ADC - Analogue to Digital conversion

[swampfire]

I just made an offer on the Graham Slee Amp 2 SE on Audiogon. Wish me luck!

 

I think the only way this music will have the same emotional impact now that it did 35 years ago is if I quit taking Prozac. Again, wish me luck! I'm very serious friends...the brain is the last filter....

[gmgraves]

While there is a lot of useful information on DACs in the Equipment forum it is hard to track down info on ADCs.

 

I am sure that there are many computer audiophiles out there who in addition to wanting the best sound from their digital source material stored on hard disc or optical disc, would like to have access to their collection of music on LP in hi-res digital form.

 

User experiences of outboard ADCs (aka audio interface boxes) and internal ADCs (aka sound cards), particularly the comparative quality of sound, would therefore be very useful for those wishing to digitise LPs and other high-quality analogue sources.

 

HOW ABOUT A SECTION IN THE EQUIPMENT FORUM ON ADCs?

 

Here is a starter for this subject:

 

I am in the process of deciding how to archive my music collection on LP.

 

As a first attempt I have used the internal ADC on my Mac Pro, running Peak Pro software, to digitise the signal from my phono amp (Pure Sound p10), with the signal level adjusted externally to prevent limiting. The results sound OK but I suspect that I could do better if I had a better quality ADC.

 

I first looked at external Firewire ADCs as these would avoid the noisy computer environment and not tie me down to one computer. I found few ADCs designed for Hi Fi use on the market; there appears to be nothing between the Project USB phono stage (~ £100) and the Benchmark ADC1 (~ £1700). I therefore looked at hardware designed for recording live music e.g. the Firewire audio interfaces made by Apogee (Duet) and Edirol (FA-66). These have good reviews in the community they serve but I am not sure how appropriate they would be for archiving music from LPs.

 

Because of this uncertainty I looked again at sound cards. The Lynx L22 has had good reviews for sound quality but unfortunately only comes as a PCI card; I require a PCI Express card for the Mac Pro. The RME HDSPe AIO looks a suitable candidate as it is 192 kHz-capable and has had favourable comments on its audio performance in professional recording magazines.

 

Any comments or suggestions would be much appreciated.

 

David

 

Does your Mac have Firewire (most do). If so. might I suggest that you give the Behringer F-Control Audio FCA-202 computer interface/A/D converter a try? It's been recently discontinued, but I'm sure you can find one if you look around. It's relatively cheap at under US$100 and it is 24-bit/96KHz. I have used it in conjunction with the program Audacity to make some fine live recordings and the results are excellent, with very low latency - easily as good as any pro gear. I think you will find it more than adequate for archiving LPs, analog tape, and radio broadcasts.

 

http://tinyurl.com/m58ggfz

[bdiament]

Hi David,

 

While there is a lot of useful information on DACs in the Equipment forum it is hard to track down info on ADCs.

 

I am sure that there are many computer audiophiles out there who in addition to wanting the best sound from their digital source material stored on hard disc or optical disc, would like to have access to their collection of music on LP in hi-res digital form.

 

User experiences of outboard ADCs (aka audio interface boxes) and internal ADCs (aka sound cards), particularly the comparative quality of sound, would therefore be very useful for those wishing to digitise LPs and other high-quality analogue sources.

 

HOW ABOUT A SECTION IN THE EQUIPMENT FORUM ON ADCs?

 

Here is a starter for this subject:

 

I am in the process of deciding how to archive my music collection on LP.

 

As a first attempt I have used the internal ADC on my Mac Pro, running Peak Pro software, to digitise the signal from my phono amp (Pure Sound p10), with the signal level adjusted externally to prevent limiting. The results sound OK but I suspect that I could do better if I had a better quality ADC.

 

I first looked at external Firewire ADCs as these would avoid the noisy computer environment and not tie me down to one computer. I found few ADCs designed for Hi Fi use on the market; there appears to be nothing between the Project USB phono stage (~ £100) and the Benchmark ADC1 (~ £1700). I therefore looked at hardware designed for recording live music e.g. the Firewire audio interfaces made by Apogee (Duet) and Edirol (FA-66). These have good reviews in the community they serve but I am not sure how appropriate they would be for archiving music from LPs.

 

Because of this uncertainty I looked again at sound cards. The Lynx L22 has had good reviews for sound quality but unfortunately only comes as a PCI card; I require a PCI Express card for the Mac Pro. The RME HDSPe AIO looks a suitable candidate as it is 192 kHz-capable and has had favourable comments on its audio performance in professional recording magazines.

 

Any comments or suggestions would be much appreciated.

 

David

 

Choice of an ADC will be very much like choice of a DAC, insomuch as what is "best" will vary depending on exactly what it is one seeks.

My own experience has been that all converters (ADC as well as DAC) tend to fall into one of three "schools". One's sonic goals will determine which of these schools will contain the most appropriate choice.

