SYMEF amplifier

[OnAudio]

Originally Posted by drowranger

I will build your amp. as soon as i get there.and also I have finished sloan class A pcb and will compare both of them.but right now all I can do is prepare the board.anyway whats best of your amp.is its free and we have your guarantee its working.

Originally Posted by Nico Ras

I will make an attempt at yours after our summer holidays kick off in less than a month. Thank you.

Hi Sam,

The pictures will be here soon. Even the cat is in on it

[drowranger]

Originally Posted by OnAudio

Hi Sam,

The pictures will be here soon. Even the cat is in on it

your coupling capacitor seems very large 100uf.i have search on internet seems all plastic casing and polyester type very bulky 43mm x 24mm.silver mica if there is will be very expensive.can i use two tantalum capacitor in series like sloans technique.I'm preparing the board and listing for what parts i will use.

cheers,
joel

[OnAudio]

Originally Posted by drowranger

your coupling capacitor seems very large 100uf.i have search on internet seems all plastic casing and polyester type very bulky 43mm x 24mm.silver mica if there is will be very expensive.can i use two tantalum capacitor in series like sloans technique.I'm preparing the board and listing for what parts i will use.

cheers,
joel

Hi Joel,

You could even scale C8 from 100uf to 10uf. C6 from 2200uf to 100uf . The Slone technique is also fine by me. Nice progress

kind regards

[Nico Ras]

I am curious now. Have you actually built this amp and does it work. Show us some pictures of the layout as it could have some significance impact especially with the low current that you chose.

Also since it is so important to follow the circuit, more important is to get the power supply absolutely perfect.

Power supply is the most important part of an amplifier and you do not even make mention of it. Wiring is equally important so it would be great to see how you constructed yours so that everyone is on the same page.

If you need answers that has any relevance to your design it must be specified down to the wire size and length, PCB track sizes, components type and manufacturer, board layout and material, else your 30K answers will be just that, 30K answers referenced to nothing, you may as well generate 30K random answers and chose an outcome that fits you predictive software precisely.

Good luck

[OnAudio]

Originally Posted by Nico Ras

I am curious now. Have you actually built this amp and does it work. Show us some pictures of the layout as it could have some significance impact especially with the low current that you chose.

Also since it is so important to follow the circuit, more important is to get the power supply absolutely perfect.

Power supply is the most important part of an amplifier and you do not even make mention of it. Wiring is equally important so it would be great to see how you constructed yours so that everyone is on the same page.

If you need answers that has any relevance to your design it must be specified down to the wire size and length, PCB track sizes, components type and manufacturer, board layout and material, else your 30K answers will be just that, 30K answers referenced to nothing, you may as well generate 30K random answers and chose an outcome that fits you predictive software precisely.

Good luck

Hi Nico,

The model assumes the PCB is perfectly laid out. This is one parameter that is not tracked in the model. This design uses an unregulated supply unless where indicated. It will be interesting to find out how the design holds up to the varied component types, manufacturers, PCB s and power supplies. Then we will let the computer grind the numbers.

I currently do not have any pictures. I am hoping to have a demonstration unit sometime next year. Or who knows one of the diyers much like it so much that they might reward me with one.

kind regards

[Nico Ras]

I have yet to come across a perfect PCB, or an unregulated supply of some predictable performance specification at least. Components vary to the extent that you see in these threads that claim is made that models are incorrect. Here is an interesting little story:

A man in a hot air balloon realised he was lost. He reduced altitude and spotted a man jogging below. He descended a bit more and shouted, "Excuse me, can you help me? I promised a friend I would meet him half an hour ago, but I don't know where I am."

The man below replied, "You are in a hot air balloon hovering approximately 30 feet above the ground. You are between 40 and 42 degrees north latitude and between 58 and 60 degrees west longitude."

The balloonist thought for a moment and replied: "You must be an engineer," said the balloonist.

"I am," replied the man, "but how did you know?"

"Well," answered the balloonist, "everything you told me is technically correct, but I have no idea what to make of your information, and the fact is I am still lost."

The man below responded politely, "You must be a statistical manager."

"I am," replied the balloonist, "how did you know?"

"Well," said the engineer, "you don't know where you are or where you are going. You made a promise which you have no idea how to keep, and you expect me to solve your problem. The fact is you are exactly in the same position you were in before we met, but now, somehow, it became my fault."

[drowranger]

also the coil and output transistor location.onaudio pls check my work for possible mistakes specially my schematic.I got confused on your capacitor has no polarity should be electrolytic cap.

cheers,
joel

[OnAudio]

Originally Posted by drowranger

also the coil and output transistor location.onaudio pls check my work for possible mistakes specially my schematic.I got confused on your capacitor has no polarity should be electrolytic cap.

cheers,
joel

Hi Joel,

I took a quick peek . R8 should be 12 Ohms. Relocate R13 and C1 to speaker side. C6 could be replaced with two 220 uF or you can use a protection diode. Or go non polar with film types .

kind regards

[drowranger]

Originally Posted by OnAudio

Hi Joel,

I took a quick peek . R8 should be 12 Ohms. Relocate R13 and C1 to speaker side. C6 could be replaced with two 220 uF or you can use a protection diode. Or go non polar with film types .

kind regards

i have check sloan schematic you mean a 1n4146 in parallel with c6.and the zobel after the coil.ill get in touch with you saturday we have no work on friday and no internet in my room.thanks for checking ill change it tonight when i get back in my room.going home.

cheers,
joel

p.s. i will try it on jbl4311.

[OnAudio]

Originally Posted by drowranger

i have check sloan schematic you mean a 1n4146 in parallel with c6.and the zobel after the coil.ill get in touch with you saturday we have no work on friday and no internet in my room.thanks for checking ill change it tonight when i get back in my room.going home.

cheers,
joel

p.s. i will try it on jbl4311.

Hi Joel,

R8 on your schematic not R7. Nice speakers. Use ceramic for high frequency feedback. I see you have used a polarized symbol for all capacitors ?

kind regards