Topic: What makes a pre/adc sound good?

[poorlyconditioned]

I just listened to some recordings done into a NJB3 using *analog inputs* (elf power, 8/5/06, 40 Watt Club, Athens GA).

I realized that this doesn't sound very good.  It just sounds "flat".  I am not talking about the room or the PA (I don't think).  I know how those sound.  It just sounds like there is not crispness whatsoever.  It should be good, since he was using KM184 mics and a V2, but I guess the only thing to blame is the ADC, right?  So, what does something good sound like?  It soulds like a "veil has been lifted" is the best way I can describe it.  For example, a MD, while it sounds nice, one will see improvement with the UA5 instead.

So, what is it about the ADC and/or input stages that make something sound good?  I don't know.

Anyway, here is a summary of some setups I've tried, and what *I think* sounds good:
- NJB3 (sounds flat IMO)
- AD20 (sounds flat too, maybe a bit better than NJB3 though)
- MD (mic or line input.  sounds OK, better than NJB3 analog in, but not as good as UA5)
- UA5 (modded with AD8620 opamps, sounds better, more clarity)
- Presonus Firepox (best sound, *so far*, I have not tried new gear)

These are my own opinions.  But I do wonder when I see people running Neumann mics into a NJB3 or an IRiver!

 Richard

[aberg]

I just listened to some recordings done into a NJB3 using *analog inputs* (elf power, 8/5/06, 40 Watt Club, Athens GA).

I realized that this doesn't sound very good.  It just sounds "flat".  I am not talking about the room or the PA (I don't think).  I know how those sound.  It just sounds like there is not crispness whatsoever.  It should be good, since he was using KM184 mics and a V2, but I guess the only thing to blame is the ADC, right?  So, what does something good sound like?  It soulds like a "veil has been lifted" is the best way I can describe it.  For example, a MD, while it sounds nice, one will see improvement with the UA5 instead.

So, what is it about the ADC and/or input stages that make something sound good?  I don't know.

Anyway, here is a summary of some setups I've tried, and what *I think* sounds good:
- NJB3 (sounds flat IMO)
- AD20 (sounds flat too, maybe a bit better than NJB3 though)
- MD (mic or line input.  sounds OK, better than NJB3 analog in, but not as good as UA5)
- UA5 (modded with AD8620 opamps, sounds better, more clarity)
- Presonus Firepox (best sound, *so far*, I have not tried new gear)

These are my own opinions.  But I do wonder when I see people running Neumann mics into a NJB3 or an IRiver!

 Richard

I think those people running jb3's and irivers optical in should be fine as they are using external ADC's... but I definitely see what you're sayin'.

[BC]

So, what is it about the ADC and/or input stages that make something sound good?  I don't know.

From a measurements perspective, I would guess dynamic range, noise level, channel separation, and frequency response to start.

Dynamic range on the JB3 is probably not as good as on the other boxes?    

[mmmatt]

I just listened to some recordings done into a NJB3 using *analog inputs* (elf power, 8/5/06, 40 Watt Club, Athens GA).

I realized that this doesn't sound very good.  It just sounds "flat".  I am not talking about the room or the PA (I don't think).  I know how those sound.  It just sounds like there is not crispness whatsoever.  It should be good, since he was using KM184 mics and a V2, but I guess the only thing to blame is the ADC, right?  So, what does something good sound like?  It soulds like a "veil has been lifted" is the best way I can describe it.  For example, a MD, while it sounds nice, one will see improvement with the UA5 instead.

So, what is it about the ADC and/or input stages that make something sound good?  I don't know.

Anyway, here is a summary of some setups I've tried, and what *I think* sounds good:
- NJB3 (sounds flat IMO)
- AD20 (sounds flat too, maybe a bit better than NJB3 though)
- MD (mic or line input.  sounds OK, better than NJB3 analog in, but not as good as UA5)
- UA5 (modded with AD8620 opamps, sounds better, more clarity)
- Presonus Firepox (best sound, *so far*, I have not tried new gear)

These are my own opinions.  But I do wonder when I see people running Neumann mics into a NJB3 or an IRiver!

 Richard

I ran mbho > v2 > jb3 for awhile and I didn't think it sounded offensive... could have been better, but not as bad as I would have thought.  My rig prior was a mbho > USBPre > laptop and running the v2 > jb3 the next week in the same venue, config, band, and location I was stunned.  The USBPre, which a lot of people here like, sounded like complete ass as compared to the v2 > jb3.  It was like someone pulled a tarp off the HO's.  I also made quite a few recordings from my onyx mixer to analog in on the jb3 and thoes came out ok too.
     I think Brian Ska did a comp on the analog ins of the jb3 vs a d-10 and found little to no difference.  I'm betting you are hearing more issues than an inferior adc.

Matt

[poorlyconditioned]

So, what is it about the ADC and/or input stages that make something sound good?  I don't know.

From a measurements perspective, I would guess dynamic range, noise level, channel separation, and frequency response to start.

Dynamic range on the JB3 is probably not as good as on the other boxes?    

Yeah, this *should* be measureable.  There is no magic in audio, right!  I guess one should put a signal analyser in there somehow and measure distortion at all frequencies, and look for anomalies.  For preamps and ADC, this should be possible.  I imagine it is much harder with microphones.

  Richard

[Brian Skalinder]

I think Brian Ska did a comp on the analog ins of the jb3 vs a d-10 and found little to no difference.  I'm betting you are hearing more issues than an inferior adc.

