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Which A/D converter for classical?

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Old 19th April 2008   #121
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Triple linear PSU

Mouser # 597-TAA-16W , 16W triple linear PSU , +- 15V & +5V
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597-TAA-16W
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Old 19th April 2008   #122
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Within two weeks I will get here Danish DIgital Audio AX-24 AD DA to try. In the meantime I got Fred Forssell´s custom made AD (which was found sounding yet better than Lavry Gold in some tests - for example http://www.gearslutz.com/board/1918554-post22.html and http://www.gearslutz.com/board/1918606-post25.html)

I was quite blown away by it ... comparing to it, my Lavry Blue sounds a bit muffled, less detailed and less 3D. It opened a new era in my recordings. (but it is not a commercial product, just an experiment)

I disagree a bit with some opinions here that AD convertor has a relatively small role in the recording chain. To my experience, it has quite a big role, more or less the same important as the preamp - and the overall sound differences between various quality levels of convertors can be night and day . If you have great mics and preamp and mediocre convertor, the sound result may be also close to mediocre - because of the poor conversion of the original sound to the digital domain.

Now I am going to try these DAD converters, since people have very high opinion about them and if they sound reasonably better than Lavry Blue, I may replace it. I will write some report soon ...
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Old 23rd April 2008   #123
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Mouser # 597-TAA-16W , 16W triple linear PSU , +- 15V & +5V
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597-TAA-16W
would I still need the torroidal tranformer if I buy this prebuilt powersupply?
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Old 25th April 2008   #124
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Questions for Jim Williams concerning the PCM4222EVM :

1. will this work with any preamps
2. is the power supply you are refering to the Power One HTAA-16w-AG


thanks for the suggestion
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Old 25th April 2008   #125
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Cool

Quote:
Originally Posted by Stefanizzi View Post
I need a very clear and uncoloured 2 channel AD converter. I don't need sampling frequencies over 96kHz.
My budget is restricted to $ 4,500.
I use the Audio Design DMA2.



It should retail in the US for around £1,000 I would guess (It's under £600 in the UK).

It's almost as good as a Prism at a fraction of the price. It's clean, neutral and, as level adjustment is by click-stops, it's repeatable.

It's so good, I am thinking of getting a second one.
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Old 25th April 2008   #126
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Quote:
Originally Posted by aracu View Post
Questions for Jim Williams concerning the PCM4222EVM :

1. will this work with any preamps
2. is the power supply you are refering to the Power One HTAA-16w-AG
thanks for the suggestion
It will work with any preamp. I made my own power supply using Linear Tech LT1085 regulators, they are very good. Any + and - 15 volt supply will work as long as an additional 5 volt supply for the logic is provided. I split the 5 volt supply feeds so there are 3 x 5 volt regulators and 3 different 5 volt feeds.

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Old 25th April 2008   #127
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Jim thanks for your kind advice. Don't mean to frustrate you, but I might
connect it wrong without a simple diagram to follow. If there is one that
you or anyone else could refer me to I would greatly appreciate it.

The specs of the Power One HTAA-16W-AG PSU (going for $75. ) :

18 watts, triple output linear psu w/ 5, +15, -15, the 5 is isolated and
can be used as + or - polarities, max. amps: 2, 0.4 and 0.4,
vin range: 87-264, Voltage, output:5V dc, Voltage, supply:230V,
Current, output:2A, Current, output 2:0.4A, Current, output 3:0.4A ,
RoHS Compliant: Yes

In case anyone spots an incompatability... thanks.
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Old 25th April 2008   #128
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That PSU will work, but if you want to save 10 bucks, go with the equivalent model made by Condor, it's $65.49.
Part # HTAA-16W-A+G, Digi Key # 271-2289

Connections are easy, the wall AC cable typically connects from pin's 1 + 4. I usually tie the chassis to the AC ground wire via a washer/terminal and a 4-40 screw and 4-40 keps nut. There is a wiring chart with each unit. It shows how to connect to any voltage in the world via jumpers, but is set default to 120 v AC.
The +5 volt output connects to the + 5 volt screw terminal on the eval pcb, the 0 or common pin connects to the ground screw terminal. On the opposite side of the eval pcb, connectr +15 v to +15 v screw, connect -15 v to the -15v screw and the common or 0 to the ground or 0 in screw. Easy.

