Gainclone building thread based on BrianGT's boards

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so far i guess i've got the head start on everyone. all the resistors and chips are soldered up on 4 channels. got myself a gigantic case to fit everything in, found around a dozen heatsinks to play around with, and only waiting on the transformers and caps that i ordered today from parts express. since brian and meredith were so generous, i will also be able to build another 2-ch setup (probably be the first one to be done). if i can scrounge up some caps from the electronics recycling center here on campus (where the heatsinks and case came from) maybe i can have this thing going veryyy soon
 

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tpenguin said:


...And yet he still won't sell me any of the nice ones. He must be must be saving them for another imaginary project ;).

I forgot to count the ones that I am leaving in the cabinet at school ;) But those already have all the metal cut out for a chassis, which is the perfect size for the mini-a, so I definately can't sell those ones.

--
Brian
 
Peter Daniel said:


It might be too much, especially if you add 750VA transformer's regulation factor. Just build supply and check DC voltage, it shouldn't be more than 40V.

OTOH, what are you gonna do with all those heatsinks you are buying, after you try GC?;)


BrianGT said:


He will save them for the 200watt+ bridgeclones that he wants to build in the future for his 7 channel amplifier.

--
Brian

Well I still have two finished Aelph 5 Boards, 2 finished Aelph 2 boards, 2 finished AV800 boards, 2 Finished PZ4 boards and a few Aelph-X boards yet to poulate!!!
 
lets see if i can get some more people in the spirit of building these things. a struck gold today at the parts center. found me a toroid out of an older electronic test equipment thing that gots dual 22 secondaries (my first toroid too). also snagged some 2200uf 35v caps to hold me over til parts express gets here. so figured i'd post a few more sub-par quality pics of the work in progress. this one includes the transformer i bought from apex jr a while ago (it'll get used for something one of these days), the newly discovered toroid trans, and my first gc board with today's salvaged caps. now just waiting (no rush though, take your time) for Brian's build instructions (just to make sure i'm 100% right in hooking these things up) and i'll be up and going with at least a stereo pair (the 6-ch will wait til i can get some good connectors)
 

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I've completed soldering the components to the pcbs. I haven't done any soldering in 20 years, but things went pretty well. I was worried about burning the chip when I soldered the negative feedback resistor, so I clamped the chip and resistor together on a 1/2" copper plate that I have down in the basement. this weekend I'm headed to You-Do-It Electronics this weekend to round out my supplies (wire, speaker posts, inputs...). I plan on starting with cheaper parts and then upgrading as time and $ permits.

widman
 

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Note:

I included a basic resistor set with about 2/3 of the pcb set orders (not kits) as a bonus to help those get started building their gainclone. Here are what they values are:

4 - small blue resistors - 22.1k ohm
2 - small blue resistors - 220 ohm
2 - brown resistors - 680 ohm

The small blue ones are the compact 0.5w metal film resistors, and the brown one is a 0.5w carbon film. These were chosed to be cheaper substitutes for the premium resistors.

If you didn't get them with your kit, here are the part numbers:
4 - 22.1k ohm resistor (min quantity = 5)
Digikey: PPC22.1KXCT-ND
2 - 680 ohm resistor (min quantity = 10)
Digikey: P680BBCT-ND
2 - 220 ohm resistor (min quantity = 5)
Digikey: PPC220KXCT-ND

They should all be in stock from Digikey.

The manual will be available soon. Sorry for the delay.

--
Brian
 
Listening to it

I got my other channel thrown together, checked for any dc on the output and then tested on the spare NHT, all is good. So, I moved it over to the B&W Nautilus 805s, using a Philips 963SA as the source.

Very good sound quality. Sorry, but I can't begin to describe sound in the way that Stereophile, WhatHiFi, et al do. Never the less, I don't hear any real flaws. The bass may not be as good as I think it should, but I am still in the prototype stage. I only have a 2x14 150VA transformer, I'm waiting on a proper one from VM. And this is the "standard grade" parts version I built first to make sure I wanted to invest more into it. The wire is all Radio Shack 20 gage stranded, and the input is one of those cheap Sony interconnects they (used to) throw in with their components.

Hm, maybe the bass is pretty damn good, just got to a better track on "A momentary lack of reason." Pulled it out and stuck in DSotM, straight to "Money." Very good sound!

The only problem with this amp is my 4 month old daughter is asleep in the next room :)

David
 

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Re: Listening to it

net-david said:
I got my other channel thrown together, checked for any dc on the output and then tested on the spare NHT, all is good. So, I moved it over to the B&W Nautilus 805s, using a Philips 963SA as the source.

Very good sound quality. Sorry, but I can't begin to describe sound in the way that Stereophile, WhatHiFi, et al do. Never the less, I don't hear any real flaws. The bass may not be as good as I think it should, but I am still in the prototype stage. I only have a 2x14 150VA transformer, I'm waiting on a proper one from VM. And this is the "standard grade" parts version I built first to make sure I wanted to invest more into it. The wire is all Radio Shack 20 gage stranded, and the input is one of those cheap Sony interconnects they (used to) throw in with their components.

Hm, maybe the bass is pretty damn good, just got to a better track on "A momentary lack of reason." Pulled it out and stuck in DSotM, straight to "Money." Very good sound!

The only problem with this amp is my 4 month old daughter is asleep in the next room :)

David

Looks like you got a good start. What are you planning on using for your chassis when you get around to using the good parts?

--
Brian
 
I got my sound approximate 5:30 Pracfic time. One Word "Beast" it is loud as hell ! It even louder than my Old IGC that I assembled b4. THe bass definately tighter and louder than my IGC. Treble still good. :D If I have this setup (this NIGC + my bookshelf speakers) and play music like 75% of the full volume in HK at night. I will be complained by 8th-10th floors above me. hehe:D
 
Dear Fellows, I must say that I start very late this hobby, I would like to share with you my first attempt to build a NI-GC (using Peter D schematics, plus a CAP in the input) I did work very well (This is my first project ever), actually looks very messy. Thanks to Brian and its nice PCBs now I am going to build a couple of them (prettier that my first one). In the lower part of the picture you can see an alternative way to put the NFR. Sorry for the language

Thank to Peter D and Brian B

PHR
 

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Yet another Transformer question:
I have some transformers that have just 2 wires from the secondary. Ijn other words they don't have plus minus and neutral . Just plus and minus.


Can I use one transformer of these per channel?

I think that that you need a plus, and minus and neutral ground for each channel.
I'm gonna look at the schematic but would like some backup.

Edit: Looks to me like you need AC plus, minus, and neutral from the transformer? i.e. 3 wires; even for just one channel? right?
 
Rarkov said:
It should only drop like that if the mains are disconnected because the capacitors drain though the multimeter, down to ground. It should be extremely slow since VMs are designed to have a high input impedance.

Not sure what the problem is but double check your wiring.

Good luck,
Gaz
So if it do drop slowly, then I''m fine right?
 
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