I did the comp, yes.  Many people (but not necessarily me) found little to no difference between the two.

[MLKLuke]

how the R09 A/D could be positioned in that classification?

[RebelRebel]

I rate an ADC by invisibility......that is, I dont want to hear it at all.
preamps...well, that is a whole other can of worms.

Youll get a million different answers I suppose, because "good" is so hard to quantify..

[BC]

My rig prior was a mbho > USBPre > laptop and running the v2 > jb3 the next week in the same venue, config, band, and location I was stunned.  The USBPre, which a lot of people here like, sounded like complete ass as compared to the v2 > jb3.  It was like someone pulled a tarp off the HO's. 

Don't the MBHO's draw a lot of current in comparison to most other small diaphraghm conderser mics (besides Earthworks)?  I think I remember a chart over from Oade or DAT-heads that showed the HO's needed more mA's than your average mic.

That could have been a big reason your USBPre rig sounded poor, the USBPre had to draw all it's power from the laptop's USB, which might not have had sufficient juice to get the most out of the HO's. Just thinking out loud...

[mmmatt]

My rig prior was a mbho > USBPre > laptop and running the v2 > jb3 the next week in the same venue, config, band, and location I was stunned.  The USBPre, which a lot of people here like, sounded like complete ass as compared to the v2 > jb3.  It was like someone pulled a tarp off the HO's.

Don't the MBHO's draw a lot of current in comparison to most other small diaphraghm conderser mics (besides Earthworks)?  I think I remember a chart over from Oade or DAT-heads that showed the HO's needed more mA's than your average mic.

That could have been a big reason your USBPre rig sounded poor, the USBPre had to draw all it's power from the laptop's USB, which might not have had sufficient juice to get the most out of the HO's. Just thinking out loud...

maybe... The problem with high current draw reared it's ugly head with "motorboating" and this was not the case with the ho's.  I actually did get motorboating with my c-4's ((but not the c-1's) so I know what it sounds like.  the c-4 motorboating was because of an internal capacitor in the mic that the USBPre didn't like.  I ran the USBPre with all 3 sets of mics and none sounded very good... the c-4's didn't even work!  I found it so bad it was like a trasistor radio...  I even sent the unit back to SD and it checked out fine.

Matt

[it-goes-to-eleven]

  I ran the USBPre with all 3 sets of mics and none sounded very good... the c-4's didn't even work!  I found it so bad it was like a trasistor radio...  I even sent the unit back to SD and it checked out fine.

I ran into some issues when doing c4 > 722 testing. SP sent body schematics to SD.  The c4 mic output is not actually balanced (to lower costs). And for whatever reason SD's pre-amps don't seem to like it..  I haven't had any issues when running other unbalanced signals into the 722 (4061, RMod, nbox, etc).

[mmmatt]

  I ran the USBPre with all 3 sets of mics and none sounded very good... the c-4's didn't even work!  I found it so bad it was like a trasistor radio...  I even sent the unit back to SD and it checked out fine.

I ran into some issues when doing c4 > 722 testing. SP sent body schematics to SD.  The c4 mic output is not actually balanced (to lower costs). And for whatever reason SD's pre-amps don't seem to like it..  I haven't had any issues when running other unbalanced signals into the 722 (4061, RMod, nbox, etc).

I think it is just the c-4s though... at least for me the c-1's were fine.

Matt

[it-goes-to-eleven]

Drifting back to the topic at hand with some random thoughts on the subject..

I contend that a pre or A/D could have pretty lousy specs but still sound good and even better than a piece of gear that beats it on every spec.

As a quick example I would point to the specs for LP records.  They are quite limiting in every respect. Yet there is no doubt that within the range of those specs *very* pleasing sound can be acheived.

Obviously, the commonly evaluated specs are very important but I don't think they measure what makes or breaks "good sound".

I think "good sound" is very intangible.. The "I know it when I hear it" but cannot describe or quantify it.

Linn Audio had a marketing campaign where in evaluating audio systems they suggested the emphasis should be on whether a particular source/system was "toe tapping" and "musical".

One gotcha with that is seeing solo performers who are technically proficient, they can play the guitar really well and are working pretty hard at it, have decent lyrics, etc. Yet even during their live performance I don't find them that musical or toe tapping. And then there are those performers who manage to be 'off the scale' even when playing music that is very simple.. But I guess that goes back to garbage in, garbage out.

I think Richard started this thread with a focus on particular devices and trying to identify which are great. Then looking at the design/implementations in an effort to understand why.

One big difference in pre/AD combos is their ability to re-create an accurate 3D soundstage on good playback systems.  Are the players up front the correct distance from the players in back even when those back players are louder than anything else on stage?  What "specs" measure that ability?

One gotcha I see in evaluating A/D sections is good source material. It is tempting to compare A/Ds by using a CD as source material. I've done it before and was somewhat disappointed at how little difference I heard. And while I see some value in comparing how track x sounds when played into each piece of gear, in most cases that is a very limiting and compromised source.  A live analog signal has a tremendous amount of detail and gunk that the pre and A/D must contend with.

I haven't been doing much testing because it is summer.. But I've thought about setting up three or four windchimes in the basement in an effort to evaluate 3d soundstage accuracy..  Beyond the accuracy of windchimes in a quiet room, how is that accuracy maintained when there is a bunch of background noise?  Etc.