 

To wit, one of the most populated of the schools, to my ears, is what I call the "enhanced detail" school. Converters in this group tend to emphasize detail (and as a result will often get rave reviews in the audio press and on line). Only thing is, the "detail" they emphasize is not contained in the input signal and is generally just the addition of spurious harmonics (which in the old days, was referred to as "distortion"). Still, some folks find this sort of sound to add excitement and I'd never argue with whatever brings someone their listening pleasure.

 

The second school, which I call the "silky smooth" school, seeks to avoid the rough edges of much digital (such as the converters in the first school display) and rounds out those rough edges, warming up the sound with what some deem a golden "analog glow" (perhaps reminiscent of some older tube electronics). Only thing is, these tend to round out *all* the edges, whether rough or not. Again, a departure from what is contained in the input signal. These can make not-so-great recordings more tolerable but what they do to those recordings is exactly what they do to recordings that do not need any "smoothing" too.

 

Lastly, in my experience, a very sparsely populated school, the one I call "get out of the way". Converters in this group, admittedly still a tiny one even today, reveal the input signal, for better or worse. There is nothing like them for hearing just how good the better recordings are. On the other hand, they provide the same clear window on the not-so-good recordings. That said, in my opinion, they still get the best out of any recording but this is only a good thing if that is what one seeks -- a converter that reveals the input, without editorializing.

 

To be clear, there are a great many converters today, regardless of school, that sound "very good". My personal point of view is this is exactly what I don't like about them. My own preference is for gear that doesn't "sound" at all but simply presents the sound of the input signal. This is the only type of gear in my experience that will reveal the full extent of the differences between recordings.

 

Now that's me. Of course, you may hear it similarly or you may hear it differently. The best way to find out is to listen for yourself and draw your own conclusions. That said, I would very highly recommend one of the interfaces from Metric Halo. I've used and loved all of them. The 2882 might tend ever so slightly toward that first school, the ULN-2 just a bit toward the second and the LIO-8 (and ULN-8) very much in the third school (which it may well own in my opinion, as it is the first converter I've heard where, when used at 24/192, I have not yet been able to discern the output from the input).

 

Each of these Firewire interfaces serves as ADC, DAC, preamp, (nothing less than superb)RIAA decoding and recording software (plus more than will fit in this post). I currently do all my recordings with my ULN-8 capturing audio using the Record Panel in the software that comes with all of the Metric Halo boxes (called "mobile i/o" or MIO). Peak Pro is an excellent application for taking the individual mono channels produced by the Record Panel and joining them into interlaced stereo files. (I record to .aif format and have used Peak Pro to create the stereo .aif masters.)

 

You can plug the output of your phono cartridge directly into the MIO, bypassing your hardware phono preamp and go directly to very high quality digital.

Their customer service is top notch as well. They also have their own forum where questions are often answered by the designer himself.

 

If the LIO/ULN-8 is outside of the budget, I would very much recommend auditioning a ULN-2. I'd rather have one of those than something from another designer at 10x the price.

 

Hope this helps.

 

Best regards,

Barry

Soundkeeper Recordings

The Soundkeeper | Audio, Music, Recording, Playback

Barry Diament Audio

[swampfire]

I'm of the "weakest link" school: all components in the conversion chain should be reasonably well-matched in terms of quality and budget. Most of the LPs I'll be converting are fairly well-worn. I think I'll be happy with this as my final setup:

 

Music Hall MMF-5

Ortofon 2M blue

Graham Slee Amp 2 SE

Sony PCM-M10

Very small tweaks via DSP on the computer

 

The latter would include click and pop removal (for heavily worn vinyl) and maybe a rumble filter.

[Panelhead]

An analog phono stage will add color to the sound. Unless really good. The software based phono EQ should be much cheaper for the same level of performance.

I want a Metric Halo. For now a TC Impact Twin and Pure Vinyl will do. The Impact Twin is clean and has decent mic pre-amps for gain. Plus great clock.

This is where the low dollar pro interfaces are weak, mic pre-amps.

[DavidL]

Does your Mac have Firewire (most do). If so. might I suggest that you give the Behringer F-Control Audio FCA-202 computer interface/A/D converter a try? It's been recently discontinued, but I'm sure you can find one if you look around. It's relatively cheap at under US$100 and it is 24-bit/96KHz. I have used it in conjunction with the program Audacity to make some fine live recordings and the results are excellent, with very low latency - easily as good as any pro gear. I think you will find it more than adequate for archiving LPs, analog tape, and radio broadcasts.

 

Behringer F Control FCA202 FireWire Audio Interface

 

Thanks George but please see my post #9 from May 17 2009 - I've been using a Fireface 400 firewire audio interface since then.

At the moment as I'm investigating streaming I'm using it as a firewire-to-SPDIF converter, but intend to get back to digitising LPs in the not-too-distant future.

David