charlie@oakhill.UUCP (Charlie Thompson) (01/04/90)
Anybody out there have experience with the new Ariel Digital Microphone?? What are your opinions of it? For the unaware, Ariel has produced a stereo microphone with two 56ADC16 16-bit A/D converters in the handle of the mic. The output is compatible with the NeXT box (serial digital). It has a little bargraph LED VU meter in the handle as well...cute. Thanks in advance, C.T.
agn@unh.cs.cmu.edu (Andreas Nowatzyk) (01/05/90)
Some time ago, I had a chance to play with it, but the unit in question may have been a prototype or an alpha version, so take the following comments with a grain of salt. Electronically, the unit is indeed cute. It is a bit warm because it consumes a bit more power than you'd like. The LED's are fine and the fidelity from electrical signal in to digital out is probably ok (golden ear audio nuts will certainly dispute this). So if you use an external microphone with this microphone (it has a connector for that), you could get quality audio out of it. BUT, it you use the build-in microphone elements... They use 2 plain electret pressure capsules side by side in a block of foam! Similar to the 50cent Radio-Shack special. Channel separation is about nil, and the overall quality is marginally better than a telephone. It is really a very odd device: state of the art electronics with sub-consumer grade acoustics. -- -- Andreas Nowatzyk (DC5ZV) Carnegie-Mellon University agn@unh.cs.cmu.edu Computer Science Department (412) 268-3617
iws@rayssdb.ray.com (Ihor W. Slabicky) (01/11/90)
In article <7471@pt.cs.cmu.edu>, agn@unh.cs.cmu.edu (Andreas Nowatzyk) writes: > Some time ago, I had a chance to play with it, but the unit in question > may have been a prototype or an alpha version, so take the following > comments with a grain of salt. > > Electronically, the unit is indeed cute. It is a bit warm because it > consumes a bit more power than you'd like. The LED's are fine and the > fidelity from electrical signal in to digital out is probably ok > (golden ear audio nuts will certainly dispute this). > > So if you use an external microphone with this microphone (it has a > connector for that), you could get quality audio out of it. > > BUT, it you use the build-in microphone elements... They use 2 plain > electret pressure capsules side by side in a block of foam! Similar to the > 50cent Radio-Shack special. Channel separation is about nil, and the > overall quality is marginally better than a telephone. It is really a very > odd device: state of the art electronics with sub-consumer grade acoustics. ... excerpted from TV Technology, November 1989 issue ... Ariel Introduces Digital Microphone The new mic, by Ariel Corp., utilizes two powerful new Motorola a-to-d chips to sample and convert stereo analog signals to digital info. A high quality broadcasting/recording version of the mic with an AES/EBU standard output will be shown at the October AES convention in NYCity. A special version of the Ariel Digital Microphone, which can only be used with the NeXT Computer System is on sale now for $595. The Model DM-N has two electret condenser capsules in an x/y configuration to pick up analog sounds in stereo. Two 56ADC chips convert the analog signals to digital format. The device has a dynamic range of up to 92 dB with a total harmonic distortion of 0.005 percent. The digital mic allows the user to limit the bandwidth of the acquired signals. The NEXT computer, through software selection can adjust the mic's sampling rate to one of five values from 88.2 KHz down to 5.5 KHz, including the digital audio standard of 44.1KHz. The mic also has line level R and L input jacks for directly connecting outboard equipment through it's A-to-D conversion circuitry. Devices range from compact discs and DAT players can be connected to the mic. For broadcast and recording studios, Ariel has plans for digital signal processing that can include computer manipulation of the mic's characteristics, digital low cut filters, automatic squelching of feedback, and auto mic mixing. No signal processing occurs inside the mic. The A-to-D conversion has been as close as possible to the source to eliminate interference, hums, and buzzes. When asked to compare the sound of the Ariel Digital Microphone to the top-of-the-line precision studio mics from Neumann and Schoeps, Ariel begged off, saying no head-to-head comparisons have been made. (A b/w photo shows the NeXT mic next to the NeXT mouse - the mic is about twice as long as the mouse and only 2/3 as wide.) For information from Ariel Marketing, contact Les Listwa at 201-249-2900.
