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.
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.
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 was not working when we last tested it.
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.
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
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
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
.
Just for the guys with poorer monitors. The initial A700
An externally hosted image should be here but it was not working when we last tested it.
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.
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.
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Sorry to hijack your thread...I should go reading in the relevant forum.
I wish I had the money to build an Aleph 4. I see the same DIY-GENE site sells an aleph 5 kit. Did you find an Aleph 4 kit somewhere? I see the 4 has more devices; what are the gross performance charactistics of each?
I'm very interested in a personal investigation of some high-end amps. I've listened to class-A amps like the Mark Levinson, but I've never lived with one, nor have I ever had a chance to do A/B listening comparisons. Speaker charactistics instantly leave an impression on me; amplifier audio signatures are much more difficult for me to identify beyond basics like power output. My dad's Citation I and II are very "musical" but the power limitations and tube microphonics and other thermal and socket noises are irritating. I'd like to live with a few more powerful solid-state class-A amps for a while and see how I like them.
I wish I had the money to build an Aleph 4. I see the same DIY-GENE site sells an aleph 5 kit. Did you find an Aleph 4 kit somewhere? I see the 4 has more devices; what are the gross performance charactistics of each?
I'm very interested in a personal investigation of some high-end amps. I've listened to class-A amps like the Mark Levinson, but I've never lived with one, nor have I ever had a chance to do A/B listening comparisons. Speaker charactistics instantly leave an impression on me; amplifier audio signatures are much more difficult for me to identify beyond basics like power output. My dad's Citation I and II are very "musical" but the power limitations and tube microphonics and other thermal and socket noises are irritating. I'd like to live with a few more powerful solid-state class-A amps for a while and see how I like them.
My Aleph 4 has cost me about £200 GBP so far. A lot of patience and waiting on E-Bay. Most of that cost for one transformer that I had to buy new (even that was redundant stock). I risked buying the IRFP244s from E-Bay, they're genuine and cost me £24. If you read my thread you will see how it can be done for a song.
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