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Hm, unless you are a solder pro (and maybe you are) I would not mess with those boards. The chips are sensitive and adding those caps may be doing more harm than good. Especially on the bottom of the board.
Thanks The system run around 2h and i really love it, normaly i'm to be reserved, but form me it is a clear improvement, don't expect such nice sound by change some components. The Elnas really match in my system. But i would say i have well improved and sensitiv system which surface every change.RegardsMarcus
I guess it could be done by everybody who have had some little solder experience. But you need the right tools (solder pin (not to small, around 3mm) , desolder wick, "good old" solder (before RoHS ) ).Prepare is the key.Pins of the Capacitors :My issue is, i have only two hands But for me it helps to do it in following steps:Make one pad of the target position free (desolder wick) and put some solder to the other pad.Now fix the capacitor to that pad by heat up the solder on the pad (solder iron in one hand) and positioning the capacitor (in other hand) .. after that it is easy to put some solder to other "free" pad, because capacitor is already in place.RegardsMarcusPS : Sorry my english is not the best Hopfully some one could understand and imagine.
If possible also update the PS Caps of THAT1200 and IRS2092 with higher cap value, low esr types ( I use Panasonic FC).RegradsMarcus
Flying home from California after a brief visit with Tom at Class D Audio. Picked up a new pair of SDS-450 amp boards with improved heat handling capabilities (as well as some other tweaks to the circuit I believe). Great guy, nice tour of the skunk works and a good sneak peek at some upcoming new products.A treat was getting to hear a pair of Polk SDA-SRS speakers (the 2.3TL if I've got the models right) driven by one of his little 254 stereo amps. The bass was incredible and full, rich sound all the way up. Source was simply a lowly Squeezebox Touch through an older looking preamp I cannot recall the make of.Future products? How about a relatively inexpensive 2"x2" amp board with volume control putting out about 15 watts. You can even move a jumper to bridge it for 30 watts. Just hook up a DC power supply anywhere from like 10-24 volts (or something like that, I may have the exact range wrong) or a battery and you're good to go. I'm thinking about a portable cigar box amp. Tom's sample sounded great with an iPod Nano source and a pair of NHT bookshelf speakers.Looking forward to getting my SDS amp boards home and hooked up. Will post pictures once I've got them unpacked.
At the risk of confounding matters for you, I recently contacted Tom about the same thing and ended up settling on a pair of the SDS-450 amps. I think we are using the same speakers... Magnepan 1.6QR. Initially I though I'd start with a single SDS-470 even though it seemed like overkill (though that's never really the case with Maggies). But I wanted to keep the option open to go to a pair of amps for passive biamping or even mono blocks for more power.Here's the response I got from Tom: If you're going to run the amps in bridge mode, I would recommend the SDS-450 kits. They also run cooler and can put about 1000W RMS into your Magnepans. The different models got so confusing with regards to power and price I put together a chart clarifying this for myself, based on what info I could dig up from Tom's site and this thread. Here's what I came up with:ModelSDS-224 SDS-254 SDS-258 SDS-450 SDS-470 Stereo watts 8 ohm60125250150300 4 ohm120250--300600 2 ohm------600800Mono watts 8 ohms240500--600*800* 4 ohms------600*800*Board $235245265245**265**Kit $ w/xfmr285320370350370* Note from Tom: As far as power output in bridge mode the protection circuitry will prevent the amps from putting out more power than they actually could. The SDS-450 will put out about 600W into 8 ohm bridged and about the same into 4 ohm… protection circuit. The SDS-470 is just more power at about 800W bridged.** Not currently listed on website, temporary price as of today 10/17/2011 possibly until this weekend. Will go up about $40 when listed on website. If anyone wants one before they are listed on the website, purchase the SDS-254 or SDS-258 and email Tom with instructions to upgrade to the SDS-450 (for SDS-254 price) or SDS-470 (for SDS-258 price).The SDS-480 kit ($468) and SDS-1000 kit ($498) are simply the 224 and 254 kits with two amp boards and a single HD power supply, respectively.I will send a copy of this to Tom to see if he can verify these numbers and fill in the holes. I know it would make amp selection much easier if this was all available. Verified with notes added from Tom at Class D AudioOh, and I STILL have to assemble my amps and give them a try... maybe this weekend.
Ajani... 450 was on the website briefly, but has not been there recently. Here's some info I posted way back when...
I have two SDS 224 in a single case; post #2368 of this thread. I had planned to use them for Bi-amping an OB system that I built, but plans change and now I am considering running them bridged. Any thoughts? These amps sound wonderful and have been very reliable. No heat issues. Thanks,Bill
Photos of revised SDS-450 amp module with improved heat handling capabilities to prevent premature tripping of the protection circuit. Also applies to SDS-470.Larger heatsink pontoonsResistors mounted off the board to help with coolingThermistor moved towards the rear of the heatsink (small circle in middle of the heatsink at the power input/speaker output end of the PCB), originally at other side of the heatsink between the FETs where it was the hottestHeatsink added spanning underneath PCBTom also mentioned that there was a change to the FET buffers which lie underneath the raised heatsink just behind the FETs.
