30~50w each channel with remote

[jaya000]

I wish to make one 30~50W each channel for friend. My friend is lazy & wants remote control. Due to remote control (MCU & DC volume control) the quality is affected. Hence i will like to know about the good possible solution for amplifier and control circuit. I am thinking of usingLM 3886 with mono pcb & separate powersupply for each channel.

[sangram]

I am lazy too

I use a PC with wireless multimedia keyboard and mouse, put through an E-mu 1212M, to 4x4780 in BPA, to my speakers.

Just the ticket for a lazy audiophool like me

Seriously, the quality is leaps and bounds ahead of anything I have heard. The speakers are a weak link but I'm fixing that.

On topic: For a remote, a good solution would be to implement a relay control system with good quality relays and resistors.

PD is making one now, AFAIK and there are some kits available around.

Or if you have the skill maybe design one yourself.

How many channels are we talking about? It sounds like you're aiming for HT, but I could be wrong.

Some hi-end stepped attenuators are able to accept a stepper motor. Even a good Alps motorised pot will be good but you'll have to figure out a way of controlling it. Can't be too difficult...

Some new vol control chips aren't too bad, you may want to google a bi, or search right here.

[palesha]

I want to make just 2 channel. Hence need to know LM3886 will be better or any other chip.
Regarding control circuit i was looking for separate ideas.
U hv used 4780. How is it?
If possible give more details about ur project.

[DJ Exprice]

Since the amp is going to have a lot of circuitry for the wireless, you may want to try the LM4780 to minimize space consumption in the case.

[DJ Exprice]

This may be of use to you then:

WM8816 digital volume control (WM STAMP)

[sangram]

Originally posted by palesha
U hv used 4780. How is it?
If possible give more details about ur project.

Not bad. Very powerful, but not as much as my neighbor's hammer - they're remodelling, so I can only listen late at night.

I find the system very balanced, doing nothing too wrong. Nice in details, adequate in bass. Nothign shines out at you, but nothing is recessed either. Works best in stock configuration, though I added some big caps in the PS section, my memory seems to tell me the sound at stock config was slightly different, and richer in the midrange.

The project is basically two 4780 dual mono boards from Peter Daniel, I paid about 150 dollars for those, and a couple of custom-wound 22 volt 440 VA EI transformers (Terminated with screw terminals, electrostatic shield). Housed as of now in a wooden drawer pulled from a chest of drawers, but I have some nice custom cases on order.

I also bought some pretty basic 5" heatsinks locally and those are coupled to the chip directly (no mica) with thermal paste. Seems they get to about 80 degrees if I've been belting it out, but in normal use don't go over 55 degrees. So I think the chips will survive.

Amps are wired in pure dual mono, bridge parallel. I don't need a bridging adapter as my sound card operates in fully balanced mode, and the DC offset is about 2 mV on one channel and 5 mV on the other.

I would urge if you have some experience, to try a discrete circuit. The Symasym, Rod Elliots amps, AKSA and the Greg Ball series are all pretty good. A little more complicated than a chipamp, but I would hazard a guess that they sound better, well worth the effort of construction. I just didn't want the hassle, being in a very small flat with nowehere to sleep, let alone keep an amp.

[palesha]

I would urge if you have some experience, to try a discrete circuit. The Symasym, Rod Elliots amps, AKSA and the Greg Ball series are all pretty good. A little more complicated than a chipamp, but I would hazard a guess that they sound better, well worth the effort of construction. I just didn't want the hassle, being in a very small flat with nowehere to sleep, let alone keep an amp.

Hv u assembed / tested or listened to any of the above amps? I hv already made Rod elliot one. but will ike to know more about others for my future project.

Looking at Lm 4780 it seems to be 2x lm 3886 built in one. Hence i think LM 3886 might be better. or if i make 30W each channel 8 ohms then LM 4780 will be ok.
More suggstions r welcome.

[sangram]

TBH, no, not yet, but....

The next project for me is one of the above discrete amps - I find Greg's GB modules very tempting, the price is right but I would not be able to use my transistors (3281/1302) for that project. Still, let's see - this is at least six months away for me.

The reason I used the 4780 was the compact layout, and that you could get a really small footprint for a BPA if you didn't separate the boards. It will be tight fit into a standard 12" depth case, but will fit. 4 LM3886 dual mono boards would not fit into one rack case, and I don't have space for monoblocks.

My next immediate project is a new PC for gaming, that's a big money-sucker. And those L18 boxes - can't find a decent box-maker for the life of me. You would know someone in Mumbai who could turn out a good pair?

HTH

Sangram

[jaya000]

Thanks DJ Exprice for the link!
It seems to be useful.
Also looking for possiblities of discrete amp.

Sangram : U can use 2SC5200/2SB1943 Toshiba pair. It is easily available in aamchi Mumbai.
Mumbai has got instrument box makers. u can buy one from Lamington rd.

[sangram]

Originally posted by jaya000
Sangram : U can use 2SC5200/2SB1943 Toshiba pair. It is easily available in aamchi Mumbai.
Mumbai has got instrument box makers. u can buy one from Lamington rd.

I already have the transistors, in an old HK amp.

I need someone to make speaker cabinets, I already found someone for the amp cases.