SYMEF amplifier

[OnAudio]

Looking good Alex. Nice LEDs.

 

[Tekko]

I used actual 3.3V zener diodos as the only leds that are anywhere close to 3.3V is blue LEDs which to me is just no go, horrible color :/

 

[alex mm]

.... becouse I forgot to order 3.3V Zenner diodes I will use white leds instead , until will have
Thanks for comment ...

 

[AndrewT]

does it need to be 3.3V?
What tolerance on that voltage is allowed?

Could a series pair of IR or red LEDs do the job?
Could a series red LED + a signal diode do the job?

 

[OnAudio]

Optimum 3.3 V however what Alex is using is ok, should drop around 4 V.

 

[OnAudio]

Hi Digger,

For Grounding checkout this quick scheme

http://www.diyaudio.com/forums/solid-state/211977-quick-guide-grounding.html

kind regards,

Harrison.

 

[Krisfr]

Is there a final BOM with Schematic?

 

[OnAudio]

Hi Kris,

Here is one, but everybody has been doing their own thing (I guess makes it more fun)

Amplifier

kind regards,

Harrison.

 

[Tekko]

So i've been listening to a LM3886 amp for a few days, now im back at the SYMEF amp and i believe the symef amp sounds better, its softer in the mids and highs while the LM3886 amp was a bit sharp.

 

[Nico Ras]

Why not use a SMD 3V3 regulator, it is infinitely better than a zener.

 

[Jay]

Dx also uses this formula.

Interesting. It is the only mystery I couldn't solved.

 

[Jay]

So i've been listening to a LM3886 amp for a few days, now im back at the SYMEF amp and i believe the symef amp sounds better, its softer in the mids and highs while the LM3886 amp was a bit sharp.

Comparing any state of the art to an LM3886 is an insult, Tekko...

 

[Tekko]

How so ?

 

[Jay]

How so ?

Amp quality perception is different among the beginners and the experienced. Ability to know if we really want what we think is good is also scarce. I want to see somebody compare the bipolar SYMEF with the LEACH amp. I think OnAudio is on the right track here. Unfortunately I'm not a bipolar fan to investigate it further.

 

[OnAudio]

Nico, you could use the regulator though, that means a larger component count internally. Nico your review and dance? make it happen

 

[OnAudio]

whos ready to post results

Gentlemen and Ladies, there are amplifiers that should be ready now. The list is soo long. You know yourself s.

This amplifier so far has evoked strong emotions, could the formula have stumbled onto something ?

What is your experience with this amplifier, what did it whisper to you in those first notes it played?

Is your search for amplifier over or should we go back to the lab ?

 

[Nico Ras]

The component count remains the same just replace the zener with regulator like the SOT23 style TC1014 from Microchip.

For those who built the amp, besides discussing what it sounds like, the most important parameter that affects the performance of any amp is its power supply.

Be sure to describe your power supply in equal detail since this is the governing factor.

 

[Nico Ras]

Harrison, to get any meaningful subjective result I propose that you tabulate what parameters the listener must use and how it must be graded. Numerical grading may be better than the typical audiophile jargon.

 

[Tekko]

My symef amp is still running on a 2x35VDC psu consisting of two 2x12V 80VA transformers in series.

 

[Tekko]

Heres my idea for a housing for the symef amp, i plan to drill holes in the front in a as nice looking pattern as i can for cooliong air to get in.

This is the only chassi i have that looks somewhat good.
The next best one is the chassi from an old Yamaha Natural Sound Stereo Receiver, but then i will have to find some other heatsinks.