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[klarkin]

I am having a very hard time discerning the differences between various converters and would like to know exactly what is the best way to do a comparison. I either have the worst hearing on the face of the earth, or the differences between these converters are so sutle that only trained engineers can hear what I am trying desperately to hear.

Hearing others talk about how "their sound opened up", or "the stereo image widened," and "better bass response." And my favorites, "it blew my other converter out of the water," or "it's like someone pulled a veil off of my speakers!"

Well, I'm not hearing hardly anything!! Sometimes I think I hear the difference, but then I listen again and nada! Someone please tell me that I'm doing the shootout wrong.

Aside from doing comparisons in a highly designed professional studio, or an Anechoic chamber, someone give me some directions. Does anyone in Los Angeles want to do the shootout with me in their professionally designed studio? I will bring my gear that I am comparing, which is my old Apogee AD8000 with 8 channel D/A installed,  my Benchmark Media DAC1, and a new Rosetta 200 AD/DA I just purchased. I also have a Apogee Big Ben that I am using in the test to see if any of the converters sound better by being clocked to it or not. Any of the pro's want to chime in? How about Max @Apogee, or Atticus from Benchmark Media? Fletcher, any ideas?

To be honest none of the gear is blowing away my AD8000 that I've owned since 1998. The room that I am doing the test in is not treated, but because of all the creative descriptions given by everyone here, I thought that i wouldn't have to be in a controlled environment to hear which is the best. My reasoning is that this is a typical room where people listen to music.

Also, I am using cd's to do the test. My CDR recorder is an old Marantz CDR620. It's about 5 years old. So, I'm assuming the converters aren't the best. But, how can I surpass them to hear what professionally mastered projects sound like? HELP!!

Kenny

[lowland]

Hi Kenny,

I understand your frustration. Part of the problem can be that people are so keen to sell the benefits of 'magic ingredient X' that they sometimes overcook their response to what they've heard - however my experience has been more to do with incremental improvements.

While things do occasionally sound radically better as you upgrade, for me that's the exception: one example might be the changeover I made from using the converters in my dbx Quantum for analogue transfers to those of the Crane Song HEDD - the HEDD's ADCs were undoubtedly better all round, but I had been expecting a scale of difference which simply wasn't there - a useful lesson for me.

FWIW, I've found that rather than listening for obvious tonal differences straight away when comparing converters it has helped me to start by checking out relative graininess or a closed-in feel to the soundstage, and then move on to things such as the low end.

When you mention your CD recorder, does this mean you're taking an analogue feed out out your system and burning CDs from it for comparison purposes? If so that could be a big part of the problem right there, and I would have thought it would be better to listen 'live' 24 bit while switching between various setups. A good set of headphones might help too.

[thedoc]

This may sound funny and is subjective, but....

Try recording jangling car keys and see which convertor handles it best.  This test can really show off the weakness of a system.  Be sure not to clip...  I think this test will surprise and amaze.

[Joe Crawford]

Yea Doc, that’s a great test.  But it’s hard to keep the mic out of the picture.  Car keys usually show up limitations in the microphone before they even get to the converters.

Joe Crawford
Stony Mountain Studio
Shanks, WV  26761

[Johnny B]

Some people after hearing Lynn's shootout CD rated as follows:

1. Manley Slam with 192 option
2. Weiss
3. Lynx II

Of course, YMMV.

[Bob Olhsson]

It's common to listen for the wrong things. I have a problem with the "blows away" comparisons myself because they are frequently more about how the analog stage interfaces with what follows it than digital artifact issues.

Things to listen for are musical balance, how much kick is there, how loud are the guitars, is vocal distortion being revealed or covered up.

Listening to a CD doesn't address any of these issues nearly as much as making different mixes based on what you hear from each converter.

[Max]

Bob Olhsson wrote on Mon, 04 April 2005 18:38

It's common to listen for the wrong things. I have a problem with the "blows away" comparisons myself because they are frequently more about how the analog stage interfaces with what follows it than digital artifact issues. Things to listen for are musical balance, how much kick is there, how loud are the guitars, is vocal distortion being revealed or covered up. Listening to a CD doesn't address any of these issues nearly as much as making different mixes based on what you hear from each converter.

All true, but you can't really separate the analog section from the rest as it all plays a part in the conversion process, as you know.

I wanted to add to Bob's statement a bit. When listening to converters, it is important to be referencing a quality analog source. Comparing the sound of converters to each other really does not mean a whole lot, it is how they sound in reference to what they are converting that counts. The converter that is closest to the source and makes the best compromises in terms of where the loss is placed is what should be listened for.

Material you are familiar with is always better. With converter listening, you are listening for timbre, placement, clarity and imaging. For example, find a vocal track where the vocal performance is very up front in the mix. Does it stay there when converted or does it collapse back into the track? What about the snare? does the timbre change when converted, and if so how much? how's the center overall? Are things too wide, or where they should be compared to the source? What is the separation like between the bass and kick compared to the source? Find a nice heavy guitar track and listen to the placement of the guitars at the source. How much does it change after conversion? Low mids are where average converters typically fail the most. How's the energy of the overall track after conversion? Does the converter maintain the energy or sound thinner? Listen closely to the low mids and that should tell you a lot about what's going on.

