Mrboo's Diy "gainclone" Amplifier

[Silverfox]

Listening tests are pretty subjective.

It's a lot easier if you have several pieces of equipment to compare, then you notice all the differences more.

 

When we were getting rid of some CD players (we had too many ) from the house a while back, I plugged them all into my system to make sure they still worked and it certainly opened my eyes to how different things can sound.

 

Ended up keeping the old NAD player for my room because it sounded so good.

 

i inherited one of these - kenwood for

[markiemrboo]

i inherited one of these - kenwood for

[jammin]

Right, I just remembered that I said I post some pics of the inside of my Arcam Alpha 10P.

So here they are. I'm a man of my word after all

 

There are obviously similarities to your DIY amp, as they basically perform the same task.

I'll let you read into any differences as I don't know much about the components.

 

From the outside

 

And the insides

 

 

I thought you might be interested in the caps. U.S. Made, which I found interesting.

Edited December 22, 2006 by jammin

[Andrewr05]

Quite alot of space on that left side isnt there?

[markiemrboo]

Right, I just remembered that I said I post some pics of the inside of my Arcam Alpha 10P.

So here they are. I'm a man of my word after all

 

There are obviously similarities to your DIY amp, as they basically perform the same task.

I'll let you read into any differences as I don't know much about the components.

 

From the outside

 

And the insides

 

 

I thought you might be interested in the caps. U.S. Made, which I found interesting.

 

The way they've mounted the toroid on to the PCB is much more interesting

 

The differences are actually quite huge, in that I have started really simple and used an IC from NS (LM3886) (a.k.a chipamp), which really is basically just a massive opamp. I can't do a huge PCB either, so it had to be done 'modular'... which in a way I prefer. But anyway, so long as it sounds good who cares!

 

Quite alot of space on that left side isnt there?

 

It looks like space for a pre-amp or something.....

 

 

I did actually get that sheet of mirror perspex. It looks so strange inside now! You look in to it...... and it's..... just like a mirror! I *still* don't have a camera, but you can just about tell / see reflections from webcam pictures.

 

 

I also got hold of an oscilloscope from my uncle (which is insanely fun to play with). The shape of a simple sinewave does have slight differences from my current amp. It's pretty impossible to tell from the picture, but everyone loves an oscilloscope display

 

 

What I find odd is that with one speaker on the new amp, and one on the old amp, playing music downmixed to mono and fading between the speakers there's bugger all difference that I can hear (though it's probably not the best of tests, the downmixing might be messing with it, or even just the fact it's one speaker at a time). But!!! I'm using this amp now, and I could swear it does sound different. It's just seems so much easier to listen to, even at the highest of volumes <_<

 

 

 

Next up I am building a pre-amp (as the Cambridge preamp is slightly hissy, like *very* quiet white noise coming from the tweets), and a 'turn the power on when an input signal is detected' thing Both of these are from Rod Elliot (There's no way I am clever enough to design these myself, I don't understand enough!), I have just drawn the PCB myself again. They'll look something like this:

 

pre-amp

 

 

signal power on

 

 

 

I just need to get my arse back down to staples to get the artwork photocopied

Edited December 22, 2006 by markiemrboo

[jammin]

Pictures of the inside of my Musical Fidelity Pre-Amp as well?

 

(it just gives me an excuse to take things apart really )

Edited December 22, 2006 by jammin

[markiemrboo]

Pictures of the inside of my Musical Fidelity Pre-Amp as well?

 

(it just gives me an excuse to take things apart really )

 

go for it matey, if it keeps you busy / happy might aswell I think Mr Fox mentioned your preamp to me, he said it was a tiny little cool looking box?

[kingdingeling]

lookin good markie!

 

funny how only Unforgivin and Andrew have posted in here as non-UK members

So that thing is putting out some good stuff?

[markiemrboo]

lookin good markie!

 

funny how only Unforgivin and Andrew have posted in here as non-UK members

So that thing is putting out some good stuff?

 

 

Certainly is! It's actually only ever so slightly quieter than my other amp (~40WPC vs 60WPC). Apparently you need 10x more power for just twice the volume (i.e 1W to 10W, then 10W to 100W, then 100W to 1000W etc).

 

I also want to DIY a pair of speakers too My cutting skills are terrible though, and reasonable (/very good?) quality drivers are sort of expensive (about ~

[jammin]

DIY speakers would be interesting.

Also somewhat more difficult to put together well I imagine.

 

Anyway, here are some pics of my pre-amp.

 

 

[markiemrboo]

DIY speakers would be interesting.

Also somewhat more difficult to put together well I imagine.

 

Anyway, here are some pics of my pre-amp.

 

 

 

I hear Musical Fidelity and Arcam are supposed to be really good, you have some nice stuff ( but I am sure you know this )!

 

The traces on the top layer of that PCB look quite... interesting! Especially in the middle section, where it's all curvy! Those light blue caps looks strangely similar to the ones [that used to be] in my Cambridge. They don't have "R.M" written on them by chance (probably not)?

 

I think I prefer the idea of having a separate pre and power amp, rather than integrated. Takes up more space but... I like modularness Have you tried different preamps? If so, did it sound much different?

[jammin]

I believe the Arcam was paired with the Croft valve pre-amp (which is part of the main system in our living room) for a short period.

It's too long ago for me to remember the differences in the sound though.

 

I know it does make a difference however.

My father was a bit mad on hi-fi stuff not so long ago (with detriment to other things might I add), so we have all kinds of crazy stuff in the house,

which includes all kinds of cables and accessories (I don't like to think about how much they cost).

Mosey on over to Russ Andrews and you'll get the idea.

 

The Musical Fidelity pre-amp is around 20yrs old I think, so it's held up pretty well considering.

 

Oh, and the empty space in the Arcam is so a third 100w channel can be added.. there is a bit more about that Here

 

And if you like modularness (nice made up word ), then you could look at monoblocks. Probably a bit expensive though.