EEVblog Electronics Community Forum
General => Buy/Sell/Wanted => Topic started by: IO390 on December 05, 2014, 01:41:59 pm
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So I recently put some of these up for sale: https://www.eevblog.com/forum/buysellwanted/some-really-tiny-50w50w-amps-for-portable-speakers/ (https://www.eevblog.com/forum/buysellwanted/some-really-tiny-50w50w-amps-for-portable-speakers/)
And people seemed happy with them. I've had some requests to build some more, so I've done another batch. It's the same size, but has full L-C output filters to help reduce EMI output. Due to the inductors being used, I didn't have room for screw terminals, so they were replaced with 100th headers. You can either just use normal female header sockets for low power applications, although I recommend simply soldering to the connectors.
They sound nice, great detail and very clear. They have tighter bass than the previous version with ferrite beads, which had a "deeper" sound. But this is certainly an improvement I think, and I've been using one instead of main amp (which is about 10x the size and weight). Anyway, I'm offering it with either 20dB or 32dB gain. the 20dB option has slightly lower rolloff, and seemingly better detail but I can't be sure. I'd recommend the 20dB option for home use, and 32dB for portable speakers.
Please note, as I didn't make it clear enough in the previous thread, that one must not expect 50 "usable" watts. At this power level, the THD rises enormously, and is basically unusable. However, one can expect 10 real watts (8 ohms) without problems. This is plenty for most normal applications. For more info, please consult the TPA3132 datasheet.
Also, it does actually run fine on 5V. Don't expect much power output though.
To make things easier, they are available (with full specs) at my bigcartel shop: http://io390.bigcartel.com/product/25w-amplifier-v2 (http://io390.bigcartel.com/product/25w-amplifier-v2)
Some pictures:
(http://i.imgur.com/U7ttKIul.jpg)
(http://i.imgur.com/ZVyHQuKl.jpg)
(http://i.imgur.com/2UxlYSwl.jpg)
Some size comparisons:
(http://i.imgur.com/9Lb58xnl.jpg)
(http://i.imgur.com/sf4imJGl.jpg)