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Gear / Technical Help => Battery Boxes, Preamps, Mixers, ADCs, and Processors => Topic started by: keytohwy on August 18, 2013, 11:37:45 PM

Title: ADC preference?
Post by: keytohwy on August 18, 2013, 11:37:45 PM
I've got a Busman mod UA-5 to use for A/D from a Nakamichi Dragon.  But I've also been looking at a Lucid AD9624.  Any thoughts on preference?  I've never run the Lucid, just been reading reviews.  Any others you'd recommend?
Title: Re: ADC preference?
Post by: noahbickart on August 18, 2013, 11:53:13 PM
Price range?

I doubt that you'll do much better than the mod UA-5 unless you want to look at units which cost alot of money. However you might be able to find a used mini-me for ~$450 and there is a used v3 in the yard sale for ~$750
Title: Re: ADC preference?
Post by: keytohwy on August 19, 2013, 12:02:21 AM
Price range?

I doubt that you'll do much better than the mod UA-5 unless you want to look at units which cost alot of money. However you might be able to find a used mini-me for ~$450 and there is a used v3 in the yard sale for ~$750


I want to get the best reasonable A/D.  These are analog masters/1st gens of audience tapes from 70s to 90s.  The best A/D in the world won't make up for some of the limitations of the original gear.  I want to do these transfers once.  Not now, then again in a couple of years when I get "better" gear.
Title: Re: ADC preference?
Post by: page on August 19, 2013, 01:04:24 AM
I love the Sound Devices ADCs they've used (in the 7 series and usbpre2), but unless you need a usbpre2 for something else (head amp, dac, preamp/adc, etc) then it doesn't make much sense. Apogee had a small unit after they axed the minime that might be interesting to look at.

Really, a Sony M-10 will do the job, and unless you've modded your analog stage of the ua-5, the m10 will likely do a better job. I could tell a difference when a comp was done with the m10 against the 722, but it wasn't a slouch.
Title: Re: ADC preference?
Post by: H₂O on August 19, 2013, 03:00:55 PM
7xx series is more than enough


Could consider minime, or even a Mytek stereo adc96 (about $500 on eBay nowadays)?


The Mytek is not a field unit though
Title: Re: ADC preference?
Post by: keytohwy on August 19, 2013, 03:08:12 PM
Yeah, don't need field...should have said that.  I own the UA-5 already, but portable not a requirement.

Thanks for the info everyone!
Title: Re: ADC preference?
Post by: stober on August 23, 2013, 02:44:45 PM
Mytek Stereo 192 can be used in the field but if you just need something at home for analog audience masters a Mytek stereo ADC 96 will do the trick I bet. Depends on how much you wanna spend. Here's a Mytek Stereo 192 on ebay for a good price.http://www.ebay.com/itm/Mytek-Stereo-192-ADC-/141039640938?pt=US_Computer_Recording_Interfaces&hash=item20d69e216a  Cheaper than what I got mine for used.
 Here is a Mytek stereo 96 on ebay. http://www.ebay.com/itm/Mytek-Stereo96-ADC-Analag-To-Digital-Converter-/300952461178?pt=US_Computer_Recording_Interfaces&hash=item46122a1f7a
 Main differences is the 192 is 24 bit only and can be battery powered in the field. The 96 will do 16 bit as well as 24 bit but cannot be used with a battery option.. Love the mytek ADC.
Title: Re: ADC preference?
Post by: jerryfreak on August 23, 2013, 05:22:59 PM
how many tapes we talkin? i an loan my ad2k.....
Title: Re: ADC preference?
Post by: keytohwy on August 24, 2013, 01:13:21 PM
how many tapes we talkin? i an loan my ad2k.....

Thanks, Jerry.  I'll send you a PM.  I need to comb through the tapes...some aren't masters, and circulate otherwise, so I'll dump those.  Probably about 50-60 hours worth.  I should be able to knock it out in a couple of weeks, once my ducks are in a row.

Very kind offer, than you again.
Title: Re: ADC preference?
Post by: DSatz on August 25, 2013, 10:19:15 AM
If the Lucid is reasonably priced and in good condition, I think you could be happy with it. Mytek is also a good candidate. Both can be driven by single-ended (unbalanced) outputs such as those of the Dragon (that's what I use, too). Among older pro converters that work well, you could also look out for various Symetrix and Apogee models.

