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DIY power amplifier help

Wharfedale Diamond 12 Series

jai1611

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Folks,

I've been thinking of entering the DIY world for some time. I'd picked up two of these kits some time back from ebay: POOGE 2 MOSFET Power Amplifier Kit (Mono)_Integrated Amplifier_Analog Metric DIY Audio Kit Online Store . Had to put the whole thing on hold because of work but am now thinking of taking up the project again. However, I am pretty much a newbie at the DIY side of things and would need a fair bit of help.

Starting off, do the Guru's think that this might be too much of a challenge for a DIY newbie? If yes, I'd appreciate suggestions on what might be a good alternative?

In case I do go ahead with the build, can someone point to suitable power supply boards? The seller told me I'll need +/-30V TO 50V transformer. Any ideas on where to source this and what sort of amperage I'd need?

Thanks in advance,
Jaibir
 

kaushik

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Hey you spent 10k !

seems simple kit .. do some soldering practice on verro board with some dummy components.

before the gurus come here ... some pointers
many CRGO EI transformes you will get in mumbai market ,500VA you may need i think . If you need toroidals,
I am hunting for toroidals too....

go here Toroidal Transformers

and here (toroidal cores only,need to get winding done)
Manufacturing Toroidal Core Testing Toroidal Core Process

ask for sample
 

sarith

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toroidals are good..I like them too..but for the money of one toroidal,I can get two ordinary steel core transformers..checked the mosfet amp..pricey I must say..toshiba mosfet is good...I have used their Bipolar...sounds good...more suited for sub woofer amps..just using 4 transistors in one channel,can supply DC upto 70-0-70 for connecting 4ohm woofer..how did you managed to ship this mosfet amp to india?total cost too pls?
 

GeorgeO

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If you can connect up with someone dependable who is experienced in soldering and testing such circuits, then it may not be too hard to do.
 

jai1611

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Thanks for the help guys.

@ Kaushik, I picked these up on ebay for a bit under 5k in total.

@ Grubyhalo, thanks for the link

@ Cranky, thanks for the tips. Guess I'll start with the basic audiosector chip amp kit. Will revert once I've progressed a bit more on those.

@ GeorgeO, unfortunately I dont have anyone locally who has electrical skills to help out.

I guess the kits are shelved for now. In case any more experienced DIYer wants to try their hand, I'll be happy to pass them on at cost.
 

kaushik

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@ Kaushik, I picked these up on ebay for a bit under 5k in total.
great hunt.. dont worry .for high level tweaks
so might be using oscilloscopes..refer amp builders pics online how they placed PSU .

I am sure if you put proper capacitor bank and trafo .amp will give proper sound!

then learn grounding basics if some hum etc are there..

now make a plan ,
visit youtube for soldering tips
like YouTube - How to Do It: Basic Soldering
get a good iron (soldron is good ,has many fakes), and good solder wire.
 

rikhav

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You can contact Akshay Jha and see if he is ready to take the project and build the amp for you.
His contact number is 9867359109
He has repaired my Cosmic amp and one other member's Sansui amp. Just give him a call and see how things work out. Call him in the evening as i think he does not answer calls when he is at his job
 

sarith

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get a good iron (soldron is good ,has many fakes), and good solder wire.[/QUOTE]

soldron is a nice choice...I have two...one for reserve...if original,soldron can really last kinda life time..soldering is easy once you have learnt it..just remember not to do dry soldering..not too much flux..etc

Citation 12 MOSFET Power Amplifier Kit ref Harmon-Kardon (Mono)_Integrated Amplifier_Analog Metric DIY Audio Kit Online Store

this is a good amp..I don't mind using IR mosfet for the front channels in HT or stereo..this link shows IRFP240(I used 250)..

got robust sound..ultra fast..it won't that easily 'blow-up' if anything goes wrong..good for newbie experiments
 

jai1611

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jai1611

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thanks for the tips Cranky. I have a couple of old speakers handy which would work well for testing and which I dont mind blowing up.

Would the dual mono lm4780 kit do the job for the Dynes? From what I understand, the 4780 is effectively two lm3886 chips (slightly higher power than the lm3875) in parallel
 
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