GM70 Direct-Coupled Electrostatic Amplifiers

[Ali Tait]

Hi Folks,
Nick is building these monoblocks for me,and we are now at the point of deciding what to make the top plate and front plate out of.I was thinking maybe brushed copper for the top and front plates,with maybe polished copper covers for the transformers to give a little contrast. The chassis will be wood,with metal top and front plates,and the transformers will be mounted in the same style as WAD amps,so the tops will have covers.

Anyone have other ideas what to make them out of? Just thought I'd gather some ideas before making a final decision.

Here's a pic of the proposed layout-

[aquapiranha]

Slate!

Or heat resistant perspex so they look like Orac off Blakes 7...

http://www.blakes-7.co.uk/pictures/gadgets/orac2large.jpg

[Ali Tait]

Ha,that would be different! Actually,Nick just came up with the idea of a full copper chassis a la Anthony's amps.I might go with this if the cost isn't too prohibitive.

[aquapiranha]

I honestly think slate would be nice, but a bugger to machine I would guesss. How about a couple of nice big tiles from B&Q cut to size and fitted in a lovely french oak chassis? hmmm...

Yeah baby!...

http://www.diy.com/diy/jsp/bq/nav.jsp?action=detail&fh_secondid=9277610&fh_view_size=10&fh_start_index=10&fh_location=%2f%2fcatalog01%2fen_GB&fh_search=floor+tiles&fh_eds=%C3%9F&fh_refview=search&ts=1282690292702&isSearch=true

[lurcher]

We could go back to a wood surround, I just remembered I fixed a amp for the chap who makes this sort of furniture.

http://allan-lake.com/furniture/39_18.jpg

I suspect its not cheap though.

http://allan-lake.com/index.php

[Ali Tait]

Looks very nice Nick,though as you say,probably not cheap!

Agreed slate would look nice,but too fragile I think,these are going to be heavy!

[John]

I like the idea of it being completly finished in copper I love the way valves contrast with my copper dac

[pure sound]

I'd go for all copper or maybe copper top plate with wood surround.

There was an ebay seller based in Italy who made rather nice & reasonably priced copper chassis. He's called luci880

I'm not sure if he is still doing them though. Might be worth asking.
If not, I imagine you could probably find someone in the UK who'd fabricate them. Anthony obviously found someone suitable to do the amps he made.

[Ali Tait]

Yes,I've PM'd him.

[Ali Tait]

I'll check out that seller,thanks for that.

[Reid Malenfant]

If you find it's a tad on the expensive side you could always get a steel or possibly aluminium chassis heavily electroplated with copper ;)

I bet Black Chrome would look the business with glowing valves now i have just thought about it :)

[Ali Tait]

Aye I'd thought about the electroplate route too,though I think at the end of the day it would probably be about the same cost by the time I've had the chassis built and found an electroplater.

Black chrome sounds good too!

[Ali Tait]

Hmm,I remember seeing an episode of Orange County Choppers where instead of chrome plating,they nickel plated.I remember that looked very good.Decisions decisions!

[Reid Malenfant]

:lolsign: I have opened a can of worms :doh:

I doubt electroplating will be too expensive, however it's not simply a case of shoving it in a tank. To do a good job it'll need careful preparation & that is where the costs build up ;)

Nearly at 3000 posts Ali :cheers:

[lurcher]

Nickle plate looks nice, its softer than chrome. Remember that copper will need a finish of some sort if its not to tarnish and go nasty in a few days.

[Ali Tait]

Aye Nick.Did Colin have his laquered?

[Ali Tait]

:lolsign: I have opened a can of worms :doh:

I doubt electroplating will be too expensive, however it's not simply a case of shoving it in a tank. To do a good job it'll need careful preparation & that is where the costs build up ;)

Nearly at 3000 posts Ali :cheers:

Haha I need to get out more!

[The Vinyl Adventure]

Have you heard them yet, are they as good as you hoped/expected?

[Ali Tait]

Not built yet Hamish! I've heard the breadboard prototype,using 813 valves,which can't supply as high a voltage as the GM70,and it used some PP output transformers for the chokes,which were too small so bass was compromised.Despite being built with what Nick had to hand,in a lot of ways they were the best amps I've heard,so the proper versions I have every confidence,will be amazing.The chokes have been specifically wound by Sowter for the amp,so bass should be thunderous!

[lurcher]

Not sure I can ever promise thunderous bass from a electrostatic :-)

[Reid Malenfant]

Not sure I can ever promise thunderous bass from a electrostatic :-)
Tell him to buy some Quad 2905s' :eyebrows: They go pretty low & produce very decent bass ;)

[Jonboy]

I think chrome shows up too many scratches from past experience, so nickel might be a safer bet, the more shiney the finish the more it will show up tiny scraches :( how about brushed Aluminium and wood

[lurcher]

Tell him to buy some Quad 2905s' :eyebrows: They go pretty low & produce very decent bass ;)

Low and decent we can do, Thunderous not so much.

[Ali Tait]

Ok,thunderous for a static then! :) The Acorns do go surprisingly low.

[Ali Tait]

I think chrome shows up too many scratches from past experience, so nickel might be a safer bet, the more shiney the finish the more it will show up tiny scraches :( how about brushed Aluminium and wood

Aye,I was considering that also Jon,I may go for a brushed finish on the copper,or whatever I decide to go for.