My "audiophile" LM3886 approach

Yeah, I know ,the whole integrated amp including a nice case,400VA trafo,integrated non-os DACw supereg power supply ,alps remote volume control,selector, connectors etc cost 450 Euro to make and thats what he paid ,excluding shipping.
A pretty good bargain I guess.I would like to have friends like me;)
 
This is it again
 

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well yes, the switch could have been rotary so another gold plated knob to match.In fact as I had finished the amp I discovered -by chance-that for some strange reason the remote pot sounds worse when powered so I put in a double throw 3 pole main switch so that you can actually listen without the remote circuitry on for critical listening.I remember a similar impression from my Creek passive pre which is based on Alps remote.The difference is quite obvious but I cannot understand it since the motor attached to the pot is not on allthe time.
How´s that for being fussy?
 
Stuey - re. transformer,

I'd suggest a 240V / 400VA 25V+25V Toroidal transformer, only because I have it in my rev c and it performs superbly.
There is no compression at any listenable volume level, into very large 90d, 4 ohm rated speakers (Dips to 4 ohm, but averages higher). transparency,soundstage, detail etc are first rate (system dependant).
I paid $70.75 a year ago for an Antrim transf. from Harbuch Electronics, the manufacturer. tel. 02 94765854. Part number is T2416.
email: HARBUCH@bigpond.com

I have the Full Evolution Amp in the mail, and will be using an Antrim T2216 which is the same 400VA I use in the rev c, but with an Elecrostatic Screen. Mauro says 400VA will be a good compromise. He says I could go as high as a 500VA transformer. In case you are interested, this costs$103.51, incl gst.

Audie.
 
Mauro's Evolution Amp,

Although I am getting the "Full" version Evolution Kit, I will only initially build the "Base" version, as mauro recommends. My rev c is already so good that the only area where I expect a noticeable improvement is in control and definition of the very low bass, which mauro says is one of the areas where the Evolution improves on the rev c.
I am hoping the electrostatic shield on the transformer will make the Evolution amp less prone to the effects of noise on the AC mains than the rev c. The sound quality does vary at different times, though not as much since I started to use my battery powered Leach MC Head Amp that I have been fine tuning for the past month or so (and will be rebuilding).

I may later complete the Evolution to the Full version, if I should start using my little used full - range electrostatics, or my magneplanar MG3s ( need new ribbons). The higher damping factor of the Evolution should benefit my bass reflex floorstanders also.

Audie.
 
Not all that more than the REV C

In Australia the PCB is about 6.4 times, but the Evolution PCB comes with pre-soldered SMDs and 2 heatsinks.
The Base kit (PCB + Base BOM) is nearly 3 times.
Then add money transfer fees.
Worth it though IMHO.

Nordic posted the prices on the bottom of page 254.
Brian has the link to Mauro's Home Page at the top of this page.
Re. the added parts for the Full version, you'll need to send Mauro an email from his web site.

Audie.
 
Stuey,
Harduch build good transformers. I'm thinking of getting a 2000VA 240V/240V Isolation transformer from them as well.
If you go for the 400VA Toroidal transformer, you will need to use a large enough Amplifier slow blow AC mains input fise to withstand the transformer magnetising current inrush at switch-on. Mauro has details of an inrush current circuit on his web site.
I use a 2000VA variac, so I do not have a problem.

An alternativeapproach if you are going to use a case big enough for two transformers, and you only want to buy one transf at the present time, is to use the one 250VA transformer to begin with and then add another 250VA transf later. As Russ points out, that would give the best erformance.

Audie.