Taperssection.com
Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: sunjan on April 06, 2009, 04:00:07 PM
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Hey all,
Just discovered these:
http://www.atiaudio.com/?fa=products&category=28#
Looks like poor man's alternative to a Mixpre, but these suckers retail for over $800! ::)
Anyone heard about them?
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The first introduction to ATI was with the ATI Paragon series II console and let me tell you these guys make great products simply one of the best preamps I have ever used. So I would say these guys are good choice.
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My initial reaction to that info on that link is that most of the phantom voltages fall well below the 48 that many of "our" mics require. I turned away...
When you measure most of these types of devices you would be surprised how much real world voltage drop is present in most of them... The other companies just dont advertise it :)
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Probably right, I'm just used to believing what I read. They do look like solid products...
I think that Chris meant that the phantom voltage on some of the 48V phantom devices out there will droop pretty far when put under load, farther than you'd expect from simply drawing from 48 V through the usual 6.81 kohm resistor pair. Basically, what you should have is a solid 48 V supply that feeds the signal+ side through a 6.81k resistor and feeds the signal- side through another 6.81k resistor. The maximum amount of current that can be pulled per mic is 10 mA, so a maximum of 5 mA will flow in each resistor. When 5 mA flows in a 6.81k resistor, it drops 34.05 V, so the voltage supply directly to the mics is a minimum of 13.95 V. What Chris is saying is that some of those 48 V phantom supplies can't supply 10 mA without sagging, so the result is that you don't actually get 13.95 V at the mic. You get something less than that. The point is that you don't get as much voltage at the mic as it was designed to use if the 48 V supply itself starts to sag under load. (Please note that you can't just measure the voltage at the mic to tell if the 48 V phantom supply is sagging. You also need to know what DC current is drawn by the mic. So, just because your own mic shows more than 13.95 V on it does not mean that the 48 V supply is not sagging. It might be because your mic draws less current, so less voltage is dropped across the 6.81k resistors. In fact most mics draw considerably less than 10 mA. There are very few that actually push that 10 mA limit. I'm told that some models of Earthworks mics draw a lot of current and come close to that limit.
I should also point out that the phantom voltage spec does also include a variant that runs at 24 V, but with smaller bias resistors to make up for the lower supply voltage. I'll bet that the ATI preamps conform to that variant of the spec.
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This company is NOT the same one that Chris is referring to. The "real" (for lack of a better word) ATI is Audio Toys, Inc., parent company of API. They are now known as API (the ATI name and brand has been absorbed).
http://www.audiotoys.com/
These other guys look like they're capitalizing a little on name brand recognition (or confusion, maybe).
If this thing had Paragon-level preamps in it, I'd pay $800 for it in about half a second.
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Good catch, TNJazz. :coolguy:
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This company is NOT the same one that Chris is referring to. The "real" (for lack of a better word) ATI is Audio Toys, Inc., parent company of API. They are now known as API (the ATI name and brand has been absorbed).
http://www.audiotoys.com/
These other guys look like they're capitalizing a little on name brand recognition (or confusion, maybe).
If this thing had Paragon-level preamps in it, I'd pay $800 for it in about half a second.
I thought ATI was still around just making preamps now because the large console business dried up after companies started making digital consoles that could tour.. Thanks for the correction funny thing is the VU meters look exactly like a paragon console. I was tricked!
Chris
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I thought ATI was still around just making preamps now because the large console business dried up after companies started making digital consoles that could tour.. Thanks for the correction funny thing is the VU meters look exactly like a paragon console. I was tricked!
Chris
ATI is still around, sort of. It's now a part of API but they still make the 8mx2 as an ATI branded product. You can buy it from API but it still carries the ATI logo.
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This company is NOT the same one that Chris is referring to. The "real" (for lack of a better word) ATI is Audio Toys, Inc., parent company of API. They are now known as API (the ATI name and brand has been absorbed).
http://www.audiotoys.com/
These other guys look like they're capitalizing a little on name brand recognition (or confusion, maybe).