For cassette transfers, of course, there's no need for high sampling rates or extended bit depth; 12-bit resolution would be more than enough, if it were available! Anything else is just using more bits to convey the same information.

--best regards
Title: Re: ADC preference?
Post by: keytohwy on August 25, 2013, 01:34:56 PM
If the Lucid is reasonably priced and in good condition, I think you could be happy with it. Mytek is also a good candidate. Both can be driven by single-ended (unbalanced) outputs such as those of the Dragon (that's what I use, too). Among older pro converters that work well, you could also look out for various Symetrix and Apogee models.

For cassette transfers, of course, there's no need for high sampling rates or extended bit depth; 12-bit resolution would be more than enough, if it were available! Anything else is just using more bits to convey the same information.

--best regards


There was a Lucid locally on Craigslist last week, but I passed.  Seems with a little patience, they are available under $250.

As for the bit depth, can you share any more info/links on that?  I had planned on 24/48 transfers.
Title: Re: ADC preference?
Post by: noahbickart on August 25, 2013, 03:57:19 PM
For cassette transfers, of course, there's no need for high sampling rates or extended bit depth; 12-bit resolution would be more than enough, if it were available! Anything else is just using more bits to convey the same information.

--best regards

Dsatz is, of course, correct. I might add, however, that if you used a 12 bit recorder (if such a thing existed) you would have to be somewhat careful about setting levels (e.g. hot) such that you take advantage of even those 12 bits. With a 24 bit recorder, you can set levels much more conservatively and still be assured of capturing all the data. Just Normalize and Dither to 16bit when you are done.

I use 24bit for everything. Not because it "sounds" better, but because it makes it harder to get hard overs, and does sound better than limiting which would be the other obvious way to prevent digital clipping.
Title: Re: ADC preference?
Post by: jazzgtrl4 on August 26, 2013, 10:21:15 AM
Out of your price range I'm sure but I just bought one of these used  i use it for playback, transfers, studio protools rig,  in the field  (not yet but can be battery powered)...sounds incredible

http://www.lynxstudio.com/product_detail.asp?i=59
Title: Re: ADC preference?
Post by: DSatz on August 26, 2013, 08:17:18 PM
If you have some reason for using 48 kHz sampling, then by all means, use it. I don't, because for me the audio CD is still the "gold standard" medium for music distribution to other people in general, not just audio nuts like myself.

Noah is quite right, but 16-bit depth is more than enough to give you complete safety as far as headroom is concerned. Cassettes, even if optimally recorded with Dolby "C" noise reduction and Dolby HX on pure metal tape, never quite reach a 70 dB dynamic range. So you could transfer the recordings with the absolute peaks set at -10 dB and still be more than 10 dB above the converter's noise floor at all times. Using more bits under those conditions gains you nothing.

--best regards
Title: Re: ADC preference?
Post by: page on August 26, 2013, 08:33:46 PM
Its related to the low level noise inherent in the medium. I swear cassettes top out at around 65db of dynamic range before you either saturate the tape or hit the tape noise.
Title: Re: ADC preference?
Post by: keytohwy on August 26, 2013, 09:27:21 PM
All good info...thanks everyone.  I'll probably capture are 24/48, still, edit, then dither as the last step. 
Title: Re: ADC preference?
Post by: datbrad on September 01, 2013, 10:13:21 PM
My buddy Mark transfered a bunch of my '80s GD cassette masters running them on Nak CR7>Lucid AD2496 (output 16bit)>Fostex D5 dat and I think the Lucid sounds really nice. The Lucid DA box is also great sounding to my ears.
Title: Re: ADC preference?
Post by: F.O.Bean on September 02, 2013, 02:37:47 AM
My buddy Mark transfered a bunch of my '80s GD cassette masters running them on Nak CR7>Lucid AD2496 (output 16bit)>Fostex D5 dat and I think the Lucid sounds really nice. The Lucid DA box is also great sounding to my ears.

If transferring cassette tapes, why use 16bit and not 24bit for MAX quality?

Thanks,
Bean
Title: Re: ADC preference?
Post by: page on September 02, 2013, 11:48:09 AM
If transferring cassette tapes, why use 16bit and not 24bit for MAX quality?

