Is this amp specs worth of making PCB?

[MilanAudio]

Hello to all,

just basic question:
Is this amp specs worth of making PCB or it will be just wasted time?

- SNR 110 DB
- freq. response 20 Hz to 20kHz +- 0.5db
- chanel separation at 1kHz 65dB
- 1 channel 80W at 6ohm speaker, dynamic power 117W
- based on SanKen
- band width 10 Hz to 40 kHz
- THD 0.008%

Thanks for your opinion!

Milan

 

[avtech]

Do you have a schematic to share so we can see the topology?

 

[analog_sa]

The specs sound like some Jap midfi from the eighties. If so, it made sense to the manufacturer to produce a pcb at the time

 

[MilanAudio]

So, here is the scheme. I guess there is nothing to improve

An externally hosted image should be here but it was not working when we last tested it.

 

[indianajo]

Nothing special, LPT (long tailed pair) input without CCS(constant current source), a VAS (voltage amp stage) without CCS, one output transistor pair. No speaker DC protection. Input RF elimination not shown.
80 w is a little optimistic from one output pair. If the rail voltages are high enough you can get amazing tenth second "dynamic wattages" at the risk of some heating when sitting around idle.
I'd say buy a honey badger kit board (plus optional genuine parts) from the diyaudio store up top in the blue band. The writeup on that is where i learned the names of the circuit features. Or buy a leach, NAD, or parasound clone PCB from *****. More economical, I got a whole blown up PV-4c amp with 130 w/ch (24 hour rating) (2 pairs OT) for $25 on ebay and put $80 parts in it. Output transistors, rail caps, input caps, more heatsink. It had the case, fan, heatsinks, protection circuit, all that expensive stuff. Alternatively check a local repair shop, class AB amps with a transformer are obsolete on the bar band market because they are heavy.

 

[MilanAudio]

Well, complete scheme is here, so I want to build it up with quality thick pcb, best audio caps, etc. I have 2 of AX10 and I like them

But I think building up the mainboard should improve everything. It looks to me as nice relax too. And honestly, I am tired of researching the right latest, updated, perfect scheme. And Yamaha has really nice sound.

Because I know I'm dummy with schemes (not able to find mistake in scheme), I always need to be sure that desired scheme has no issues. All what I want is simple excellent audio amp with max 100W per channel (min 60w p./ch.).

Scheme - Service manual

 

[jaycee]

Will you be building it with the original transistors shown in the design? If not, then you are building a completely different amplifier. Unless you REALLY want to have a go at designing your own layout, I would say go for something already well done here, such as the Symasym or one of ostripper's amps

 

[JMFahey]

The specs sound like some Jap midfi from the eighties. If so, it made sense to the manufacturer to produce a pcb at the time

You get the Sherlock-Audio-Holmes prize of the day

 

[dhaen]

The mid-fi and even some hi-fi amps of that time and often suffered from poor slew rate. Thus they had impressive specs. but disappointing sound.

Suggest you build a modern design with modern semiconductors.

 

[MilanAudio]

Will you be building it with the original transistors shown in the design? If not, then you are building a completely different amplifier. Unless you REALLY want to have a go at designing your own layout, I would say go for something already well done here, such as the Symasym or one of ostripper's amps

Hmm. I will give a try for symasym. I will hear if it is that impressive. I have lots of audio grade caps so it will be better to use them before they get thick dust layer.