounds]

I still have the cvt 1030, and it's a nice sounding unit. I guess I was fortunate that mine worked, since it also was an eprey purchase. The only mods I've done so far are to install tube sockets on the pc board. I know that they wanted to save costs, but soldering tubes onto a board? The sockets only cost about $10. I would have to believe that anyone would be willing to pay a bit extra for the preamp to have sockets available. You would think it costs them more in overhead to produce and maintain two separate models than to just put the sockets in. The best tubes I've found for this preamp are telefunken smooth plate 12ax7 and JAN / Phillips 12au7. That combo gives this unit a very smooth yet detailed sound.

Mark

Actually soldering the tube directly to the circuit is an idea that the military used to prevent problems. They identified that the tube socket to tube interface was an issue, with bad connections, oxidation, etc. So, if interchangeable or replacement is not an issue, then direct connection to the circuit is a better performing, more reliable design. But, we (audio guys) being inveterate tweakers would think that as lunacy.