Posts 9, 13, and 14.
Title: Re: ADC preference?
Post by: noahbickart on September 02, 2013, 01:12:17 PM
My buddy Mark transfered a bunch of my '80s GD cassette masters running them on Nak CR7>Lucid AD2496 (output 16bit)>Fostex D5 dat and I think the Lucid sounds really nice. The Lucid DA box is also great sounding to my ears.

If transferring cassette tapes, why use 16bit and not 24bit for MAX quality?

Thanks,
Bean

Cassettes, even if optimally recorded with Dolby "C" noise reduction and Dolby HX on pure metal tape, never quite reach a 70 dB dynamic range. So you could transfer the recordings with the absolute peaks set at -10 dB and still be more than 10 dB above the converter's noise floor at all times. Using more bits under those conditions gains you nothing.
Title: Re: ADC preference?
Post by: F.O.Bean on September 03, 2013, 01:41:29 AM
Gotcha, thanks Noah ;) I havent researched cassette tapes in MANY YEARS, and had no clue about the 70db of dynamic range ;) I remember awhile back folks recording cassette transfers at 24/96, 24/192 and 1bit/5.8mHz ;)
Title: Re: ADC preference?
Post by: datbrad on September 03, 2013, 08:07:34 AM
The cassette transfers using the Lucid I mentioned were done 2000-2001, the primary reason 16bit was used. As Dsatz pointed out, 70db dynamic range cassettes don't require 24 bit resolution, nor higher than 44.1khz sampling. Higher bit depths would be appropriate if editing needed to be done in post. If I was transfering reel to reel tapes, I would absolutely use 24bit.

To clarify 70db dynamic range is about half the range of human hearing, but for perspective consider a classical performance in a theater might reach 85db on a piece like the 1812 Overture, but PA reinforced rock concerts only realize dynamic ranges around 50-60db at the most. I am pointing this out because many have the notion that 24bit recording always excels over 16bit, and that is not always true.



Title: Re: ADC preference?
Post by: noahbickart on October 04, 2013, 08:16:13 AM
Gotcha, thanks Noah ;) I havent researched cassette tapes in MANY YEARS, and had no clue about the 70db of dynamic range ;) I remember awhile back folks recording cassette transfers at 24/96, 24/192 and 1bit/5.8mHz ;)

And you *can* cut room temperature butter with a samuri sword. But the ensuing toast tastes no better.
Title: Re: ADC preference?
Post by: twatts (pants are so over-rated...) on October 04, 2013, 08:31:16 AM
Gotcha, thanks Noah ;) I havent researched cassette tapes in MANY YEARS, and had no clue about the 70db of dynamic range ;) I remember awhile back folks recording cassette transfers at 24/96, 24/192 and 1bit/5.8mHz ;)

And you *can* cut room temperature butter with a samuri sword. But the ensuing toast tastes no better.

Don't tell that to this guy...

http://www.youtube.com/watch?v=CQxHe2CT-ec

Terry
Title: Re: ADC preference?
Post by: Gutbucket on October 04, 2013, 11:51:53 AM
Higher bit depths would be appropriate if editing needed to be done in post.

They are, however you needn't capture unnecessary extra bits to edit using additional bits.  Editing in software is almost always automatically done at a higher bit depth internally than that of the original file, and the final output truncated/dithered back down again when the output files are saved, which may or may not be the same rate as the original file.


And you *can* cut room temperature butter with a samuri sword. But the ensuing toast tastes no better.

Although the marmalade's revenge makes for a sweet toast of success.
Title: Re: ADC preference?
Post by: datbrad on October 13, 2013, 12:04:54 PM
I may be wrong, but I'm fairly sure that 32bit floating-point processing is not going to pull the same info from analog tape master made at 16bit as it can from a 24bit fixed point master of the same tape. But I think there is another reason using 24bit might be better.

Expression of dynamic range for a cassette, or any analog tape for that matter, is different than the same measurement in PCM. Both are based on the point the noise floor is reached, however with digital it goes from signal to complete noise at a fixed point, and clips to all distortion at a fixed point. With analog, the same cut offs apply for SNR and dynamic range, but there is musical information above the clip point and into the noise floor on analog tape not included in the numbers, but audible. It seems better to me to use 24bit, however I have no plans to re-do any of the transfers of my cassette masters already done in 16bit with so many more still to transfer. I will do 24bit going forward I think.
Title: Re: ADC preference?
Post by: Gutbucket on October 14, 2013, 10:32:49 AM
I may be wrong, but I'm fairly sure that 32bit floating-point processing is not going to pull the same info from analog tape master made at 16bit as it can from a 24bit fixed point master of the same tape.

