60 watt design...

[rtill]

Does this look like a good design for a power amp?
http://www.redcircuits.com/Page65.htm

 

[jaycee]

No.. it'd work, thats about all you can say about it.

There's some good circuits on Sam's page: http://users.otenet.gr/~athsam/index.htm

Or theres Rod Elliot's P3A: http://sound.westhost.com/project3a.htm

Or MikeB's SymAsym: http://www.lf-pro.net/mbittner/Sym5_Webpage/symasym5.html

Or Destroyer X's amp: http://users.tpg.com.au/users/gerskine/dxamp/

The last two have PCB designs available which means you won't have to design one. Rod sells a PCB for his P3A amp.

 

[sreten]

Hi,

It is suitable for purpose, i.e. a guitar amplifier, but a very poor hi-fi amplifier.

🙂/sreten.

 

[rtill]

is it possible to change the voltage and output transistors to get 150 watts?

 

[MJL21193]

is it possible to change the voltage and output transistors to get 150 watts?

Hi,
150+ watts here . Compare.

 

[east electronics]

dont you .....

even think about it ....

 

[jaycee]

No. You cannot simply beef up the transistors and increase the voltage - the whole circuit needs to be designed for that. If you want a 150W amp, then go for a circuit designed for it.

 

[rtill]

fire fire fire

so I built this amp 3 times with all new parts each time.....and R4 keeps starting on fire.....what's going on????

 

[east electronics]

i am so sorry

canot really help you since the data you provide is not enough .....

but if you like to have some other smoke producing devices i have a few to point for you .....

ONLY JOCKING !!!! BEST REGARDS SAKIS

 

[Donk]

R4 keeps starting on fire? Then there is something really really bad there!
Is Q2 still alive?

Plase provide us some meaurements as Sakis asked.
What is your rail current consumption? What's your output DC offset?
Any oscillation?
What PCB design did u use?
Etc..

 

[rtill]

using this design.... http://www.redcircuits.com/Page65.htm

power supply transformer is the hammond 165P60

http://www.hammondmfg.com/165.htm

I'm wondering if the transformer is too much for this circuit....

 

[Bobken]

using this design.... http://www.redcircuits.com/Page65.htm

power supply transformer is the hammond 165P60

http://www.hammondmfg.com/165.htm

I'm wondering if the transformer is too much for this circuit....

Hi,

It looks to me as if this transformer secondary voltage is too high for this circuit, if I have read this info correctly.

To end up with around 60VDC for the suggested circuit requirements, when using a full-wave bridge rectifier arrangement like this, the transformer secondary should not be much higher than say 45V AC.

The transformer you specify has 2 x 30V AC secondaries (or 60V centre tapped) which will give you in the region of 80+V DC at the circuit.

In fact it doesn't look as if there is a suitable transformer in that range, unfortunately.

Regards,

P.S. Yes, I just noticed that the specs lower down on the schematic suggest 48 -50V secondaries.