100W Ultimate Fidelity Amplifier

[apexaudio]

I have up graded some parts with (I hope) better ones available on local suppliers. It is hard to find audio grade parts in my small city (I live in Solo-central Java).
I use some nichicon caps, wima, and sanyo.
If I have no mistake, I have a better low, mid and high now. Much punchy bass ...Crisp high and clearer mid.
I use a snubber PSU with 4X 10.000 uf/63 V. It needs larger heat sink. This amp uses temporary casing until does not up grade again. So interesting amplifier.
With regulated PSU maybe it will sound better.
My skill is poor, so I don't know about any measurements. I will leave it to the expertise.
Again thank you Mr Mile S. I do appreciate your advices for making this amp getting better.
Warmest Regards,
Arif B

Do you use any protect on this amp?
Regards

 

[apexaudio]

AX17S

AX17 with DC Servo circuit.

 

[AndrewT]

5532 seems an odd choice for a DC servo.
Why?

Why an inverting DC servo followed by an inverter?
Could a non-inverting servo do an equally good job?
Why?

 

[apexaudio]

5532 seems an odd choice for a DC servo.
Why?

Why an inverting DC servo followed by an inverter?
Could a non-inverting servo do an equally good job?
Why?

Yes, non-inverting single OP can be use, but I like old 'marantz SM6'...

 

[AndrewT]

why?

 

[irwanks]

Hello sir, Mje 340 and 350 without heatsink, is it ok? Should i add small heatsink for mje?
Thank you.

 

[apexaudio]

Hello sir, Mje 340 and 350 without heatsink, is it ok? Should i add small heatsink for mje?
Thank you.

It's OK, MJEs work in class A with 6mA, but you can add small heatsink.

 

[apexaudio]

Suply for NE5532

 

[Arif Budiyanto]

Do you use any protect on this amp?
Regards

Not yet, I have an old speaker protector, can I use it? Or should I build new one. I have your protect schematic already. If it is a must I will try to build one. I really need your advice.
Thank you in advance.
Best Regards,
Arif

 

[irwanks]

It's OK, MJEs work in class A with 6mA, but you can add small heatsink.

thank you sir for your reply. God bless You

 

[apexaudio]

Not yet, I have an old speaker protector, can I use it? Or should I build new one. I have your protect schematic already. If it is a must I will try to build one. I really need your advice.
Thank you in advance.
Best Regards,
Arif

You can use it, any protect will be better than nothing,
Regards

 

[gooseneck]

To Sir Apex.

Sir good days to you...can you share pcb with AX17S...? thankking you in advance

tnx...benny

 

[RSK]

AX17S pcb

Just a simple contribution.

 

[apexaudio]

AX17S

Just a simple contribution.

Thank you for this pcb design.
Regards

 

[apexaudio]

AX17S V2 pcb

 

[JOHN BALI]

AX17S V2 pcb

Hi Apex,
What is the difference with AX17 for the sound,
is this one has a deeper bass?
I'm not make the AX17's PCB yet, maybe its better a lot AX17S
or better I make the AX17 first & add servo latter?

Regards

 

[apexaudio]

Hi Apex,
What is the difference with AX17 for the sound,
is this one has a deeper bass?
I'm not make the AX17's PCB yet, maybe its better a lot AX17S
or better I make the AX17 first & add servo latter?

Regards

Amplifier must be neutral in sound, for deeper bass use speakers with deeper bass or 'loudness' circuit if you must.
No need to use servo, match transistors and add pot for set DC offset, with DC servo it's easyer (auto set).
Regards

 

[gooseneck]

RSK thanks for sharing the PCB design...and to sir APEX also....

 

[DIDULUS]

Hi Mr APEX, i dont understand the utility of the pair Q3/Q5 (Q6/Q8) instead of only one transistor.... can you explain me?

 

[apexaudio]

Hi Mr APEX, i dont understand the utility of the pair Q3/Q5 (Q6/Q8) instead of only one transistor.... can you explain me?

Q3/Q5 are used for 1mA CCS, Q7/Q8 are used for cascode circuit.