Explendid amplifier designed by Michael Bittner, our MikeB

[anatech]

Yes.

 

[PMA]

Second attempt: Hoephoephoep.

Jacco,

as you know, you are too skillful in insinuation 😉 .

Cheers,
Pavel

 

[dfdye]

After trying to skim 300+ pages of this thread, I am finally throwing in the towel and asking if there is a WIKI or other guide for the Symasym that I can read to get up to speed? I HATE to be "that guy" that jumps into the thread and asks "how does this work again?" after 300+ pages of answers to just that question, but I was trying to find the current state of the amp to see if I wanted to build one and have just gotten lost. I know the original version was getting great reviews, but if I wanted to build one I want to do it with the latest update.

Thanks, and sorry in advance for being "that guy."

David

 

[Greg Erskine]

Have you looked at these:

http://www.lf-pro.net/mbittner/Sym5_Webpage/symasym5_3.html

http://web.telecom.cz/macura/symasym.html

 

[dfdye]

I have now. This is exactly what I was looking for.

Thanks!
David

 

[Chuck911]

Case

bremen nacht: My friend sent me a link for you and anybody else who can be interested in cases.

http://www.audiobox.sk/index.php?option=com_virtuemart&page=shop.browse&category_id=15&Itemid=26

 

[kubedes]

starting procedure

there is somwhere in this thread starting procedure
did someone know where it is.
MikeB described step by step starting procedure _ what to do staring sym for the first time - what to check and how. AFIK it was about version 5.2

😕

i have first monoblock assembled but the fuses are blowing. i have 2,5A fast ones.

i've checked PCB three times - everything looks OK.

tkank you for help 🙂
Piotr

EDIT
only positive rail fuse is blowing.
i'll try to bypass them with 100 R resistor

 

[kubedes]

First monoblock works fine 🙂

I've checked all the board again, reassembled it with wires and it started. 😀

I have in PS 25V/300VA toriod and 22 mF Sprague (Big Can) Elyt for each channel.

Drivers - 2SC3298/2SA1306, power trans. - 2SC5200/2SA1943 Toshibas.
Rest of transistors as on Mike site. Carefully matched.

DC on output 3,5mV 😎

Second channel tomorrow (hope so 🙂 )

The only thing is the "buzz" (brum) from speakers.
How to avoid it?
Pictures soon.

Greetings
Piotr

 

[pinkmouse]

Well done! Which PCBs did you use?

The only thing is the "buzz" (brum) from speakers.

Careful layout of parts, attention paid to routing of wiring, and good grounding. It may take several attempts. 😉

 

[kubedes]

I have not connected VGND on board.
Have no idea where to connect. To trafo ground?

Sym is build "on wood" - its just board. No case.

😕

 

[pinkmouse]

It needs to be connected somewhere. Do you have a star ground point?

 

[kubedes]

Which PCBs did you use?

I've used boards made locally (borys) in Poland taken from MikeB site.
Amp is playing. Will take pictures tomorrow, during the fight with "buzz"

Thank you pinkmouse. 🙂

Piotr

 

[kubedes]

I have not connected VGND on board.

It was very late yesterday.... 🙄

VGND is to be connected to PS GND point. I have symmetrical PS (double bridge).

That how it looks like (for now)

 

[kubedes]

PIC

 

[kubedes]

Board

 

[Upupa Epops]

How I see, devices are little sottish...wodka Wyborova ? 😎

 

[loek]

Pic

Kubedes, do you use only one big powersupply capacitor?
I see there are 2 smaller ones on board.
So there is maybe the "buzz" problem?
good luck,
Loek

 

[jacco vermeulen]

Vodka Wyborova ?

Da, a take dva, pozaluysta

A SEmaSEm maybe ?

 

[kubedes]

Re: Pic

How I see, devices are little sottish...wodka Wyborova ? 😎

What you mean "sottish" ?

 

[padamiecki]

Re: Re: Pic

What you mean "sottish" ?

pochy³e, zobacz jak przykrêci³eœ trany wyjœæ.