I own a cheap Audio interface from Steinberg " Ci1 " ( brand: Yamaha )

I just lendt a Focusrite 18i8, audio interface from a friend to check out.

Now i did not think or could imagine that......, it would be that much of a change in the sound
of different audio interface's but just small, and almost unnoticeable differences.

but ups, i almost did it again..

First thing i noticed with the 18i8 was...., it is less sensitive on the inputs ( need more gain ) on the input stage.
it had less bass and treble, compared to the Ci1 and it sounded more mid ranged and " clean "
compared to the Ci1 more " saturated " sound.

What one is more saturated or less saturated is hard to tell, by just two comparison's.

The stereo width, seemed a tad less on the 18i8, and " tighter " in the sound
while the Ci1 is more " loose " and have a wider stereo image
the instruments seems a bit more panned too, compared to the 18i8.

Before i thought it was just to go and buy " whatever " audio interface i would like
if it had good preamp's and enough of inputs and was decent built.
Now i am not certain anymore.

Many talk about preamps, how many input's, analog outputs, digital outs, digital inputs, phantom power etc
and whatever specs they may look for in the Audio interface.

But are we " forgetting " how it may sound ? Probably the most important part !

I would love a good comparison of a few of the most common cheap /mid budget Audio Interfaces like :
Yamaha, Roland, M-Audio, Akai, presonus, focusrite.

So when i need a new Audio Interface, i can't go on a store and tell em i need to " lend " 6 different
audio interfaces ,so i can compare them and decide what to buy..
And i can't afford to buy all 6, and to sell 5 later on.

Soundblend
 
Many talk about preamps, how many input's, analog outputs, digital outs and whatever
specs they may look for in the Audio interface

But what about the sound ?

I would love a good comparison of a few of the most common cheap /mid budget Audio Interfaces like :
Yamaha, Roland, M-Audio, Akai, presonus, focusrite.

I wish it could be that simple! The problem is that "sound" is subjective - just check out the endless forum posts where people debate the "sound" of cables
 
Many people said a particular interface I reviewed had a "warm" sound, which intrigued me. But when I ran specs on it, there was more distortion than on some other interfaces I tested. Was the distortion the reason for the "warm" sound? I don't know.
 
On the other hand, stereo width is something that can be reflected accurately in crosstalk specs. I noticed the TASCAM UH-7000 seemed to have a wider soundstage than other interfaces, but its crosstalk is below -90 dB. I've measured some audio interfaces whose crosstalk spec is more like -55 dB. That's going to make a difference in the stereo imaging.
 
Another factor is the microphone being used. A slight change in input impedance in one audio interface can affect a dynamic mic in one way, yet the same mic in a different interface will sound slightly different. Then the question becomes whether the difference is "better," "worse," or just "different."
 
The best approach is probably to do what you've done - a side-by-side comparison where if you like one interface better than another, then that's the one you should use. Unfortunately there's no easy way to do this unless you can go to a store that has multiple interfaces set up for auditioning.

for me a warm sound is more like the stereo compared to a simple mono'ish casette deck
i call it digital and cold, if it has less bass and treble and sounds flatter than usual
with less top end, while others will say it is a warmer sound when it has less top end
as you say,all is subjective to taste, ear and definition of sound.

Quite interesting what you tell about crosstalk and stereo width, what is less or more !
maybe you could talk a little about sound here, all basic what to know ?
to enlighten me so i know what i am looking for next time i want buy an Audio interface
and what is important to look and listen for.

FWIW, I had an Echo Layla 3G, which is supposed to be a solid, mid priced unit...which I replaced with a budget Steinberg UR44.  I couldn't hear any audible differences, although it wasn't able to do a quick A/B test.  Maybe they're both low enders and I haven't heard a great one yet....both monitored thru JBL and Yamaha speakers.  Also I've heard my stuff thru RME stuff and Focal TwinB's and didn't notice any improvement really either.  Maybe a difference??...maybe ...but not an improvement. 
I tend to think things like this are so slight nowadays and what goes into an audio card is much more important than what happens electronically.

