TVC Sound

Can someone explain to me the mechanism by which croc clips affect sound quality as the volume is lowered?

Rob,

In 1981, the importance of ultrasonics was even less understood than it is today. That's why I asked - the article looked very dated.

 

Folks,

Unbelievable how many posts you generate on a Sunday afternoon, with an englad game on AND F1.... I was having a seriously relaxed Sunday and a few beer.

There are several points I want to comment on, but it will have to wait untill the evening....

Ciao T

 

The croc clips were swapped from wire to wire to change the attenuation. Sometimes the croc made better conenction than others. I noted this and reseated the croc on one occasion where sound quality was lowered. This fixed the problem. That it occurred when the clips were swapped to higher attenuation was purely conicidental. It no longer occurs with the cores fitted in the django.

 

http://www.audioasylum.com/audio/vinyl/messages/546581.html

review of silver v copper stepup. copper seems to come out on top

 

These sort of comments are absolutely meaningless without putting them into context!!!?? What was the system, and what was the 2.2K active preamp? Its like 'My friend's JMLab Micro Utopia Be's were comprehensively beaten in ALL areas and at ALL volume levels by my 1K active speakers', n'est-ce pas?

 

I am betting its a unit WM stocks

Comeon tony... give us a context.

 

this is all getting ridiculous.

some people like it and buy it, some people don't like it and don't buy it.

it's worthy of an audition at home.

 

Ian, The Glasshouse sounds a lot better now. I've replaced the attenuator with the DACT CT2 I bought from Lee. It goes louder as well courtesy of unity gain as opposed to -6db max. I still plan to build the TVC as soon as the bloody parts arrive.

 

sorry for reviving the old thread, but i've just got a message from a guy from my area who got (as a gift) a sort of very interesting device.

it is a TVC based on old and cult UTC transformers, known from the 50s and 60s valve amps. a basic schematic is the following:

In--> 2 pole Selector --> UTC LS30x ---> 24 pole ladder attenuator --> UTC LS12 --> out

any ideas for DIY-ers what is to be expected from it and what would be a value (lets say of the parts)?

 

here are some pics

 

I like the sound of my TVC pre, sometimes a little bright in my system though.


I listen between 20db and 0 db in my system.

 

Blimey- that'a loud!

 

Actually it's not, and I don't know why.

At a little past halfway (I'll check tonight what level of attenuation) I was measuring about 80dba at 1 meter with music playing.

That is a little quieter than I listen to it.

In fact I'll measure it properly tonight.

 

I thought you meant between 20 and 0 on the Music first dial. 0 is full volume.

 

I think my dial is the same.

0db is max volume and some records do get played at 0db.

 

You must just have a power amp with fairly low input sensitivity. IME the TVC would work better like that as it does less 'transforming' although doubtless others will disagree!

 

I must, yet I can't find any published specs for it.

It's odd becasue it's 100 watss into 8 ohm according to the manufacturer with medium sensitivity speakers.

the output of my phono stage is less than 2 volts though.