TVC

[Ali Tait]

I recently purchased a very nice quality passive pre from a member of this parish. Whilst this was a nice sounding bit of kit, I wasn't so keen on the sound of the SMD metal films in the DACT pot, to my ears giving a harsh sound. Nick had kindly sent me a pair of Dave Slagle TVC transformers to try, so I thought I'd fit them to this pre. I wanted to do this in such a way that it could be returned to original with the minimum of fuss.

Here's the pre-

http://i1286.photobucket.com/albums/a616/aliballybee1/IMAG1436_zps6eap9mz5.jpg (http://s1286.photobucket.com/user/aliballybee1/media/IMAG1436_zps6eap9mz5.jpg.html)

Front panel removed, ready to remove pot-

http://i1286.photobucket.com/albums/a616/aliballybee1/IMAG1380_zpsii66mgat.jpg (http://s1286.photobucket.com/user/aliballybee1/media/IMAG1380_zpsii66mgat.jpg.html)

Bought some U section ally to mount the transformers on-

http://i1286.photobucket.com/albums/a616/aliballybee1/IMAG1381_zpsxccce3go.jpg (http://s1286.photobucket.com/user/aliballybee1/media/IMAG1381_zpsxccce3go.jpg.html)

Wiring of volume switch-

http://i1286.photobucket.com/albums/a616/aliballybee1/IMAG1427_zpsspbvlotq.jpg (http://s1286.photobucket.com/user/aliballybee1/media/IMAG1427_zpsspbvlotq.jpg.html)

Pot fitted-

http://i1286.photobucket.com/albums/a616/aliballybee1/IMAG1428_zpsebyuoohm.jpg (http://s1286.photobucket.com/user/aliballybee1/media/IMAG1428_zpsebyuoohm.jpg.html)

Wiring of transformers-

http://i1286.photobucket.com/albums/a616/aliballybee1/IMAG1429_zpspbzriite.jpg (http://s1286.photobucket.com/user/aliballybee1/media/IMAG1429_zpspbzriite.jpg.html)

Finished article-

http://i1286.photobucket.com/albums/a616/aliballybee1/IMAG1432_zpsvsdpp641.jpg (http://s1286.photobucket.com/user/aliballybee1/media/IMAG1432_zpsvsdpp641.jpg.html)

How does it sound? Dunno, just finished late last night, might get it plumbed in this evening if I get a chance.

[struth]

Like tvc's. wouldnt want to change back now

[Ali Tait]

Aye, hoping for good things with this. It'll have to be good to beat the Forte though.

[walpurgis]

Is that a Forte Model 2 you've got Ali?

I was using one until I got my Ming Da MC-9 TVC pre-amp. The Forte was excellent, but the TVC beat it hands down, so I sold it.

I kept my vintage VTL Deluxe valve pre-amp though. It's not quite as lucid as the MC-9, but has the best built in MM phono stage I've heard. Don't use it much though.

[Ali Tait]

Yes a Model 2 Geoff.

[awkwardbydesign]

I've considered putting better switches in my Promitheus TVC, but all those wires! I lose the will to live just looking at them.

[walpurgis]

Yes a Model 2 Geoff.

Very good pre-amp that Ali (wasn't my old one was it? :)). The TVC is likely to make you raise an eyebrow though. Tell us later, when you've given it a spin.

[hifinutt]

looks great , I love TVC`s

[Ali Tait]

Very good pre-amp that Ali (wasn't my old one was it? :)). The TVC is likely to make you raise an eyebrow though. Tell us later, when you've given it a spin.

Yes as a matter of fact. :D

Have plumbed it in. Won't get a proper listen until Friday, but first impressions are a better sense of air and space. Not sure the bass is as good though. Great clarity though, hearing into the music a little more methinks.

Might not have quite the drive of the Forte though.

[walpurgis]

No shortage of bass or drive with mine. I don't reckon I could go back to an active pre-amp now.

[Ali Tait]

I'm not listening at my normal volume though, that'll have to wait till Friday.

[Ali Tait]

Take it back. Turned it up a bit, bass is all there.

[walpurgis]

I found the my MC-9 TVC really brought the Monarchy Audio SM-70 Pro to life. They work together brilliantly!

[Ali Tait]

System has warmed up now, starting to sound very nice!

[RichB]

Interesting thread Ali, been using a passive for a while myself now but I'd like to hear this tvc

[Ali Tait]

Liking this, will bring it to NEBO.

You can buy the trannies here-

http://www.intactaudio.com/atten.html

[Firebottle]

The Firebottle KIN line preamp ousted a Townsend TVC passive in Rob's system, giving more detail. More comparisons maybe?

Sounds like there will be a lot going on at NEBO (how many hours are there in a day?) :)

[Ali Tait]

Aye, be an interesting comparison Alan. Think we need two days!

[Clive]

It's nitpicking but the Slagles are AVCs. They sound great in my system!

[Ali Tait]

LOL aye, but it's still a transformer controlling the volume.

[Clive]

LOL aye, but it's still a transformer controlling the volume.
I said I was nitpicking! It's actually and auto-transformer/autoformer...which does not isolate the way a transformer does.

http://www.intactaudio.com/images/Atten_images/AvsT-.jpg

[Ali Tait]

Yep, only one winding. No isolation between source and amp could be an issue in some systems though.

[awkwardbydesign]

Coincidentally, I have just re-installed my Promitheus TVC (standard version), while I re-box my Stereo Coffee LDR pre, and add a remote control to it. There are differences to the sound, but I couldn't say which is better. The only problem with the TVC is that the attenuator switch clicks when turned. But only when music is playing! It has been suggested that is due to DC being present on the inputs, but I don't know if that's true. Maybe it's just the Chinese 24 way switches, but it would cost over £70 for an Elma switch just to find out! And all those wires! :(

[Ali Tait]

A cap would block the DC. Does it do it from all sources?

[lurcher]

DC on the input to a TVC would cause problem with saturating the core. Its more likely you need a make before break switch.

[awkwardbydesign]

DC on the input to a TVC would cause problem with saturating the core. Its more likely you need a make before break switch.

I'm pretty sure they are make before break. And I'll check if it's every input.

[Ali Tait]

Now had the chance for a proper listen. This is very good indeed. I thought the Forte was good, but this is better in every respect..

[Ali Tait]

Holy shite, the bass out of this is phenomenal!

[Ali Tait]

Had this long enough to get a good handle on it I think, I reckon this is one of the biggest audio bargains out there. This is easily the best pre I've had in my system, a great result given a pair of these autoformers are only 200 dollars. Don't let the low price put you off, performance is stellar. All you need then is a box, selector switch, volume switch, rca's and some wire.

Only caveat - Nick tells me it needs a lowish output impedance from your sources to give of it's best. The inductance can be altered by restacking the lams though, so there is scope for tuning the sound to your system.