LME49830 + IRFP240/9240

qusp,

What is the best available diy design, so far, that is based on the LME498XX (and, I assume, lateral mosfets)? I would like to build one.

I could start from just a schematic, if everything was fully-specified. I can do PCB layout and fabrication (two-sided), and am usually not completely satisfied with anyone else's layout, anyway. But I guess I wouldn't mind buying someone's PCB, if it was for the best design available. I could always make a new layout later, anyway, and build another one.

I see that panson_hk has done a lot of work with the LME chips. And I see that he has a website with kits, etc, but that many of them are out of stock. Is there perhaps a new "best" design being developed or discussed, right now? In what thread? I need to get up to speed.

Or, if there is something better, I'm all ears. I need something that will drive my Magnepan speakers. So it would be good to have it be able to do at least 100 W into 8 Ohms. A little less should be OK, but 250 W into 8 Ohms would be ideal. And it must be able to drive 4-Ohm loads.

Regards,

Tom
 
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Owens version IMO 'the wire' with Lateral Mosfets. I dont believe you will find a need for redesign. you may find some PCB by putting a WTB in the for sale area here. you will need to make your own power supplies (needs separate ~10v higher supply for front end/LME so it can swing all the way to the rails)

I may also consider letting go of a couple of my PCBs that I was saving for later, need to think on that though. As you can see, the decoupling and layout is up to snuff, probably even you will approve ;)

here are some crazy measurements with DPS600 Audiopower fully regulated power supply from post 1115 onwards.

there were a few teething problems running the DPS600 starting up directly into full 600mA bias in the previous measures, these have nothing to do with the amp, more a matter of converting this supply for use with the higher bias and higher voltage (for the AUX FE supply). with lower bias there was no problem at all

there are measures with unreg for the main outputs and linear reg for the FE earlier (perhaps on the first pages) and the build manual is very nicely done. its a simple schematic, with nicely laid out PCB and very high quality parts, what more can we ask for?

It will handle your power requirements without a problem, it will drive 2ohm loads if you like.
 
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qusp,

Wow. Thanks so much. I had not seen those plots, yet. They ARE extremely impressive. (I would like to see for a very low frequency, too, though.) Knowing me, I would probably investigate further and find some improvement to make (which I would share, of course). I do have some good test equipment, plus access to MUCH more.

It's a little ironic that now that I have finally found something that I really think is worth having, the main parts are no longer available.

I am quite distracted right now. I need to get to the hospital to see my Dad. Otherwise I would start inquiring about finding boards and a DPS600. Please think about what it might take to convince you or someone else to part with a couple of PCBs. In addition to dollars, perhaps I have some unobtainium that you would like. I have a lot of older Tektronix stuff, and parts for them, since I used to refurbish and resell them. I guess maybe I'll have to work on AP2, as well <smile>. Or maybe I'll luck out and someone else will have some that they are willing to part with. But it will have to wait until later.

Thanks again, for your very-informative posts.

Regards,

Tom
 
OK Tom, youve got me interested, bribery will get you far ;) i've already got 4 channels and was saving the 3rd pair for possible Sub duties, but I can perhaps get away with Class D for Subs. i'll shoot you an email/PM and perhaps we can work something out.

also meant to say, hope everything is OK with the Old Man, i've seen enough of the inside of hospitals this last couple of years with my Mother and now Dads possibly in troubled waters too, so I feel for you.
 
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Know anyone with a spare DPS600?

I was thinking this could also be a good time to try out my ideas for a home-made 4-layer "board sandwich". I have a lot of leftover one- and two-sided 0.031-inch FR4 pcb stock. It should greatly-simplify the layout and might even make it possible to improve the already-stellar transient response, while also making it less susceptible to RF.

Of course, i don't have much spare time these days, and also tend to try to be lazy. And ready-made boards would be good to have as a baseline, even if I did want to try making my own.
 

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2005-11-18 1:01 pm
crete
OK Tom, youve got me interested, bribery will get you far ;) i've already got 4 channels and was saving the 3rd pair for possible Sub duties, but I can perhaps get away with Class D for Subs. i'll shoot you an email/PM and perhaps we can work something out.

also meant to say, hope everything is OK with the Old Man, i've seen enough of the inside of hospitals this last couple of years with my Mother and now Dads possibly in troubled waters too, so I feel for you.


qusp did you build the wire (or anybody else?)i didn`t read all the huge thread but haven`t find any reviews.
 
yep, well what more is there to say about a completely transparent and authoritative poweramp? if there was a lot to say it would speak more of coloration. Some manufacturers will add coloration to an amplifier so that the reviewers can have something to say about it, but here we have an amp that lives up to its name, wire with gain. nuff said ;)
 

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Member
2005-11-18 1:01 pm
crete
yep, well what more is there to say about a completely transparent and authoritative poweramp? if there was a lot to say it would speak more of coloration. Some manufacturers will add coloration to an amplifier so that the reviewers can have something to say about it, but here we have an amp that lives up to its name, wire with gain. nuff said ;)

That`s a good thing.
i hope it`s that good.