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Old 26th April 2008   #129
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Thanks, very much appreciated!! It's heartwarming that you share your ideas
and knowledge, which can potentially improve a studio at a very low cost. My experience with power supplies is limited to replacing computer psu's. I'm curious to compare these converters to the built in Sound Devices (recorder) converters, which I quite like. I've never invested in expensive stand alone converters, having heard that the technology moves ahead quickly.
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Old 26th April 2008   #130
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Originally Posted by ISedlacek View Post
Within two weeks I will get here Danish DIgital Audio AX-24 AD DA to try.
...
Now I am going to try these DAD converters, since people have very high opinion about them and if they sound reasonably better than Lavry Blue, I may replace it.
Which configuration are you getting? The mic preamp version?

(I'm actually more interested in their mic preamp architecture than their AD converter technology.)
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Old 26th April 2008   #131
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Quote:
Originally Posted by Jason West View Post
Which configuration are you getting? The mic preamp version?

(I'm actually more interested in their mic preamp architecture than their AD converter technology.)
I am not interested in preamps at all. Just to try AD DA conversion (AX-24) and to see how it comes comparing to Lavry Blue/Black and Forssell AD
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Old 26th April 2008   #132
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Quote:
Originally Posted by Jason West View Post
(I'm actually more interested in their mic preamp architecture than their AD converter technology.)
AX24 strenght lies in conversion, not in mic preamps.

Regards
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Old 26th April 2008   #133
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AX24 strenght lies in conversion, not in mic preamps.
I'll agree that on the surface level, the converter technology is what gets everyone's attention.

However, they are also implementing an unconventional mic preamp architecture that seems similar to StageTec TrueMatch RMC (and also possibly Neumann Solution D). They are doing the A/D at mic level instead of line level; this avoids unnecessary gain.

This approach could have much more influence on quality of sound than the latest/greatest converter chip. I'm intrigued that the DAD AX24 might exceed sound quality of a Gordon Model 5 + Lavry Gold because of the optimized gain structure. The Gordon website says that the #1 cause of distortion in mic preamp is gain. If everyone agrees with this, then it seems reasonable to avoid amplifiying the signal to line-level for A/D if you're recording straight into the computer.

I do a lot of acoustic recordings digital-direct-to-disk. No outboard gear used at all. I really can't think of a good reason why I need to boost my mic signal to line-level. Can anyone give a good reason?

Here's my thinking: If there's no outboard gear such as compressor/eq are needed in the signal path, then why bother with adding 18dbu+ of gain just for A/D conversion?! If huge gain is actually "desirable" for A/D conversion, then why not continue that logic and amplifiy mic-level signals to speaker-level and create A/D converters that work with hotter speaker-level signals?

Anyways, how did you determine if AX24 improvement in sound is caused more by the converter vs the mic preamp gain stage architecture? Did you have a chance to evaluate it? I asked TransAudio about getting one but there are none in the USA for demo. I'd have to pay $12,000 with no return policy. [EDIT: I just saw your post #32 that said you tried the AX24 mic preamp in Vienna.]

So, as unusual as it may seem, I'm not all that interested in the DAD AX24 for the DSD or DXD converter. I'm much more curious about its mic preamp---or more precisely, I'm more curious about its optimized mic preamp gain structure going into the AD.
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Old 26th April 2008   #134
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Originally Posted by ISedlacek View Post
I am not interested in preamps at all. Just to try AD DA conversion (AX-24) and to see how it comes comparing to Lavry Blue/Black and Forssell AD
If you happen to be getting an AX24 with mic preamp modules, it might be worth your while to check it out.

I think it has a chance to exceed the Gordon Model 5 + Lavry Gold and Forssell SMP-2 + Forssell prototype AD for the reasons I stated to Stefanizzi.

I'm surprised that you wouldn't want to investigate the mic preamp modules since the gain architecture seems to be optimized for your type of acoustic recording projects.
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Old 26th April 2008   #135
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Quote:
Originally Posted by Jason West View Post
I'm surprised that you wouldn't want to investigate the mic preamp modules since the gain architecture seems to be optimized for your type of acoustic recording projects.
Life is too short. Music is what counts ... Some of my recordings people love the most were made 12 years ago in the local radio studio on a setup that would horrify me today ... Yet it is loved by listeners ...