The way i did test the two audio interfaces :

I have both installed with latest drivers, and outputs to my stereo amp.
* focusrite = Tape 1
* Ci1        = tape 2.

In windows control panel/sound, i right click " set as default device "
then quickly change from Tape 1 to Tape 2, on my stereo amp to monitor
the other then ill go back and forth in between them to compare.

I can use music ( reference ) from CD, or download wave files from internet
all audio that runs trough the computer can be used to compare in realtime.

mixmkr :
you say there's not that big difference, well maybe there's less difference in between
some Audio Interfaces, than others but in my comparison it was quite noticeable. 

So there is a difference, some less, some more and maybe some no audible difference.
Then there's difference between peoples ears to, some will hear a change and some do not.
by the way, all audio trough the whole chain has something to do with the overall final product
if i have 50 % bad gear with low end sound, it wont help me much if i use per $ 7k 
worth of EQ / compressor equipment, on the last 50% .

I will still have a " better " bad sound, but not 100% good.

It is the same with monitoring.... it wont help with Monitors priced $ 12k
when working in an untreated room with bad acoustics.

The question is :

* Is it better to buy and use a less " saturated " Audio interface while mixing
so i will mix more bass and treble in, and maybe widen it more.

* Or is it better to use a saturated Audio interface so i mix less in.

what is " better or worse " , not to mention :

what audio interface is closest in sound, compared to the " Pro Audio " mastering's out there
and give the most true / closest picture of the pro sound !

How can i tell this is better than this, compared to all the music out there...

The thought that comes to mind for me is (barring a bad recording) can't coloration differences between two decent interfaces be made pretty much identical with all of the mixing effects out there today?

I'd think the goal is to have the cleanest interface.  Not one that is warmer, etc.  Just the most accurate.
 
I won't disagree two interfaces can sound different, but I'd think the really low end products would be the most noticeable and ones that contrast.
I also tend to believe you get what you pay for...but nowadays the differences are much smaller and it costs A LOT more to get that final 2%.

Soundbend, I think the important thing to remember here is knowing what to expect from your system.
Everything lends some coloration to the sound, and you need to be aware of how what you hear in your studio translates to what others hear in their own environments.
If you know your equipment, "best" becomes somewhat moot.

Question's to all !

1. So what Audio Interface's do you use , and why ?

2. Did you have another audio interface before, and what was the main reason for the change ?

3. Did your mixes come out better, because of the Audio Interface, or because of new plugins ?

4. other ?

I don't think and have not heard a noticeable difference between similarly-priced units.  The software/latency sure, that is a function of skill, but as far as hardware design or quality of components and how they fit together - no.  The digital conversion chips are the same - there are only a few choices in a price range.  As far as the analog components getting the sound to and from the digital chips, there is only so much you can do.  You aren't putting in a $75 transformer in a $200 interface.  The other thing that makes a difference in sound (and not as big as transformer or less) is matching components by ear.  I know several guys that do that (Bryce at Warm Audio is a good example and Rupert Neve popularized hand tuning components back in the 60s - if $100,000 consoles are considered popular).  Craig talked about the same kind of investment of time put in by Tascam for the UH-7000.
 
The good news is that is all gravy.  The common everyday units put out by most companies are very good - good enough for pro work if needed.  There may be differences between X & Y, but it ain't even spitting difference.  Most of what people claim to be night and day are just good ole expectations.  You may hear a diff between a 5 year old unit and a cheap new one, but that difference is likely the same between any old unit and a modern one.
 
Where better components and design etc. make a difference is at the edges, esp. driving signals hard.  It is real, but you aren't going to notice much difference between $200 units.  Once you start spending 100s or a $1000 you can pay attention to the small but real advantages between units.  But for a entry level interface I'd be more concerned about latency and if the software works on my computer rather than about a sub .1 % difference in sound quality brought about by a different brand of capacitor used.  All the caps in each unit are based upon price not sound.
 
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