DAT-heads Digest #630, Volume #7 Wed, 12 Oct 05 11:50:00 EDT Contents: MIC2496 and microphone current draw (Clark Guy) problems with Tascam dual dat (tom groff) Re: M-Audio's MicroTrack 24/96 ("Onno J.R. Bakker") SCMS Stripper ("Mallon Stephen-W17525") FS: pair of AT 8410a shock mounts (Dave Maley) Foo Fighters- Patriot Center- Fairfax, VA 10-10-05/9:30 Club 10-16-05 ("Brian Dowling") ---------------------------------------------------------------------------- From: Clark Guy Subject: MIC2496 and microphone current draw Date: Tue, 11 Oct 2005 11:27:08 -0500 Hi, everybody! Just want to clarify to everyone that I'm not complaining about the MIC2496. It sounds really good, and works very well with my self-powered mics (Nakamichi CM-300s). The TOAs pull around 8mA each, if I recall correctly... it wasn't a problem for my home-brew mic preamp, but it is mains powered, and has a relatively large DC/DC converter module in it (about 75% of the size of the MIC2496 itself!) Has anyone any comments about using a pair of Octava MK-012s for location recording of symphonic music (band and orchestra). How about their current draw? Thanx! Guy > In my case, with the MIC2496, my TOA-KY mics pull the voltage down to > less than 9VDC, and drain the battery in minutes, rather than hours. > The TOAs pull too much current for the DC/DC converter in the MIC2496. > Mics that draw less current will have a higher voltage seen on the > lines. Mic2496 is designed to provide up to 4 milliamps total of 48 Volt phantom power. That's more than enough for the large majority of microphones. Its voltage will not drop below a nominal 48 Volts as long it is not asked to provide more than its specified current. If you see the voltage drop, it means that your mics require more current than it can supply -- you should not use those mics with Mic2496 unless you power them from an external Phantom Power supply like our new 2Phant. In contrast, MicroTrack 24/96 was designed to provide only 30 Volts with no load, a rather odd voltage for phantom power -- no other manufacturer that I know uses that voltage. And when loaded even lightly, its voltage drops rather dramatically. Len Moskowitz Core Sound www.core-sound.com Home of PDAudio ------------------------------ From: tom groff Subject: problems with Tascam dual dat Date: Tue, 11 Oct 2005 10:54:18 -0700 (PDT) "you could not put a 90m tape in. every other time you put a 60m tape in you would get an error message." I have the same problem with my tascam dual dat. The local shop never fixed the problem. They told me it was because i used dds instead of dats. Which is not true, happens with both. Even maxell and Tascam tells that to them. Of course. Tom __________________________________ Start your day with Yahoo! - Make it your home page! http://www.yahoo.com/r/hs ------------------------------ From: "Onno J.R. Bakker" Subject: Re: M-Audio's MicroTrack 24/96 Date: Tue, 11 Oct 2005 23:06:45 +0200 Most studio condenser mikes need fantomepower of 48 volts (+-4 volts) conform specs IEC 268-15/DIN 45596 and consuming average 2.5 miliamps (fi Neumann km184 2.3 ma) In a well designed mike pre amp this is accomplished conform IEC 268-15/DIN 45596 with two resistors of 6.8 kohm. (xlr 2 and 3 are going each via 6.8 kohm to stabilised 48 volt + and xlr 1 shield goes to 48 volt -) The value of the resistors is 6.8 kohm because that value does hardly affect the 20h to 20khz audio and is still ok in terms of voltage dropping. If a mike is connected to the preamp the voltage on the xlr 2 and 3 drops from 48 volts to 39.5 volts due to the voltage drop over the resistors. (48 - 0.0025 x 3400 = 8.5 volts) In fact the mike is running on 39.5 volts completely within the specs of the mike. This means that the minimum voltage to feed the xlr must be 39.5 volts to in case the resistors are 0 (zero) ohm. This is only possible with transformer preamps. 39.5 volts on the midtap brings 39.5 volts on xlr 2 and 3 without affecting audio. (the transformer has hardly any dc reactance) But most transformer preamps are using 2 resistors of 6.8 k ohm to xlr 2 and 3 to avoid magnetisising current in the transformer. This all means that to be within the IEC 268-15/DIN 45596 specs the voltage on the xlr with a decent condenser mike connected may drop to 39.5 volts and not lower. So if the M-Audio MicroTrack does not do that and gives only 30 volts (Len sais so) WITHOUT a mike connected it is far out of what a decent condenser mike needs. I cannot believe that M-audio has made it so !! Can somebody confirm this ???? I rather believe that there is something wrong with the mikes. Onno Bakker Rotterdam, The Netherlands ------------------------------ From: "Mallon Stephen-W17525" Subject: SCMS Stripper Date: Tue, 11 Oct 2005 17:51:34 -0400 Is there a relatively inexpensive way to defeat SCMS - less than $100? I have two Sony decks (A6 and DTC-ZE700) and am trying to make digital backup copies of my personal DATs. I'm looking for an add-on device rather than modifying the decks I have. ------------------------------ From: Dave Maley Subject: FS: pair of AT 8410a shock mounts Date: Tue, 11 Oct 2005 21:58:53 -0400 Howdy folks. I have a pair of AT 8410a shock mounts I'm looking to sell. They're in perfect functional condition, only have a few cosmetic nicks and scratches. These typically go for $50 a piece - I'm looking to get $50 for the pair. Contact me off-list if interested or w/ questions: http://www.audio-technica.com/cms/windscreens_mounts/59ffe32bf2065ffb/index.html Peace, Dave -- "Can't get enuff of that wonderful Duff." ------------------------------ From: "Brian Dowling" Subject: Foo Fighters- Patriot Center- Fairfax, VA 10-10-05/9:30 Club 10-16-05 Date: Wed, 12 Oct 2005 00:15:26 -0400 I was unable to make it down to this show as planned. If anyone taped this show DAT, video etc, please drop me an email off list. I have many masters for trade. Also if anyone has an extra ticket, for the free radio show (DC101) at the 9:30 Club on Sunday, please drop me an email, I'd be happy to go and tape it for someone:) Brian ------------------------------ ** FOR YOUR REFERENCE ** To unsubscribe from this digest, please send email to dat-heads-unsubscribe@datheads.phish.net If your email address has changed, you may (optionally) send the message to dat-heads-unsubscribe-oldaddress=olddomain@datheads.phish.net and the old address will be removed. Problems or questions about a subscription should be addressed via these avenues and then if needed to dat-heads-owner@datheads.phish.net or postmaster@datheads.phish.net never the list itself You can submit a message for inclusion in the next digest via this address: Internet: dat-heads@datheads.phish.net Archives of DAT-Heads digests and related files are available on the DAT-Heads home page: http://www.solorb.com/dat-heads/ End of DAT-Heads Digest ******************************