If this thing had Paragon-level preamps in it, I'd pay $800 for it in about half a second.
Actually Audio Toys inc. After I did some checking have not been around for quite as long as ATI they have been in business for 30 years. Audio Toys Inc. Started calling them selves ATI for short. The real ATI told them to stop and they complied for the most part. They actually had to take down the name on the building.
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This company is NOT the same one that Chris is referring to. The "real" (for lack of a better word) ATI is Audio Toys, Inc., parent company of API. They are now known as API (the ATI name and brand has been absorbed).
http://www.audiotoys.com/
These other guys look like they're capitalizing a little on name brand recognition (or confusion, maybe).
If this thing had Paragon-level preamps in it, I'd pay $800 for it in about half a second.
Actually Audio Toys inc. After I did some checking have not been around for quite as long as ATI they have been in business for 30 years. Audio Toys Inc. Started calling them selves ATI for short. The real ATI told them to stop and they complied for the most part. They actually had to take down the name on the building.
interesting!
I wonder if that's why API absorbed ATI instead of the other way around?
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I have to agree with SparkE! that the implementation of phantom powering in most portable, (relatively) low-cost recording equipment is substandard. That affects different microphones differently, but is definitely something that equipment reviewers ought to test and report on, in my opinion. People may assume that they're giving a microphone a good honest try while in fact they may be "testing" the power supply that it's operating from.
As for 24-Volt phantom powering, section 7.4.5 of the current DIN/EN/IEC standard for phantom powering still not only describes it, but says (translating from the German): "While 12-V and 48-V arrangements are still in use, 24-Volt arrangements are recommended for new developments." Meanwhile the official German version of this standard has a "national remark" attached as a footnote: "The 24-Volt supply arrangement did not become a practical success. Proposals for an amendment [to section 7.4.5] are under advisement."
I know of only one manufacturer that ever made a microphone publicly available specifically for standard 24-Volt phantom powering--and it accepted standard 48-Volt phantom powering as an alternative! Apart from certain "packaged systems" (such as P.A. systems for fixed installation in churches and meeting halls) I know of no mixer, recorder or preamp that has ever offered it, either.
If reliable, miniature DC/DC converters been available in the 1960s when phantom powering was first adapted for powering microphones (before that, it was a system for powering telephone equipment), then 24 Volts would have been a very sensible choice, and a lot of trouble might have been spared. But that's just not how things went--the proposal for 24-Volt phantom powering simply came too late, after the 12- and 48-Volt methods had already been well established.
The issue of equipment compatibility is serious, especially since the standard value of 1.2 kOhm for the resistors is too low for some existing P12 microphones--they can be damaged if they're connected to a P24 socket. Just because a spec sheet says "9-52 Volts" doesn't mean that a microphone can handle the maximum supply current for any voltage in that range!
--best regards
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mshilarious, with all the battery-powered recording we all do, I'm surprised that there's not more enthusiasm here for 12-Volt phantom powering. DC/DC converters tend to be less efficient when they're only making a minor step upward in voltage, such as 42 Volts -> 60 Volts; they can be considerably more efficient when it's like 10 Volts -> 60 Volts.
As an example, take the two modes that the Schoeps CMC 6 has:
P12 mode, 8 mA = 12 x 8 = 96 mW
P48 mode, 4 mA = 48 x 4 = 192 mW
... for identical performance either way. That's a 2:1 difference in power consumption, but then there's the fact that DC-operated 48-Volt phantom power supplies themselves are usually a lot less efficient than corresponding 12-Volt supplies. They mostly have DC converters in them, so even more power is being wasted generating 48 Volts just so that it can get knocked down to some lower voltage just so that it can be stepped up to a higher voltage again.
48 Volts is not a wonderful standard. The only really good thing about it is that a standard exists.
--best regards