the "sound" of a digital mixer

[massimo]

Sorry for boring you with a question I have already posed when replying to other threads. I would highly appreciate your help.

Since I do not want to use a computer while tracking and mixing (I have a standalone hardisk recorder), I am still interested in hardware digital mixers. I currently own a Yamaha 03D that has - sad to say - served me very well as I have always avoided to use its analog frontends (a/d converters and micpreamps).
I am considering upgrading (candidates include Yamaha DM1000 and Tascam 3200).
Besides the obvious fact that in this forum everyone apparently hates digital mixers - for some good reason I guess - I have two simple questions for you gearslutz:

1. Is a digital mixer supposed to have a "sound" of its own if you do NOT use its A/D's, D/A's, mic preamps and processing (eq, dynamics etc.)? When people say "this sounds good" or "that other sucks", what do they refer to? I am just looking for something that will not degrade what I have recorded using good outboard, and that will handle the routing, connectivity, levels, panpots and scene recall etc. as if it were a computer. I guess it is not a lesser option than mixing in a computer, sound quality-wise. Or am I wrong?
2. Does it make any sense to imagine to take - say - 16 lightpipe channels out from the mixer, convert them to analog via outboard, and sum with a folcrom? (Again have the mixer do the computer job, but experimenting with summing OTB)

thank you very much
best regards
Massimo

[DaveH]

This may start a debate, but guys this is a quick overview of why
digital “can” sound different. (Pages could be written about this.)
Also because this message is so short it leaves all the real details out.
I hope this is helpful and not misleading due to “lack of details”

Part 1 of your question: how can a digital mixer have a sound of its own. .

:
AUDIO ENGINE
Here are some different “audio engines” yes they will sound different.
These “audio engines” can be implemented in software (programs) on a PC
Or they have dedicated hardware (DSP’s). (Like ProTools cards)

These audio engines may internally process data, (handle math), in various ways.
Engines may do this “math” commonly using 32-bits – 56 bits floating point math.
I.E. Cubase SX has a 32-bit engine.

There are several DSP chips using 56 bits.
Soundscape
- 56 Bit Mixing Engine
- Hybrid DSP + native operation

(A long discussion could be started about 32 bit internal processing, is it enough?)
BUT VARIOUS AUDIO ENGINES DO SOUND DIFFERENT!


DITHERING
Also when converting between number of bits.
24 to 16

Does software/firmware/hardware
a. round
b. truncate
c. dither
When dithering what type of noise is added?

Good quick overview here:
http://www.pcrecording.com/dither.htm
http://en.wikipedia.org/wiki/Dithering

ONE TYPE OF DITHERING OVER ANOTHER DOES SOUND DIFFERENT.


Here’s a paper that talks about digital audio in general and
about CD player specifically.

http://www.tc.umn.edu/~erick205/Papers/paper.html

Sampling,Aliasing,Quantization,Dither,Jitter sections could be of interest.
some of these items are more for discussions about A/D and D/A conversion.

Hope this helps in some small way.

[DaveH]

Hi,

Part 2: “Does it make any sense……… “

This is what I am doing right now. Does it make sense? I
sure hope so!

Although I’m new to this forum, I’m not new to having a studio.
First “nice” project studio was built in “83”.

I am doing this type of experiment for myself. I am in the process of building
my long awaited dream studio next-door on an empty two acre lot.
(From ground up). This will have something like an AWS-900 or a D-Control.

While waiting for this “real” studio I didn’t want to sit for a year twiddling
thumbs. So I have s small area that I am bringing in various pieces of equipment
to “learn” during the next-store building process.

I have two DM-24’s and two MX-2424’s and for me there will be
no more Tascam. The Dm’s pres are so-so and the effects were a waste.
(It took time and money for me to find this out.) Support for the MX-2424
was dropped at the mention of their new unit which is not out yet.
(I am in the woods in Northern California and I have to take long trips to
actually hear any of the high end equipment.

I bought the Mackie DXB.
(There were some major problems reported on this unit in earlier
threads here on gearslutz when it first came out.) There have been both firmware and
hardware updates to the DXB and I have had no problems so far. (1 month)

Here’s why DXB for me:
You can configure the I/O as you like.

I have 32 channels of AES in and out. (4 cards) (8 in/out for external effects)
24 channels of TDIF/Lightpipe in and out (3 cards)
24 channels of firewire in and out. (1 card)

I didn’t want Mackie’s A/Ds and D/A’s
so I added 32 channels of Apogee (2)AD-16x / (2)DA-16x.

Yes this is a PC inside, but is has dedicated DSP’s on a separate card.
(To be clear the DXB has it own DSP card, and the UAD-1 is a seperate
DSP card that I added to run the UAD-1 plug ins.) (Total 2 DSP cards.)

I currently have the waves diamond and the UAD-1 ultra pak running on the DXB.

I have a fairly nice list of external boxes that I will be testing against each other as well as against the plug-ins.

I've type too much here, now back to work.

[Lawrence]

Interesting topic.

Everything stated above is true and can cause differences in sound. I agree completely. One of the things often overlooked with digital mixing is the impact of mixing with too much of your eyes as it can distract or interfere with what you hear.

I use a d8b and SX and I had to train myself to periodically close my eyes to remove the distraction from the dual monitors. Never had that problem with my old analog board.

Good topic.

Lawrence

[massimo]

Thanks Dave for alerting me on the existence of the Mackie DXB. While being beyond my budget, that console represents a philosophy that I have often embraced - or better dreamed of- on these pages: that of a digital console where you do not necessarily have to spend on lots average mic pres and converters that you will never use. This one, as far as I can guess, you can tailor based exactly on your interfacing needs, including that of having no analog frontend at all. This is clever, and I wish other companies followed this route, maybe for some less money.
So again guys, I do not want to use a computer. I do not want fan noise in the environment where I also track. I like a hardware mixer. Are you sure that a minimalistic, digital-only use of a digital mixer like what I do (and have described above) is sonically a cheaper option than mixing inside a computer? And, again, does anyone - besides Dave - have experimented with external summing after a digital console? By the way, the Tascam DM3200 seen "in person" seems a whole other story, so much more a serious piece of gear than their DM24.
Best regards
Massimo