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DIY-GENE A700 Mark Levinson Clone
DIY-GENE A700 Mark Levinson Clone
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Old 27th May 2011, 11:45 AM   #1
Andy5112405 is offline Andy5112405  United Kingdom
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Default DIY-GENE A700 Mark Levinson Clone

Having built one of these "Clones" I have a few words of warning.

The design is very robust and the build quality is good. However, the DIY spirit is poor and the supply very poor.

My A700 Kit arrived from Hong Kong wrapped in newspaper and sheets of cardboard. The amplifier boards come pre-assembled and tested, they also arrived pre-stressed and most of the transistors bent well away from their natural angle. Several of the power transistor leads had broken away from their PCB lands, however, the PCB had mercifully not been damaged. Several of the taller capacitors had been punctured and two of the small ceramic caps had disappeared (OK the legs were still there) - All down to the appaulling packaging.

After a bit of cajoulling, DIY-GENE replaced the faulty components. They were nice enough about the whole polava but after spending many hundreds of pounds on the kit I was anxious to get it going.

Don't expect any technical help from these guys, it just aint forthcoming.

The kit I received was supplied with SIL-PAD insulators and was biassed at 1.26A.

The supplied heatsinks are completely incapable of operating at these levels. After a few days of operation one channel detonated (literally blowing transistor fragments around the amplifier).

As a minimum, throw away the SIL-PADs and invest in MICA and GOO. Even this resulted in excessive heatsink temperatures. I eventually had to crank down the bias to 1.0A (ie Class AB operation at high volume) in order to maintain any sort of reliability.

OK, I didn't spend the extra cash on purchasing the recommended 42-0-42V transformers, mine are 45-0-45V.

It is an excellent excellent sounding amp (yes I meant to say that twice) but be careful of the SOAR of the output transistors. I have the Motorolla Upgrade - another 80 above the asking price.

An externally hosted image should be here but it no longer works. Please upload images instead of linking to them to prevent this.


Don't bother with the Capacitor Boards as it is far easier to just connect the capacitors banks together with copper bar.

I used 6 x 33000uF per Channel and flattened 8mm Copper tubing.
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Old 27th May 2011, 01:30 PM   #2
ByronInPortland is offline ByronInPortland  United States
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Hi Andy,

Thank you for the warning to everyone considering buying from this vendor. I'm glad you got it working and are happy with the results in the end! It looks like a real professional build in the photo.

Please edit your post with a much smaller photo. The photo is so big that only a small part can be seen on an average monitor, and it takes a long time to load.

-Byron
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Old 27th May 2011, 01:44 PM   #3
Andy5112405 is offline Andy5112405  United Kingdom
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Although the two amplifiers share the same Real Estate, they are completely separate. The only common connection is the Mains Input, after that they are completely separate.
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Old 27th May 2011, 01:57 PM   #4
Andy5112405 is offline Andy5112405  United Kingdom
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I have never heard of a set-up where the amplifiers are supplied from two different power stations.
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Old 27th May 2011, 04:08 PM   #5
poynton is offline poynton  United Kingdom
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Quote:
Originally Posted by ByronInLawrence View Post
.......................
Please edit your post with a much smaller photo. The photo is so big that only a small part can be seen on an average monitor, and it takes a long time to load.

-Byron
Agreed !!!

I wish members would post using the inbuilt facility NOT photobucket etc.

I'm still waiting for the huge picture to download while I have written and posted this message.


Andy

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Old 27th May 2011, 04:19 PM   #6
stoolpigeon is offline stoolpigeon  Australia
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great idea using copper tube!

sp
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Old 27th May 2011, 06:40 PM   #7
Andy5112405 is offline Andy5112405  United Kingdom
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Just for the guys with poorer monitors. The initial A700

An externally hosted image should be here but it no longer works. Please upload images instead of linking to them to prevent this.
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Old 28th May 2011, 01:03 PM   #8
poynton is offline poynton  United Kingdom
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.............. or use the attachment facility and it will remain on the forum for ever - not disappear in a few weeks!

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Old 18th June 2011, 10:39 AM   #9
Andy5112405 is offline Andy5112405  United Kingdom
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Default FOR SALE - DIY-GENE A700

Now that I have finished my Aleph 4 I have no requirement for the EXCELLENT DIY-GENE A700 that preceeded it.

Please note that I have removed the 12 x PSU Electrolytics and the 4 x 25A Bridge Rectifiers. Other than that it is 100% comlete and ready to go.

Supplied with full schematics. This unit is the upgraded version of the A700 with the Motorolla MJ21193 and MJ21194 power transistors.

Fitted with 2 x 500VA 45-0-45V Transformers - both have dual primaries and can be used for 115 or 230V operation.

Item weighs around 30Kg so postage is going to be HIGH.

I'm looking for 100. That's worth it for the transformers alone. The case is in excellent condition and the amplifier modules are both fully functional and tested.

Last edited by Andy5112405; 18th June 2011 at 10:43 AM.
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Old 18th June 2011, 01:53 PM   #10
cyclecamper is offline cyclecamper  United States
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Sounds like an exceptional deal for someone local.

So you prefer the sound of the cascode aleph?
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