Today I have amazing setup (based on long term refining), that I am happy with and now I will rather concentrate on improving my music than further trying and exploring similar types of machines ... Top notch DA is the last thing I can think about ...
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Old 26th April 2008   #136
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Quote:
Originally Posted by Jason West View Post
This approach could have much more influence on quality of sound than the latest/greatest converter chip. I'm intrigued that the DAD AX24 might exceed sound quality of a Gordon Model 5 + Lavry Gold because of the optimized gain structure. The Gordon website says that the #1 cause of distortion in mic preamp is gain. If everyone agrees with this, then it seems reasonable to avoid amplifiying the signal to line-level for A/D if you're recording straight into the computer.
I do a lot of acoustic recordings digital-direct-to-disk. No outboard gear used at all. I really can't think of a good reason why I need to boost my mic signal to line-level. Can anyone give a good reason?
Maybe, maybe not. Quality mic preamps can obtain THD levels well below that of the internal mic's circuitry. Some measure very low distortion even at higher gains, below .001%, some measure as low as .0002% IMD at + 40 db of gain. I know of no commercial condenser mic with distortion that low. The problem of a mic preamp's THD that is an order of magnatude below that of the microphone is really not a problem.

Also consider dynamic range. Modern A/D converters are optimized for line level inputs, that allows the entire 120 db dynamic range to be used. Take gain, analog or digital and that dynamic range is reduced, an important consideration with acoustic or classical music. No converter topology will reduce the distortion presented by the microphone. Clean up the mics and then you might be getting somewhere.

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Old 26th April 2008   #137
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Quote:
Originally Posted by Jason West View Post
If you happen to be getting an AX24 with mic preamp modules, it might be worth your while to check it out.

I think it has a chance to exceed the Gordon Model 5 + Lavry Gold and Forssell SMP-2 + Forssell prototype AD for the reasons I stated to Stefanizzi.

I'm surprised that you wouldn't want to investigate the mic preamp modules since the gain architecture seems to be optimized for your type of acoustic recording projects.
You said WHAT????
What HO??

Why do you say this?-----Specifically you say, "I think it has a chance to exceed. . ."
Is this hearsay or did you do the comparison?

You are going against the Bible here, I hope you know.

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Old 26th April 2008   #138
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Maybe, maybe not. Quality mic preamps can obtain THD levels well below that of the internal mic's circuitry. Some measure very low distortion even at higher gains, below .001%, some measure as low as .0002% IMD at + 40 db of gain. I know of no commercial condenser mic with distortion that low. The problem of a mic preamp's THD that is an order of magnatude below that of the microphone is really not a problem.
Maybe I'm (or we?) are reading too much into the quote I was referring to. The quote from Gordon homepage is "The primary source of distortion in any preamplifier is gain."

Honestly, I don't know if Grant Carpenter was using the word "distortion" specifically for THD or just used the word casually to describe "any unwanted artifacts" (e.g. noise, transients, THD, etc.)

So while you're probably right about the THD, there may be other audio anomalies that would benefit from the alternative mic-level A/D approach.

Quote:
Also consider dynamic range. Modern A/D converters are optimized for line level inputs
But that's exactly where I'm wondering if this is the right approach. Are A/D converters optimized for line-level inputs by tradition (because decades of audio equipment run at -10/+4 line levels). Or is it because some research has been done to compare A/D conversion done at mic-level vs line-level vs speaker-level and the unanimous result was that line-level was the absolute highest fidelity.

In other words, if there were no constraints for A/D design to interface with existing gear (e.g. outboard tube compressors), would we still arrive at using line-level signals? If line-level is the holy grail, then what is the merit to A/D at the mic-level as done by StageTec TrueMatch, Neumann Solution D, and AX24?

I'm definitely not dismissing traditional mic preamps at all. To record vocals I would do something like this:
Neumann M149 --> Gordon Model 5 --> Tube-Tech CL-1B --> Lavry Gold A/D at line-level
But if I were recording acoustic guitar direct-to-disk, I would do something like this:
Schoeps MK2 --> DAD AX24 A/D at mic-level
So given the acoustic guitar scenario, is there a compelling reason to boost to line-level? Especially if there are AD converters (Stagetec, DAD) that don't need line-level? If I just want the vibrations of the string to go straight to digital as zeros and ones, what does boosting it by 18+dbu line-level buy me? This is what I'm unclear about.

Appreciate your thoughts on this.
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Old 26th April 2008   #139
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Why do you say this?-----Specifically you say, "I think it has a chance to exceed. . ."
Is this hearsay or did you do the comparison?
I did not do a comparison. I was only presenting a discussion point regarding an alternative mic gain structure.