jtkung@mit-caf.MIT.EDU (Joseph Kung) (01/11/90)
In article <4390@rayssdb.ray.com> iws@rayssdb.ray.com (Ihor W. Slabicky) writes: > >When asked to compare the sound of the Ariel Digital Microphone to the >top-of-the-line precision studio mics from Neumann and Schoeps, Ariel >begged off, saying no head-to-head comparisons have been made. > I was wondering how Ariel implements the anti-aliasing filters needed BEFORE A/D conversion. If it doesn't, then I don't see the point of sampling at 44.1 kHz. I thought that all high-end digital recorders utilize steep anti-aliasing filters before conversion, and this is one of the reasons why digitally recorded stuff can suffer from phase distortion, etc. Oversampling would be nice, but they don't make 16 bit, 176.4 kHz (4X) A/D converters unless you want to pay an arm and a leg. - Joe -- Microsystems +---------------------------------+ 77 Massachusetts Avenue Technology | Joseph Kung, jtkung@caf.mit.edu | Room 39-627 Laboratories, MIT +---------------------------------+ Cambridge, MA 02139
hc@arp.anu.oz.au (Hugh Clapin) (01/12/90)
From article <4390@rayssdb.ray.com>, by iws@rayssdb.ray.com (Ihor W. Slabicky): > In article <7471@pt.cs.cmu.edu>, agn@unh.cs.cmu.edu (Andreas Nowatzyk) writes: > >> BUT, it you use the build-in microphone elements... They use 2 plain >> electret pressure capsules side by side in a block of foam! Similar to the >> 50cent Radio-Shack special. Channel separation is about nil, and the >> overall quality is marginally better than a telephone. It is really a very >> odd device: state of the art electronics with sub-consumer grade acoustics. > > > ... excerpted from TV Technology, November 1989 issue ... > > A special version of the Ariel Digital Microphone, which can only > be used with the NeXT Computer System is on sale now for $595. > The Model DM-N has two electret condenser capsules in an x/y > configuration to pick up analog sounds in stereo. Two 56ADC chips > convert the analog signals to digital format. The device has a > dynamic range of up to 92 dB with a total harmonic distortion of > 0.005 percent. Just a note of clarification (I know nothing about this device other than what's been posted here) - the `device' in question in the press release could *only* refer to the d-a, not to the whole system, capsule and all. If the actual microphone capsules are anything like as bad as is indicated by the first poster, then THD would be far above 0.005% . I have no figures but I would guess a Radio Shack cheapy mic would have a THD in the order of 0.5-1% . The idea of *good* mic with a built in d-a is interesting, however probably unnecessary for most professional (and I would think computer/sampling) applications. Mic level signal in any decent mic is balanced, and thus rejection of noise, hum etc is pretty good. The advantage of doing your d-a at mic level may be justified in some areas, but such devices already exist as outboard units. The acoustics and electronics of building a good microphone are probably much harder than accurate d-a and a-d. For most professional applications you'd prefer to be sure of your microphone, and risk the extra (tiny) amount of noise in a pre-amp than put up with a sub-standard mic. I could see that it might be convenient for computer sampling applications where broadcast/recording standards are not important. hugh clapin
bergman@m2c.m2c.org (Michael Bergman) (01/13/90)
For something really new, someone (I think a university in Ca, but am not sure; sorry) has recently developed a chip with a "micromachined" microphone ON THE CHIP (cmos) along with the preamp. 200 Kiloherz range... the article said something about use as a ultrasonic pickup. If I find it again, I'll type in some more details. As far as the article went, there are no audio uses planned for this particular chip, but Hey! the technology's here.... -- --mike bergman Massachusetts Microelectronics Center 75 North Drive, Westborough, MA 01581, USA +1 (508) 870-0312 UUCP: (...harvard)!m2c!bergman INTERNET: bergman@m2c.org