For Sale: Passive pre-amp.

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28-01-2008, 19:47
Filterlab

For Sale: Passive pre-amp.

My gorgeous transformer based passive pre-amp as featured in the DIY thread.

Wonderful natural and clean sound, nice heavy control, one in one out. Simply not needed anymore.

http://s560.photobucket.com/albums/s...stuff/PP17.jpg

http://s560.photobucket.com/albums/s...stuff/PP16.jpg

http://s560.photobucket.com/albums/s...stuff/PP18.jpg

PM me.
29-01-2008, 13:53
Gromit

Looks gorgeous! :)

I'm being a typical technophobe here (please bear with me!) but how does a transformer-based passive pre work? I notice NVA are now building their pre's with transformer volume controls and wondered how they work.

Sorry for the thread hijack! :o
29-01-2008, 14:12
Filterlab

Quote:

Originally Posted by Gromit

Looks gorgeous! :)

I'm being a typical technophobe here (please bear with me!) but how does a transformer-based passive pre work? I notice NVA are now building their pre's with transformer volume controls and wondered how they work.

Sorry for the thread hijack! :o

Cheers!

Very basically:

At varying points of the transformer windings there are different attenuation values (increasing with the number of windings) and are accessed by the pins on the transformer housing.

http://www.intactaudio.com/images/At...ges/AVC_Lg.jpg

These points are spurred off to the volume switch which is usually a 24 position switch and as each position is selected the attenuation is reduced and the volume increases.

http://www.intactaudio.com/images/At...g-switch-2.jpg

This one certainly works very well indeed and is very natural and transparent. Its only requirement is a low impedance input (say 50 ohms from a source) and a high impedance input on the power amp (say 50 Kohms). The ratio should really be no lower than 100:1 but preferably closer to 1000:1.
29-01-2008, 15:16
Gromit

Thanks for that - looks like a very elegant and clever way of doing things (and even I understood it). :)

Makes sense that it would sound good. :)
31-01-2008, 21:44
Filterlab

http://s560.photobucket.com/albums/s...ff/passive.jpg
31-01-2008, 22:51
Filterlab

Any offer considered - no matter how daft!

Go on, have a go with it. You'll be amazed! :D
06-02-2008, 14:21
Filterlab

Well I paid £350 for it last year, obviously I'm not looking for that much, around a couple of hundred-ish?
06-02-2008, 19:12
pure sound

sounded considerably better than the MFA (silver) to my ears. Didn't ring either! (I borrowed briefly before Rob had it)

Sastus,

The original metal case was RS part No. 364-1632

http://uk.rs-online.com/web/search/s...duct&R=3641632
06-02-2008, 21:38
Filterlab

Cheers matey! Sounds like you know more about it than me. LOL! :D
13-02-2008, 12:22
Filterlab

Going up on eBay this weekend.
28-03-2008, 16:21
Mike

Nice box! :)

Where d'you get it?

:eyebrows:
28-03-2008, 16:48
Filterlab

I made it with my own fair hands. :)
28-03-2008, 17:01
Mike

Hmmm.... nice, looks just about the right size for this 'ere NVA phono board. ;)

What wood is that middle box part made from. I like it. :)
28-03-2008, 17:06
WikiBoy

Quote:

Originally Posted by Filterlab

I made it with my own fair hands. :)

It obviously didn't sell on ebay :eyebrows:

If I were you I would take the transformers out and sell them seperately and throw away the used chopping boards. :mental::lolsign:
28-03-2008, 17:30
Mike

Yeah!... and give me the bit in the middle! :)
29-03-2008, 09:49
Filterlab

Quote:

Originally Posted by Shian7

Hmmm.... nice, looks just about the right size for this 'ere NVA phono board. ;)

What wood is that middle box part made from. I like it. :)

Cherry. :)

Quote:

Originally Posted by Richard

It obviously didn't sell on ebay :eyebrows:

I never listed it, couldn't be bothered and it looks quite nice just sitting on the rack. Will just keep it knocking about until I stash it deep in a cupboard somewhere and then discover it in ten years time or when I next move.
12-05-2008, 10:48
Filterlab

Now sold. :)
23-12-2008, 21:58
Phil Bishop

Passive pre-amp for sale (again)

I bought this off Rob earlier in the year and was mightly impressed. However, Rob introduced me to computer audio and now I no longer need the passive so it is for sale again @ £175 - a bargain.

I have fitted a silver volume control, but will also supply the original brass knob.

e-mail me if interested - bishopfamily@ntlworld.com or phone me on 07747 642586

Thanks
24-12-2008, 08:54
Filterlab

LOL! Nice one Phil, it's a great piece of kit. Maybe you could sell it to i_should_coco, it's his kind of thing. ;)
24-12-2008, 09:58
Phil Bishop

Rob,

Thanks, who is i_should_coco? A member of AOS? I have had some interest already via other contacts, but given the economic situation and Christmas people are a bit short of cash. Funny, I am now exactly in the same position as you were a year or so ago - this is a graet bit of kit, but totally redundant in my present set up. Gone are the days when I would hoard stuff in the loft - it goes straight out for sale now.

I will probably put in on ebay in the new year, but for more than I am asking here.

Best wishes - have a great Christmas

Phil
24-12-2008, 10:59
Filterlab

Hehehehe, I was being a bit cheeky Phil. i_should_coco (Pete) is on here and the Wam - he built that passive, I then bought it from him and recased it. :)

Ebay might be the way to go, but with a BIN and offer rather than an auction (as I did) or you may end us losing a load of cash.

It's a lovely passive though, I'm glad you enjoyed it as much as I did - but like you I didn't have a real use for it and I also sell stuff as soon as it becomes spurious to requirement.
24-12-2008, 11:14
Mike

Quote:

Originally Posted by Filterlab

spurious to requirement.

Come again? :scratch:
24-12-2008, 11:45
Filterlab

Ooops, I meant superfluous. Tut, this beer and Baileys combination does nobody any favours! :lol:
24-12-2008, 20:11
Ali Tait

Try a BMW!
24-12-2008, 20:24
Mike

I've tried three.... they were very difficult to swallow!
25-12-2008, 15:36
anubisgrau

what trannies are inside?
26-12-2008, 20:54
Phil Bishop

I think if you go back to the beginning of this post, Rob describes the transformers - Intact Audio I believe.

Phil
10-10-2009, 17:03
Spectral Morn

Quote:

Originally Posted by Phil Bishop

Hi,

About a year or so ago, someone bought this from me, but has never arranged collection! I have lost their e-mail details. Please get in touch if you still want it! E-mail me at.........

Phil

HI Phil

Its not a good idea to leave your E-Mail address out in the open so I have removed it. However if the person who bought the item of Phil wants to contact Phil PM me and I will give you the Email address .

Regards D S D L
10-10-2009, 17:49
Phil Bishop

Cheers Neil.

Phil
11-10-2009, 22:55
anubisgrau

Here I am:)

Cheers
12-10-2009, 08:42
Spectral Morn

Quote:

Originally Posted by anubisgrau

Here I am:)

Cheers

This is a bit vague. Are you the person Phil was talking about? If so confirm with me via PM and I will give you Phils E-Mail details.

Regards D S D L
12-10-2009, 09:09
anubisgrau

Quote:

Originally Posted by Dalek Supreme D L

This is a bit vague. Are you the person Phil was talking about? If so confirm with me via PM and I will give you Phils E-Mail details.

Regards D S D L

no worries, i've contacted phil already - i do have his details of course

thanks for helping

cheers g.