Quote:
You are going against the Bible here, I hope you know.
Maybe going against the Bible for general recording (rock, pop). But maybe not when it comes to the approach that's used for transparent classical recordings.

Many classical (and some acoustic jazz) recordings boast of going from microphone direct to disk with no eq or signal processing of any kind. If this purist philosophy is pursued to the fullest extent, then it seems reasonable to examine exactly why we boost mic-level signals to line-level. This is what I'm unsure about.

Also to be clear, I'm not trying to say brand name X is better than brand name Y.
I'm not saying that AX24 is better than Lavry Gold.
I'm trying to get everyone's viewpoint on whether mic-level A/D is better than line-level A/D.
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Old 26th April 2008   #140
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You said WHAT????
What HO??

Why do you say this?-----Specifically you say, "I think it has a chance to exceed. . ."
Is this hearsay or did you do the comparison?

You are going against the Bible here, I hope you know.

Boo-ya-ka-sha!
I spoke to the designer at length about the design in Germany and I would agree that it shows interesting potential for optimal performance.

DAD kindly allowed me to use their DA section for the audio demos in one of my presentations and it was very impressive.

I also recall it being a fair bit brighter than the 192s that were also available but this was most likely due to interactions between the speakers & the differences in output electronics.

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Old 26th April 2008   #141
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Hey Andy, that is a fantastic quartet recording, with great music. If it's not too much of a digression, tell us about your mics and how you went about making the recording (haven't heard the other mp3s yet).
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Old 26th April 2008   #142
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The reason that a/d uses line inputs is that traditionally the output of the mic amp or console was a +4 line output. There were no a/d converters built into the microphone.
That's the historical part.

Fifteen years ago or so mic manufacturers attached an a/d to the mic output electronics and called it a digital mic. It wasn't really a digital mic though---it was a mic with the a/d attached.

Now Neumann and others have put a miniature a/d right behind the output of a mic capsule. It is their own design and other designs (Stage-Tec gain ranging design) imitate it with or without it's technical merits.

There are benefits and drawbacks of the Neumann design. There are limited clocking options for largee scale deployments of these so-called digital mics, or even for small stereo pair recordings. Options will proliferate in the future, but these mics are in very limited usage. This argues for keeping the input to the a/d line level.

Measurement in the laboratory also makes a pretty good solid argument for maintaining the input to be line level. Performance is measured to be stunningly good.

I would argue that it is convenience items and convenience preferences which exert some market pressure to make a move to the so-called digital mic. Large state broadcasters and facility people who can pay find the in line compressors, limiters, tone color wheels and remote control to be attractive. The color brochure from the manufacturer hopefully seals the deal to the Asian state broadcast organization or Olympic broadcast facilities.

Comparing these new and not time tested digital output mics to "best of class" analog set-ups is totally legitimate---if you actually do any comparison. Guessing and fantasizing won't make it though.

The fact is that many of these digital mics are attached to rejected capsule designs. The sound the microphone makes is rejected out of hand. Thus they are thin on the ground and not seen. They are still an experiment. Besides I have yet to see a fine tube mic paired with an on board a/d treatment. Yet this is easily accomplished in the studio or hall. I'm thinking of my current fave signal chain which is a FLEA 49 into a
Thermionic Culture Earlybird into a dCS 905 converter. Eat my shorts digital mic proponents.

Allusions to direct to disc recording (an interesting technique whose audiophile wow factor crested 30 years ago) are suspect. These direct to disc recordings captured some of the most constipated playing ever recorded. Don't bring audiophile gobbledegook in to this room!

Perhaps the actual problem is that the people fantasizing about an ultimate sound have not yet heard that sound with traditional set-ups available today.
Certainly neither noise nor lack of dynamic range is a problem in these traditional set-ups. Yet these supposed "problems" are the exact ones that the digital mic set-up or digital no mic amp set-up attempts to solve.
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Old 26th April 2008   #143
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Fifteen years ago or so mic manufacturers attached an a/d to the mic output electronics and called it a digital mic.
I've got one - Beyer MCD 100... Very nice mic, e.g. as a spot mic for a soprano. Despite the possibly outdated converter and SRC technology, I'm considering getting two more...