Of course everything should be calibrated correctly and clocked independently. And you should listen blind. If you know which converter you are listening to, it is much harder to be objective. You may be surprised at how many "golden ears" will NOT do a blind test under any circumstances. They don't want to be wrong....

[thedoc]

A dynamic mic will work better than a condenser....you could also do an analog recording in parallel to compare with.

[klarkin]

Max, as per your instructions, I took the dac1 out of my converter comparison. To explain to the others, I originally had my ad8000 going into my dac1 digitally, the rosetta also was patched into the dac1 digitally. The reason being, it has a switch on the front panel to allow quick swithing between the two. number two, it's suppose to be an awesome converter. So, i thought it would reveal the differences between the two converters easily. But, after speaking with Max, he informed me that because the dac1 is in fact upcoverting the music, that it's probably not a good way to compare the converters. i then bought a switcher to do the test. but, i still couldn't conclusively tell the difference between the 3 converters, neither could my brother, or my girlfriend. both of whom are not in the music business. so there wasn't any bias for a particular piece. Max, do you have a room where I can bring down the gear and do a shootout? I am down the street from you in west hollywood.

kenny

[natpub]

Some monitoring and room situations are simply too fuzzy to reveal certain small differences. However, when stacked multiple times across multiple tracks, then played back on a variety of systems, small differences can become more apparent. At least, that is what I found when testing things like this.

[Max]

klarkin wrote on Tue, 05 April 2005 01:36

Max, do you have a room where I can bring down the gear and do a shootout? I am down the street from you in west hollywood. kenny

Hi Kenny,

We are in the process of moving and our lab is torn apart and stacked full of boxes. Give me a call and we can discuss. 310-915-1000 x55

Quote:

Some monitoring and room situations are simply too fuzzy to reveal certain small differences. However, when stacked multiple times across multiple tracks, then played back on a variety of systems, small differences can become more apparent. At least, that is what I found when testing things like this.

Absolutely. The differences are cumulative. The more tracks being listened to, the easier it is to discern the variation between converters, clocks etc.

[Johnny B]

Max wrote on Mon, 04 April 2005 23:19

Low mids are where average converters typically fail the most. How's the energy of the overall track after conversion? Does the converter maintain the energy or sound thinner? Listen closely to the low mids and that should tell you a lot about what's going on.

This seems to be true and good advice.

[Level]

Actually, I look toward depth of field and darkness. I prefer a "blacker background" and more dynamics.

Well at least, this is what I feel is better...more dynamics and less hash.

[Bob Olhsson]

Actually you can hear a lot of digital artifact and balance issues on Auratones or NS-10s. It doesn't require tweako monitors at all!

We aren't talking about colorations in the analog sense. It's stuff like being able to hear the high hat with one converter and not with the other yet one doesn't sound particularly brighter than the other.

[Dave Peck]

klarkin wrote on Mon, 04 April 2005 03:38

I am having a very hard time discerning the differences between various converters and would like to know exactly what is the best way to do a comparison.  HELP!! Kenny

When trying to discern the difference between good converters, it's important to use high quality source material. Preferably something like a first generation analog recording of a real live acoustic source, such as a vocal group, grand piano, acoustic guitars, etc, with simple & accurate stereo micing that captures lots of transient details and real acoustic ambience.

Connect the analog source to one input of an A/B switch, and also connect it to the analog in of the converter. Now loop the dig out of the converter to the dig in, and connect the converters final analog out to the B input of the A/B switch. "A" is direct analog, "B" is the analog signal passed through the entire A/D-D/A chain of the converter.

Then, A/B each converter against the source, not against another converter. The most accurate converter will be the one that sounds most like the analog source, not the one that sounds subjectively 'better' than another converter.

Using this technique, watch for things like a sudden widening or narrowing of the stereo image when you switch from analog source to converter. This can indicate a shortcoming in the converter's ability to accurately reproduce transient detail that is necessary for accurate stereo imaging, among other things.

During 2002 & 2003, I performed this type of testing (among other duties) for a high end converter manufacturer on a weekly basis, and in my experience, this type of testing can be very revealing. These tests were performed using first gen analog master tapes, Spectral power amps, and Avalon speakers, which have very good imaging.

Of course, the test will be more revealing if you use  speakers that are capable of accurately reproducing fine imaging details, but some folks can succesfully perform tests like this using somewhat less revealing speakers. It helps if you're familiar with the speaker.

We also discovered that when you use a high quality analog source and a revealing playback system, and compare the converter to the source, not another converter, even barely measureable differences can be quite audible when you hit the A/B switch. You don't have to be a golden ear to hear the difference. If there is anything wrong, most people can hear it.