My Sure IRS2092 Amplifier Build

[hongrn]

Re: My Sure IRS2092 Amplifier Build

One last addition to the amp that, IMO, is worthwhile mentioning. The fan noise, although minimal, was bothering me, because it was constantly running at full speed. I added a simple circuit consisting of a IRFZ24N MOSFET transistor, a 10K trimming pot, and a 10K thermistor (total $6). The thermistor is inserted between the fins of the heatsink, and adjustments to the pot ensure that the fan only turns on when the temperature reaches between 110 and 120F. And when it's on, it runs very quietly, never at full speed. After 4 hours of operation, the heatsink never got above 120F, and the fan noise barely perceptible.

Hong

[PWR RYD]

Re: My Sure IRS2092 Amplifier Build

Nice looking work but I think your fan cooling would be more effective if it was on the finned side of the heat sink.

[hongrn]

Re: My Sure IRS2092 Amplifier Build

Craig, completely agree with you. That will be part of the planning in the future, on where all these components go, instead of my current band-aid approach. But then, I've got another excuse to build another amp, don't I, until "perfection" is reached?

Nice looking work but I think your fan cooling would be more effective if it was on the finned side of the heat sink.

[devinkato]

Re: My Sure IRS2092 Amplifier Build

Beautiful - I'm in the process of investigating power supplies for a smaller/less powerful amp module - the TDA7297. I was impressed with this module in it's stock form, and tossed on some upgraded components, and have been totally blown away. I like the sound/size a lot, and have decided that it deserves a dedicated PSU and enclosure.

I'm trying to learn, but I don't even know where to start! All of my experience has been with the cheapy switching mode power supplies, which I've been told are vastly inferior to other options. Can you suggest any starting point for me to take my knowledge to the next level?

[kanemack]

Re: My Sure IRS2092 Amplifier Build

so my question is what kinda cash and tools does it take to build one? the tools i have mostly anything to fix anything. money wise, i have no idea.

[hongrn]

Re: My Sure IRS2092 Amplifier Build

You can start right here. There is a lot of basic information for those who don't have an electronics background (like me):

http://www.decdun.me.uk/gainclone_psu.html

Beautiful - I'm in the process of investigating power supplies for a smaller/less powerful amp module - the TDA7297. I was impressed with this module in it's stock form, and tossed on some upgraded components, and have been totally blown away. I like the sound/size a lot, and have decided that it deserves a dedicated PSU and enclosure.

I'm trying to learn, but I don't even know where to start! All of my experience has been with the cheapy switching mode power supplies, which I've been told are vastly inferior to other options. Can you suggest any starting point for me to take my knowledge to the next level?

[hongrn]

Re: My Sure IRS2092 Amplifier Build

Depends on how much power you want. The most expensive items are the case and transformer. I'm going to start building wooden cases like Bob Cottiers to cut the cost down. You can buy used transformers for cheap if you hunt the classified sections of diyaudio, or shop at ApexJr. Other than that, a good soldering station, DMM, LCR meter, Googling skills, and a good dose of respect for high voltage electricity. As I said, this amp cost me less than $300.

so my question is what kinda cash and tools does it take to build one? the tools i have mostly anything to fix anything. money wise, i have no idea.

[robertcottiers]

Re: My Sure IRS2092 Amplifier Build

Hong: You will certainly save money by building the wooden case, I would love to see what you come up with !

In spite of the frigid weather here in PA I have already started building 3 more Amp cases...I have gotten used to working in 10-15 degree weather(with garage door open) :D.....I would type more but my frostbite is killing me.

Regards
Bob C.

[hongrn]

Re: My Sure IRS2092 Amplifier Build

That's called dedication Bob. It's been raining cats and dogs here, but I'll take the rain over the snow anytime. That reminds me of the time I landed in Sharon, PA on a business trip years ago (a group of crazy docs contacted us to help them develop a surgery center), the weather was around 9 degrees. My ears fell off my head...

Hong: You will certainly save money by building the wooden case, I would love to see what you come up with !

In spite of the frigid weather here in PA I have already started building 3 more Amp cases...I have gotten used to working in 10-15 degree weather(with garage door open) :D.....I would type more but my frostbite is killing me.

Regards
Bob C.

[neildavis]

Re: My Sure IRS2092 Amplifier Build

I would type more but my frostbite is killing me.

If you need some good news about the cold, apparently the stinkbugs are also getting frostbite: http://www.washingtonpost.com/blogs/...va-tech-study/

[[email protected]]

Re: My Sure IRS2092 Amplifier Build

ApexJR has a bunch of stuff at great prices. My order should be here middle of the week. I will be using 16 of these for my next build. http://www.apexjr.com/images/4700uFChemecon.JPG Just $1.75 per.

[robertcottiers]

Re: My Sure IRS2092 Amplifier Build

If you need some good news about the cold, apparently the stinkbugs are also getting frostbite: http://www.washingtonpost.com/blogs/...va-tech-study/

[ATTACH=CONFIG]45201[/ATTACH]

Hi Neil:
I did see that story a few weeks ago, They are very acclimated to the the cold weather but I guess the prolonged single digits have put them at a tipping point...RIP

It's a balmy 25 degrees, So I'm heading out to the garage right now,I have to take advantage of this warming trend !

[Ron_E]

Re: My Sure IRS2092 Amplifier Build

The amp is based on International Rectifier's AMP7S design, which is scalable with tradeoffs that can be made for supply voltage and power output and load. The Sure amp is closest to the Amp7S-200, but different values have been selected for the OVP, UVP and current trip levels. You can use the following table to help you figure out how far you can "push" the amp with a given power supply. A word of warning, tho.... Sure has been known to change components in their products, so your amp may not be the same as mine. The values in the column on the right were from an amp I bought over a year ago, and the components in current-production amps may not be the same.

Since the OVP is 91V on the AMP7S-200 could I use one of these boards with a PS that puts out slightly more than 70V? I have an old Leach 250W amp that died but has a big toroid PS that's still good.

Ron

[hongrn]

Re: My Sure IRS2092 Amplifier Build

Since the OVP is 91V on the AMP7S-200 could I use one of these boards with a PS that puts out slightly more than 70V? I have an old Leach 250W amp that died but has a big toroid PS that's still good.

Ron

Ron,

Here's a quote from the PE site from an owner of the amp. I think this will answer your question:

What is the maximum Voltage?

I bought the 800Va dual 45 Volt secondary transformer from Avel, and built my own power supply for this amp. I am getting +/- 68 VDC on the rails. With the supply connected to the amp and the AC power to the transformer on, the amp will not turn on. Once I turn the AC power off and the voltage drops a little the amp turns on and stays on until the caps drain down to a lower voltage. The amp seems to only operate between 55 and 65 VDC. Is this where the over and under voltages are set? I thought the over voltage would be somewhat higher than the recommended max voltage.

[hongrn]

Re: My Sure IRS2092 Amplifier Build

I still have a bunch of those. Steve Slater's store is half an hour from my house, so I'm like a kid in candy store when I go there. Are you building another IRS2092 by the way?

ApexJR has a bunch of stuff at great prices. My order should be here middle of the week. I will be using 16 of these for my next build. http://www.apexjr.com/images/4700uFChemecon.JPG Just $1.75 per.