32bit floating-point is not 'pulling more information out' of the analog tape, its simply providing increased processing precision for calculations made after the information has been digitized.  That processing precision ‘headroom’ is only needed while doing the calculations.  It’s unnecessary to either capture that range or output it after the calculations are made, it simply avoids ‘rounding errors’ during the processing.

Quote
Expression of dynamic range for a cassette, or any analog tape for that matter, is different than the same measurement in PCM. Both are based on the point the noise floor is reached, however with digital it goes from signal to complete noise at a fixed point, and clips to all distortion at a fixed point. With analog, the same cut offs apply for SNR and dynamic range, but there is musical information above the clip point and into the noise floor on analog tape not included in the numbers, but audible.

As long as the digital dynamic range fully encompasses the entire dynamic range of the analog source, including those non-linear distortions at the extremes of the analog range, it can fully encode all the information. The digital range just needs to be as large as the entire analog range, with levels adjusted so that full analog range fits comfortably within the digital range.  Just use a digital range that is large enough to include any ‘soft-clipping’ at the top and decay into noise floor at the bottom.  Inclusion of that extra bit of range still probably fits into 16 bits.

Dither is a good way to think about this, as it allows sounds to be audible and decay gracefully as they fall below the noise-floor, without a sharp digital cutoff point. It’s simply the addition of analog noise. To retain the same measured noise floor when introducing dither, the digital range needs to be extended by an additional bit to encompass the dither.  The digital range then fully encompasses the analog range including the dither and the analog sounds which can be heard to decay into the dither below the analog noise floor.

The digital dynamic range only need be slightly larger than the analog range to completely capture all the information; it doesn't retain any additional useful information by being considerably larger.
Title: Re: ADC preference?
Post by: Gutbucket on October 14, 2013, 02:45:53 PM
a good tape sim algorithm should model noise behavior (together with frequency response, saturation, and wow).

I don't have much experience with tape simulation plugings, but beyond choosing from preset emulations, I wonder how many of them offer seperate controls over the parameters for each of the various distortion algorithms they seek to model, emulating the different forms of measurable tape distortion.  Importantly (and probably as rare as hen's teeth, unfortunately) developers should let the user know what each parameter is exactly doing, and ideally should discuss what use it may have outside an accurate repoduction of tape effects.   For example, some users may be looking for a truely accurate simulation, other's may be looking for an exagerated effect, and others may only want the saturation and dynamic range effects for example and not the noise or wow effects which would be required to make an accurate simulation. 

Those dropouts and that print-through sound sooo realistic!

Imagining a check box for simulating the live recording tape-flip, with drop-downs for choosing tape speed, cassette length, and the degree of taper dexterity (the last perhaps best quantized in beers).
Title: Re: ADC preference?
Post by: page on October 15, 2013, 12:08:10 AM
I wonder how many of them offer seperate controls over the parameters for each of the various distortion algorithms they seek to model, emulating the different forms of measurable tape distortion.  Importantly (and probably as rare as hen's teeth, unfortunately) developers should let the user know what each parameter is exactly doing, and ideally should discuss what use it may have outside an accurate repoduction of tape effects. 

For those who are serious, the UAD set of plugs are the first ones that come to mind with that level of dedication and options. The Struder and maybe the AMPEG ones are where I'd look first. I've used a couple in tests (from Izotope and URS) that had various presets and wet/dry adjustable but that was it. (I'm not trying for accurate reproduction so much as a specific effect so I didn't go further).
Title: Re: ADC preference?
Post by: dogmusic on November 11, 2013, 09:20:37 AM
Since this thread started as a question of ADC preference, I wonder if anyone has an opinion about the quality of the ADC in the TASCAM DV-RA1000HD in comparison to the ones mentioned here like the Mytek, Lucid, and Sound Devices.

I also plan to transfer a bunch of tape and wondered if the TASCAM would be as good.