Perhaps a big cause of the cost up is all those OSCONs? I agree, looks very nice. I prefer SMT though.
No SMT here except for the IRS2092 itself which sits beneath the board.
That looks very nice. Only $8? I don't know if buying from Taobao is easy though. Now that I have an account in Aliexpress it is pretty easy. Always free shipping.
SMT allows the shortest paths and lowest stray capacitances and inductances I guess. The parts are also cheaper than thru hole. I just have to use binocular magnifiers though.
The title amp is all SMT except for the main mosfet.
These are the same board by LJM (check the engraving of the figure on the PCB)
I guess you are right. These boards used to cost < 200 RMB. The Oscon probably bump up the price.
It is interesting that you mentioned that. LJM (he has a thread on this amp in this forum) mentioned that he purposely designed this board not using SMD but thru holes and ran into a lot of problems. Obviously he solved all the issues. He does have a few other IRS2092 boards that use mainly SMD and cost more, not cheaper!
Buying direct from TB these day is fairly straightforward. Anyway, these boards are on sale on EBAY too, but watch out for copy cats. Recently, I found that for ane item that is on sale on EB, Aliexpress and TB, the listed price are very similar (taking exchange rate into consideration). Used to be cheaper on TB, not anymore. Thus, not much initiative to buy from TB now. I like to buy from Aliexpress too.
Regards,
Having looked at the DS - its a self-oscillating design and operates single ended. The ICs (TPA3116, TDA7492) are clocked designs and they operate bridged. Seems to me its rather a big challenge to get a self-oscillating design to work in bridged - even nCores aren't bridged.
So lack of bridged means the design needs to have balanced rails.
So lack of bridged means the design needs to have balanced rails.
Some ICEPower amps are designed as bridged, and are self-oscillating. Example: 200ASC.
Though with that Abeltec supply at that price, I can't see much reason to worry about needing dual rail.
Has anyone mated this amp with the Abelec? I have about 6 of the supplies squirreled away, haven't tried any yet.
Though with that Abeltec supply at that price, I can't see much reason to worry about needing dual rail.
Has anyone mated this amp with the Abelec? I have about 6 of the supplies squirreled away, haven't tried any yet.
Thanks for that, I shall study the schematic to see how they do it. Its here - http://www.diyaudio.com/forums/clas...-engin-not-complete-finished.html#post1957813
My Abletecs should be here in a few days so I will test and report back. I really could use a 200w power resistor. Maybe some lightbulbs can work - need at least 4ohms though, preferable 8. Otherwise testing 200 w on real speakers is noisy work.
Lightbulbs are highly nonlinear as loads. You could use some single cup beverage heaters in parallel - I got one to test as a dummy load from a '2 yuan' shop nearby, it measures about 50ohm but I'm on 220V. Seeing as you'll be on 110V if you get some of these they'll be (assuming the same 1kW rating) about 12ohms, so three of them in parallel should be able to handle any amp you care to buy.
<edit> I had a quick look on Amazon for an example but mostly the mains powered ones are 300W which is too wimpy. There are some in-car ones but I can't see any wattage rating for them.
<edit> I had a quick look on Amazon for an example but mostly the mains powered ones are 300W which is too wimpy. There are some in-car ones but I can't see any wattage rating for them.
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Hmm. The "specs" on the amp (such as they are) say "8A" max. So it will give only 200W at 4 ohm load (before..? Limiting, exploding?), so hold back on the drive when running the Abeltec and 4ohms with it. The 56V supplies could give current peak of 16A.
I need another amp like I need a hole in my skull... dammit.
and then, there's http://www.aliexpress.com/item/YJ-IRAUD350-700W-4ohm-Mono-Audio-Power-Amplifier-board-Class-D-AMP-board-Assembled-Amp/32288184432.html
and then, there's http://www.aliexpress.com/item/YJ-IRAUD350-700W-4ohm-Mono-Audio-Power-Amplifier-board-Class-D-AMP-board-Assembled-Amp/32288184432.html
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Pretty tempting... will the Abletec drive this one OK? I need this amp!
only $30 for a 750w amp?