Quote:
There are benefits and drawbacks of the Neumann design. There are limited clocking options for largee scale deployments of these so-called digital mics, or even for small stereo pair recordings.
Could you be more specific? Where are these limitations?

Quote:
Allusions to direct to disc recording (an interesting technique whose audiophile wow factor crested 30 years ago) are suspect. These direct to disc recordings captured some of the most constipated playing ever recorded. Don't bring audiophile gobbledegook in to this room!
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Old 26th April 2008   #144
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Fifteen years ago or so mic manufacturers attached an a/d to the mic output electronics and called it a digital mic. It wasn't really a digital mic though---it was a mic with the a/d attached.

Now Neumann and others have put a miniature a/d right behind the output of a mic capsule. It is their own design and other designs (Stage-Tec gain ranging design) imitate it with or without it's technical merits.

There are benefits and drawbacks of the Neumann design.
I only wanted to mention Neumann Solution D as just one example of the A/D at mic-level architecture. I'm not really wanting to debate digital mics and its associated AES42 protocol, etc.

The real interesting question to me is the A/D being done at mic-level. Now whether that A/D chip is embedded inside the mic body (e.g. Neumann Solution D) or it sits inside a 2U rack mount chassis (e.g. DAD AX24 or StageTec TrueMatch) is academic (to me) and isn't relevant for discussing the technical merits of converting a mic-level signal.

You're sending this discussion on a tangent about "digital mics" that I didn't intend. Although it could also be said that my questions about mic-level are diverging away from Stefanizzi's original question. I'll create a new thread about this mic-level vs line-level topic.

Quote:
Originally Posted by Plush View Post
Allusions to direct to disc recording (an interesting technique whose audiophile wow factor crested 30 years ago) are suspect. These direct to disc recordings captured some of the most constipated playing ever recorded. Don't bring audiophile gobbledegook in to this room!
I don't understand what you're trying to say here. When I sit down to record an acoustic guitar session, my natural state of mind is to just record the DPA/Schoeps mics straight to disc. I'm not doing a top-40 power ballad, so I don't need chorus or delay. The bass+treble of the guitar is balanced enough for my ears so I don't need to insert EQ into the chain. I just don't have a need to insert any of these signal processors that require a line-level signal. I've never thought of this approach as exotic or "audiophile". It's just seems to be a natural straightforward way to record a simple instrument. Did you say that if I "invent" a reason to insert an EQ into my signal chain, then the unpure recording path will now relieve constipation? .... Did I misinterpret what you said?

So, if I don't need line-level signal, then why would I want to boost the mic-level another 18dbu to make it line-level? Hmmm... I make it line-level so I can use a line-level A/D converter like Lavry/Weiss/dcs?! Seems like an interesting circular argument. So, let's change the rules a bit: what if we use A/D converters that work at mic-level (e.g. the 2 rackmount units from DAD and StageTec that do this). In this situation, what's the remaining motivation for boosting to line-level?

What if Dan Lavry came out with 2 different A/D converter models: one that worked at line-level and another that worked at mic-level. Would the mic-level version be better in any situation? Would it sound worse? Why?

Maybe it's best to convert my Schoeps MK2 mic-level signal directly in to digital zeros/ones.
Maybe it's best to convert my Shure SM57 into digitial bits at mic-level.
The Neumann Solution D mic need not be part of this discussion at all. (I'm not interested in Neumann's mic.)

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Measurement in the laboratory also makes a pretty good solid argument for maintaining the input to be line level. Performance is measured to be stunningly good.
I'll address this point in another thread.
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Old 27th April 2008   #145
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Greetings Jason West,

Your good postings ask excellent questions and you obviously are informed about recent developments in a/d work.

The reason I gave the background on the Neumann Solution D range is that they have a good system which fulfills your requests. I cannot agree that miniature a/d converters powered by a dc converter are competitive with ac powered racked a/d converters. Perhaps this is a separate discussion.

The Neumann system, the StageTec system and all others just amplify the mic signal digitally. The reason they exist is that they claim to expand useable dynamic range and avoid loss of detail. It's true that they are converting the signal to digital at a different point than traditional mics plugged into a mic amp and then an a/d converter.

By the way, I took your term--"direct to disc recording" to mean direct to a lacquer that makes an LP.

I think we are in agreement that these new developments are worth checking out. I would be interested to use the DAD box. I have tried the Neumann "solution" and the results were clinical and laboratory clean. Not my bag.

