Mini-2

[MikeW]

I will have a couple extra boards next week. They are the same size as the mini-A.

 

[MikeW]

schematic

 

[Mark A. Gulbrandsen]

Mike,

I sent you an e-mail regarding the boards. Would like 4 if there are that many extra avail.

Mark

 

[MikeW]

board

top

 

[MikeW]

BOARD SIZE

Same as these. Mini-a

 

[MikeW]

2nd

 

[MikeW]

3RD

 

[MikeW]

4TH

 

[moe29]

very sweet!

those heatsinks get pretty crispy?

do you know how many watts you are dissipating?

very cool looks like a real amp


-----------------------------------------------------------
"one day i'm going to grow wings..."
-----------------------------------------------------------

 

[MikeW]

102 (17 volts*3 amps*2 rails)Watts. I have run the amp for 18 hours and can still touch the heatsinks. The botom is aluminum plate and the feet are solid aluminum blocks.

 

[JCoffey]

What kind of wattage RMS is it pushing?

 

[MikeW]

More than 10 less than 20. Enough to fill the living room.

 

[MikeW]

Boards

The mini-2 boards are due in Monday. I will try to mail them out on Tuesday. If you haven't sent me a shipping address in the last month please E-mail it.

 

[roddyama]

Hi Mike,

What brand/voltage 220uf caps did you use?

 

[MikeW]

http://www.chemi-con.com/files/KMEKMEH9.pdf

KME50vb221

 

[MikeW]

Checked boards

The first set of the mini-2 is up and running. No problems with the board. Built as an Aleph 3 (30), +/- 25 volts. One set of outputs @ 2 amps bias. More listening tests tomorrow.

 

[Mark A. Gulbrandsen]

Received your boards today Mike and they look great!!!!!
Do you think it'll hold up as a 3 with just one set of outputs? That seems like it might be pushing it a bit.

I took my Ver. 1 Mini over to a friends house today that has never heard an Aleph before and I think he was a bit blown away by it. Interestingly he has a set of Coral Speakers.....very interesting. So he's going to be the first out here to build a 3 from your new version 2 PCB.
Mark

 

[MikeW]

Only 50 watts per MOSFET.
They are de-rated @ 1.5 deg/watt over 25 and good for 190 watts. I figured 78 watts max @ 100 deg C case temp.
It may not sound good and end up with more outputs.
It has some good heatsinks.

 

[Mark A. Gulbrandsen]

I don't think the number of outputs would have anything to do with the overall quality of the sound....less is actually better...just worried about how far you're pushing those devices. There are 4 OP devices per chan. in the 3 for good reasons.
Mark

 

[MikeW]

hot

It does run a little hot, but sounds good. My other A-30 has 8 outputs per channel. I have 20 more MOSFETs for replacements. We'll see how long it lasts. Good thing there is a ten year replacement on the test speakers.
Good luck building.