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Rockbox mail archiveSubject: RE : my facts on micsRE : my facts on mics
From: Henri David <hdavid_at_mail.com>
Date: Mon, 21 Oct 2002 21:17:11 +0200 Well as i said, if you leave the gain to zero while recording, and instead use an external amp it's ok. I have the feeling that the build amp amplify more electronic noises than the actual signal... henri > -----Original Message----- > From: owner-rockbox_at_cool.haxx.se > [mailto:owner-rockbox_at_cool.haxx.se] On Behalf Of Justin Fisher > Sent: Monday, October 21, 2002 8:57 PM > To: 'rockbox_at_cool.haxx.se' > Subject: RE: my facts on mics > > > I think I've noted this before, but I don't imagine everyone > saw - I rerouted the line-in wires in my recorder through the > battery compartment, thus shielding them from the archos > circuitry and HDD (the wires are unshielded and travel the > length of the case, right up against the circuitry). This > resulted in the removal of the interference from the archos > operation and disk spins. Hopefully later model recorders > have shielded wires now, but if you can hear interference in > your recordings that corresponds with HDD spins, shielding or > rerouting the line-in wires seems to be an easy and fairly > effective fix. > > -----Original Message----- > From: Henri DAVID [mailto:hdavid_at_mail.com] > Sent: Monday, October 21, 2002 2:04 AM > To: rockbox_at_cool.haxx.se > Subject: RE: my facts on mics > > > hello, > > I tried the Sony ECM 907 with the archos. you need a preamp. > I made one using one of those http://www.velleman.be/ kits + > two 9v batt. http://www.velleman.be/Product.asp?lan=1&id=8982 > I put it in a plastic box with one on/off switch in in and out plugs. > > The quality is ok as long as you leave the amplifier level to > 0 on the archos. (this integrated amp is way to loudy if you > increase the gain !) you can check the quality of what I get > there : > http://www.cs.helsinki.fi/u/tkt_davi/photos/2002-04/13-labas/l > abas01-LQ.mp3 > http://www.cs.helsinki.fi/u/tkt_davi/photos/2002-04/13-labas/l > abas02-LQ.mp3 > http://www.cs.helsinki.fi/u/tkt_davi/photos/2002-04/13-labas/ > (I reencoded them in lower quality, for internet purpose, but > can still get an idea about the quality) don't pay attention > to the saturation, that was my fault I set the level to and > didn't reduced it ! (BTW Archos Firmware VU meter are quite > precise as they showed me the clips !) > > > Hope it helps > > henri > > > > > > -----Original Message----- > > From: owner-rockbox_at_cool.haxx.se > [mailto:owner-rockbox_at_cool.haxx.se]On > > Behalf Of Uwe Freese > > Sent: Saturday, October 19, 2002 14:24 > > To: jimg > > Subject: my facts on mics (was: Microphone) > > > > > > Hello jimg, > > > > jimg wrote on Saturday, October 19, 2002, 12:58:07 AM: > > > > j> You're mixing apples and oranges here. The battery for the > > j> microphone provides -phantom power- to drive the > condensor; It does > > j> not > > "amplify" > > j> the signal coming out of the microphone. This mic is a > pro-level > > j> mic, > > > > I think this is also wrong. Three possibilities: > > > > - dynamic mic, this mic doesn't need power > > - electret condenser: this capsule has a FET inside and > needs power > > (>1,5V). Mony mics of this type exist, and they usually > have a battery > > inside. This power is not for amplification! > > - condenser: this type needs the phantom power (48 V). This > also is not > > for amplification. > > > > Amplification: > > > > - dynamic mic has a greater output volume > > - both dynamic and condenser mics need an amplifier to > connect them to > > the AJB line in, but maybe different types > > > > "Mic boxes": > > > > - many of them only provide the battery power. No amplifier > inside. But > > sold for much money. :( > > - What I want (for ajb) is a box that > > - gives the power for an electret condensor capsule / mic > > - amplifies > > - needs only a battery (9V) > > - I soldered this type with a simple operational amplifier > > and this costs < 5 ? > > - one can built better boxes with better amplifier ICs > inside (see the > > german magazine c't 20/02, page 228, ~ 100 ?) > > - minidisco.com: I think they are very expensive and I > don't think that > > these battery boxes are worth the money > > > > Mic types: > > > > See > http://arts.ucsc.edu/EMS/Music/tech_background/TE-20/teces_20. html > > I think the best for recording a concert would be a one-point stereo > mic with mid-side technique. And the Sony ECM 907 is the cheapest > I've seen (~ 100 ?). > > Bye, Uwe. > > Received on 2002-10-21 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |