{"id":1220,"date":"2003-11-04T11:14:00","date_gmt":"2003-11-04T18:14:00","guid":{"rendered":"http:\/\/www.sheer.us\/wordpress\/?p=1220"},"modified":"2003-11-04T11:14:00","modified_gmt":"2003-11-04T18:14:00","slug":"things-for-sale-and-power-amp-thoughts","status":"publish","type":"post","link":"https:\/\/www.sheer.us\/weblogs\/uncategorized\/things-for-sale-and-power-amp-thoughts","title":{"rendered":"Things for sale and power amp thoughts"},"content":{"rendered":"<p>So one of the recent advances in power amplifiers is switching power supplies. I find this interesting because most switching power supplies will &#8216;eat&#8217; DC just as happily as AC.<\/p>\n<p>The question is, will modern amps run directly off my car&#8217;s traction pack without the need for inverters? This could substantially increase the amount of power output I could achive if I were using my car for (hypothetically) power during a party.<\/p>\n<p>Right now I&#8217;m limited to about 3kW continuous by the limitations of the DC\/DC converter. If I could run amps directly off the traction pack, the only theoretical limit becomes the energy stored in the traction pack &#8211; 10kW is only doable for 2 hours, for example.<\/p>\n<p>On the other hand, a PA stack rated 10kW is seldom _drawing_ 10kW &#8211; because the only time the transistors are actually conducting massively is during the heavy bass notes or kick drum beats.<\/p>\n<p>It might be possible to do 8 hours of audio at 10kW, given the power consumption ratio<\/p>\n<p>10kW would seem to me to be about the target output for a outdoor show. <\/p>\n<p>(And I&#8217;m 1500W closer to it today thanks to the wonders of E-bay)<\/p>\n<p>Let&#8217;s see.<\/p>\n<p>Output capacity online: <\/p>\n<p>1400W in the subs<br \/>\n3300W in the mains (with new additions)<\/p>\n<p>Total: 4700W. Halfway there. \ud83d\ude09<\/p>\n<p>I need to find a party that needs sound, to test out my latest additions.<\/p>\n<p>In other news, I&#8217;m trying to get rid of a motorcycle. Anyone in Seattle want a motorcycle that doesn&#8217;t run? $100, you pick it up or use my shop facilities to clean carbs and change battery after which you could probably drive it home. Full disclosure: needs carbs cleaned, new battery, new left shock, new front tire, new right mirror. 750CC, twin, with shop manual and clear title. 10k miles.<\/p>\n<p>Also, anyone need a folding e-bike? Again, doesn&#8217;t run (on batteries.. you can pedal it and it&#8217;s got a 3-speed transmission) &#8211; it could almost certainly be repaired since it&#8217;s only obvious problem is the motor mount is bent but it might need other things too. This one is free to the first person to come pick it up.<\/p>\n<p>Also, is anyone interested in buying a gas board scooter? $600\/obo, ran good the last time it was started (6 months ago), heavily modded with custom deck, exhuast resonator, extra big air intakes. I&#8217;ve never driven it so I can&#8217;t say how it performs.. it was collatoral on a loan that was never repayed. If there is any potential interest I can get model number, pictures, things like that.<\/p>\n<p>Anyone want a rolling 19&#8243; rack? This is the old-skool SKB rack that held 12U on the bottom and a 18U mixer (would fit the Alesis studio 32, several other 16-channel mixers). This is the style with two big wheels on the back and two casters, good for going up and down stairs and other offroad activities. I still have all the body plates for it. $35.<\/p>\n<p>Or, how about a Digitech Vocalist MIDI Vocoder? This I&#8217;ll probably e-bay off unless someone is interested &#8211; I&#8217;ve done many good and creative things with this beastie, but I upgraded to a TC Helicon for lead pitch correction and whatnot, and it does so much more. $100<\/p>\n<p>Any takers for a Midiman USB\/serial to 8X midi adapter? Drivers for every OS you could name. $100, cosmetically perfect, electrically perfect, I replaced with a MTP AV because I needed better clock control<\/p>\n<p>How about a roland SC-880 sound module? Great drums, great strings, $200<\/p>\n<p>Last but not least, is anyone interested in some monitor speakers.. electrovoice ported 10&#8243; with high-compression horn tweeters &#8211; one of them has minorly damaged high frequency driver (no longer performs as well as the other one). $50 (this is a kickass price, for this you can well afford to replace the blown driver from MCM electronics and still be way cheaper than the $200 these would cost you new). Program capacity: 100W RMS &#8211; and they aren&#8217;t kidding. \ud83d\ude09 [Hence the damaged driver &#8211; I hooked &#8217;em up to a 900W RMS amp, then someone cranked up the keyboards and damaged]I&#8217;ll even through in some 1\/4&#8243; speaker cables to get &#8217;em hooked up to your amps.<\/p>\n<p>S. [who is trying to get some of this CRAP OUT OF MY BASEMENT! ARGHHHH!!]<\/p>\n","protected":false},"excerpt":{"rendered":"<p>So one of the recent advances in power amplifiers is switching power supplies. I find this interesting because most switching power supplies will &#8216;eat&#8217; DC just as happily as AC. The question is, will modern amps run directly off my car&#8217;s traction pack without the need for inverters? This could substantially increase the amount of [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/www.sheer.us\/weblogs\/wp-json\/wp\/v2\/posts\/1220"}],"collection":[{"href":"https:\/\/www.sheer.us\/weblogs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.sheer.us\/weblogs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.sheer.us\/weblogs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.sheer.us\/weblogs\/wp-json\/wp\/v2\/comments?post=1220"}],"version-history":[{"count":0,"href":"https:\/\/www.sheer.us\/weblogs\/wp-json\/wp\/v2\/posts\/1220\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.sheer.us\/weblogs\/wp-json\/wp\/v2\/media?parent=1220"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.sheer.us\/weblogs\/wp-json\/wp\/v2\/categories?post=1220"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.sheer.us\/weblogs\/wp-json\/wp\/v2\/tags?post=1220"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}