It's just that the results must be worlds ahead to justify making a move. These systems have been out for a while, allied to poor sounding mics and have flopped in the marketplace. It seems having everything inside a black box has not met with the favor of tonmeisters.

I suppose the question I must ask is what problems are you wanting to solve with your current set-up?
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Old 27th April 2008   #146
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The reason I gave the background on the Neumann Solution D range is that they have a good system which fulfills your requests. I cannot agree that miniature a/d converters powered by a dc converter are competitive with ac powered racked a/d converters.
Good points. I'm not interested in the Neumann Solution D capsules---but I am interested in the mic gain architecture. This is why the DAD AX24 and Stagetec TrueMatch really intrigues me... I seem them as a gateway to the "mic-level A/D" technology for non-Neumann mics (DPA, Shure, AKG, etc). The DAD/Stagetec rack gear lets me avoid the penalty of Neumann "reject capsules".

Could mic-level AD offer more realism, more detail, more emotional intangibles? I don't know---I've never tried it yet---but I'm very curious to find out. It sounds promising on paper.

It is unfortunate that the Neumann Solution D was not well received. In my opinion, that product may taint the discussion of mic-level AD for a long time. If the Neumann sounds bad, it may be the capsules, or bad AD chip, or bad digital amplifcation algorithms that are to blame. The mic-level AD may have nothing to do with the "bad sound" but unfortunately will get lumped in with the other real reasons and will be difficult to isolate in a debate.

However, your comments indicate that you've isolated the mic-level AD portion of my questions and you're open-minded to its possible merits.


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Originally Posted by Plush View Post
The Neumann system, the StageTec system and all others just amplify the mic signal digitally.
Yes, and this is the function I don't need. I want to record directly to computer so the "line-level outputs synthesized by digital amplification" is irrelevant to my needs.

Quote:
Originally Posted by Plush View Post
It's true that they are converting the signal to digital at a different point than traditional mics plugged into a mic amp and then an a/d converter.
Yes, this is the core idea that has me wondering about improved quality. Also, this gain architecture seems to be off the radar of many folks. Hardly any discussion about this aspect at all.

Quote:
Originally Posted by Plush View Post
By the way, I took your term--"direct to disc recording" to mean direct to a lacquer that makes an LP.
As I already guessed--a misunderstanding. A few weeks ago, I told a 20-something year-old kid, "there's no point for you to repeat it--you sound like a broken record". He didn't know what a "record" was. I need to upgrade both my cliches and my mic preamps!

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Originally Posted by Plush View Post
I suppose the question I must ask is what problems are you wanting to solve with your current set-up?
I can't say I have any obvious audio fidelity "problems" at the moment. But I won't rule out that I can get better quality recordings than what I'm doing now. I'm interested in the DAD AX24 but I'm hesitant to spend $12k for something I can't return. Its unconventional mic preamp architecture has had zero discussions so far.

But I'm thinking that maybe DAD,Stagetec are ahead of the game and this mic-level AD approach is possibly the start of a trend. Both Neumann and Schoeps have mic-level AD. (I deliberately avoided the term "digital mic" -- too many negative connotations -- instead I say Neumann/Schoeps offer mic-level AD.) So that's 4 companies right there. d_fu mentioned beyerdynamic. So i guess that's at least 5. Maybe in 10 years, there will be 10 more companies offering this mic-level AD technology. And TI/BurrBrown/Crystal will have AD chips that work natively at mic-level with no opamps required.

Now a skeptical person could say there is absolutely no audio merit for mic-level AD. And that it is only pursued as a convenience mechanism for AES42 protocol to control the mic digitally (adjust the polar pattern remotely, etc.) That could have been a possibility but the DAD AX24 does not offer AES42 remote control. Therefore it seems they had a pure audio-quality motivation for implementing mic-level AD.
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Old 27th April 2008   #147
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Quote:
Originally Posted by Plush
The Neumann system, the StageTec system and all others just amplify the mic signal digitally.
Then Jason West replied:
Yes, and this is the function I don't need. I want to record directly to computer so the "line-level outputs synthesized by digital amplification" is irrelevant to my needs.
===================================================

Now hold on a second, bro. Of course you need it--otherwise you won't hear anything.

All the DAD or StageTec design does is substitute digital mic pre amplification instead of analog mic pre amplification. If you believe that the signal benefits strictly from conversion to digital earlier than in the traditional stage, then this set-up may be for you. I don't understand what problem it is solving.

Unless you have a problem that needs to be solved, then there is no indication to change your set-up. (other than curiosity and bragging rights)

You should be able to get a demo of the DAD without buying it first. Then return it if you don't like it. One never pays a restocking charge if you're really a heavy ass recording pro. If this demo is not available from one source, go to a different one or deal with the company directly. You're the customer.
Unfortunately, one pays a heinous penalty for Euro gear now because of the weak dollar.

I would avoid the StageTec design since it is using the frowned on "gain-ranging" technique. This is a technique used to lower noise but one pays a penalty as two converters are used overlapping one another. When one converter runs out of gain and the other converter switches in, there is added gain jumping and distortion.

Despite my long time interest in these subjects, it is clearly evident that these products and working methods have failed to gain traction in the marketplace.
Is there a reason?

( my final word on the subject)
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Old 27th April 2008   #148
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Quote:
Originally Posted by Plush View Post
Quote:
Originally Posted by Plush
The Neumann system, the StageTec system and all others just amplify the mic signal digitally.
Then Jason West replied:
Yes, and this is the function I don't need. I want to record directly to computer so the "line-level outputs synthesized by digital amplification" is irrelevant to my needs.
===================================================

Now hold on a second, bro. Of course you need it--otherwise you won't hear anything.

Probably another miscommunication and we're talking about 2 different things. To clarify, I don't need any line-level analog outputs when recording directly to the computer. On my mic preamps that have digital output, I don't use the analog line-level jacks.

Quote:
You should be able to get a demo of the DAD without buying it first. Then return it if you don't like it. One never pays a restocking charge if you're really a heavy ass recording pro.
I'm not a big shot recording professional. To add to the difficulty, there are no actual physical units in the USA available for demo purposes at this time. Perhaps I should just take the plunge and buy one. And then I could rent it out myself. Who wants to try it out?


Quote:
Despite my long time interest in these subjects, it is clearly evident that these products and working methods have failed to gain traction in the marketplace.
Is there a reason?
Maybe because of inertia. Maybe because the resultant products are truly terrible. May the mic-level AD idea is truly terrible. Hard to say at this point. Not enough products out there yet to form a definitive conclusion in my mind.

I remember the fierce debates about digital vs analog home recording during the Alesis ADAT days (1993). Today, that argument is yesterday's news. Virtually all home studios these days record digital instead of 4-track or 16-track analog tape. If one looks at all those old debates 15 years ago (they're archived on google), he would see several examples of people dismissing "digital" because the ADAT was a harsh sounding product. It was very hard back then for people to look past the ADAT (as a product) and isolate the merits of digital technology on its own. Well, digital recording did have a future in home studios---but you wouldn't have guessed it from some of the ADAT hatred that was going on back then.

Thanks for warning me about the Stagetec TrueMatch.
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Old 27th April 2008   #149
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Quote:
Originally Posted by Jason West View Post
As I already guessed--a misunderstanding. A few weeks ago, I told a 20-something year-old kid, "there's no point for you to repeat it--you sound like a broken record". He didn't know what a "record" was. I need to upgrade both my cliches and my mic preamps!
Oops - my age shows... I immediately knew what Plush was referring to...

StageTecs Truematch technology has been around for quite a while - longer than Neumann's digital mics, if I'm not seriously mistaken. BTW, Plush, the term is "gain staging"...

Beyer was somehow way ahead of their times - these mics did not last long on the market and are indeed quite rare today.

Daniel
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Old 30th April 2008   #150
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Originally Posted by aracu View Post
Andy, I like all the elements, which seem to work well together in the particular recording, great performance, expressive music, unusually wide image, large dose of reverb without losing clarity, ideal mic signature. It may have been partially accidental, but the image is well centered and makes the quartet sound huge. As for the mics I think you are really onto something. My apologies to the original poster for having strayed from the topic.
In the interests of bringing this back to the purpose of the original poster's topic, this orchestral clip was also recorded to two channels of the m-audio delta1010 I mentioned previously.

This consumer level converter was never state-of-the-art, nor even decent many years ago when I bought it. It has a high noise-floor and is somewhat muddy sounding. But it was cheap, functional, reliable & even disposable.

I only post this in order to highlight the emphasis given to conversion technology, an emphasis that is hardly proportional to the actual importance.

Would the clip have sounded a lot better with a Lavry? Of course.

Andy
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