Topic: [Comp] V3 vs. DAV/BG1 vs. AERCO

[Church-Audio]

I did a quick test last night with a friend..  He noodled on his Gretsch hollow body electric 6-string, unplugged.  He hasn't played guitar much in the past few years and... nuff said.. Each 16/44 sample is a minute or two.


Mics were MG200 ORTF about 4-5 feet away.  Pre-amp gain 50 to 55 dB.  About 6 dB added in post.
Levels were tweaked to balance each sample at -17dB RMS avg.  The fireplace behind the mics can be heard popping.

mics > preamp > 722 @ 24/96 > Wavelab UV22HR

Cables were 1804a.  Preamps involved:  AERCO, DAV/BG1, V3.

The only way to do a test of two preamps with the same mics is to use a splitter.You split the signal into the front end of both preamps and into a 4 ch digital recorder, so that each pair can be evaluated. You can not evaluate two separate tracks with two separate preamps and deeside Witch one is better. The whole problem with doing the splitter is that a preamp is not expecting to see the load of a splitter, it wants to see the reactive load of a microphone thus the total performance of a preamp with non reactive load may impede the performance of the preamp in question. Even my method of splitting the signal is not great. But its better then two separate tracks with two preamps. The other huge problem is gain settings, you said you set the gains the same how do you know? you can not go by silk screening on a preamp, you need to send a known signal into the front end of the preamp. Use a 1k tone and measure the voltage of the output of each preamp to know for sure that they are indeed matched levels. If not the Fletcher Munson curve will make one seem better then the other, if there is level differences between the two preamp gain settings. Not to mention the fact that your using two different guitar tracks makes this test impossible to evaluate with no bias.


I hope that makes sense.

Chris Church

[RebelRebel]

I think he knows that chris...and this certainly was not a scientific test(if it were, the material would have been the same, among other things..)..but even still...the amp character stands out quite well. It was for fun, and it accomplished that goal...and life isnt made in a lab..there are variables. 

I did a quick test last night with a friend..  He noodled on his Gretsch hollow body electric 6-string, unplugged.  He hasn't played guitar much in the past few years and... nuff said.. Each 16/44 sample is a minute or two.


Mics were MG200 ORTF about 4-5 feet away.  Pre-amp gain 50 to 55 dB.  About 6 dB added in post.
Levels were tweaked to balance each sample at -17dB RMS avg.  The fireplace behind the mics can be heard popping.

mics > preamp > 722 @ 24/96 > Wavelab UV22HR

Cables were 1804a.  Preamps involved:  AERCO, DAV/BG1, V3.

The only way to do a test of two preamps with the same mics is to use a splitter.You split the signal into the front end of both preamps and into a 4 ch digital recorder, so that each pair can be evaluated. You can not evaluate two separate tracks with two separate preamps and deeside Witch one is better. The whole problem with doing the splitter is that a preamp is not expecting to see the load of a splitter, it wants to see the reactive load of a microphone thus the total performance of a preamp with non reactive load may impede the performance of the preamp in question. Even my method of splitting the signal is not great. But its better then two separate tracks with two preamps. The other huge problem is gain settings, you said you set the gains the same how do you know? you can not go by silk screening on a preamp, you need to send a known signal into the front end of the preamp. Use a 1k tone and measure the voltage of the output of each preamp to know for sure that they are indeed matched levels. If not the Fletcher Munson curve will make one seem better then the other, if there is level differences between the two preamp gain settings. Not to mention the fact that your using two different guitar tracks makes this test impossible to evaluate with no bias.


I hope that makes sense.

Chris Church

[Church-Audio]

I think he knows that chris...and this certainly was not a scientific test(if it were, the material would have been the same, among other things..)..but even still...the amp character stands out quite well. It was for fun, and it accomplished that goal...and life isnt made in a lab..there are variables. 

I did a quick test last night with a friend..  He noodled on his Gretsch hollow body electric 6-string, unplugged.  He hasn't played guitar much in the past few years and... nuff said.. Each 16/44 sample is a minute or two.


Mics were MG200 ORTF about 4-5 feet away.  Pre-amp gain 50 to 55 dB.  About 6 dB added in post.
Levels were tweaked to balance each sample at -17dB RMS avg.  The fireplace behind the mics can be heard popping.

mics > preamp > 722 @ 24/96 > Wavelab UV22HR

Cables were 1804a.  Preamps involved:  AERCO, DAV/BG1, V3.

The only way to do a test of two preamps with the same mics is to use a splitter.You split the signal into the front end of both preamps and into a 4 ch digital recorder, so that each pair can be evaluated. You can not evaluate two separate tracks with two separate preamps and deeside Witch one is better. The whole problem with doing the splitter is that a preamp is not expecting to see the load of a splitter, it wants to see the reactive load of a microphone thus the total performance of a preamp with non reactive load may impede the performance of the preamp in question. Even my method of splitting the signal is not great. But its better then two separate tracks with two preamps. The other huge problem is gain settings, you said you set the gains the same how do you know? you can not go by silk screening on a preamp, you need to send a known signal into the front end of the preamp. Use a 1k tone and measure the voltage of the output of each preamp to know for sure that they are indeed matched levels. If not the Fletcher Munson curve will make one seem better then the other, if there is level differences between the two preamp gain settings. Not to mention the fact that your using two different guitar tracks makes this test impossible to evaluate with no bias.


I hope that makes sense.

Chris Church

Life was so made in a lab 

[Church-Audio]

I hope no one misunderstands my post. I was not trying to say anything bad about this test. I was just simply saying that a real evaluation would need to be done with some kind of scientific method in order to get real results. That's it, I hope I did not offend anyone.

[it-goes-to-eleven]

The only way to do a test of two preamps with the same mics is to use a splitter.

First, this isn't a be all, end all comp.  I wish we'd get more comps like this on TS.. And especially more discussion of the comps and what we hear. So I do appreciate your feedback.

In all seriousness, I welcome someone to try and make C sound better than A or B on similar material

I have a splitter and have used it in the past.. But I don't feel comfortable trusting the comps. I'd have to do too much interaction testing to feel confident using it. So I'm shying away from it.

Also, I only have one 722 to use as an A/D.. So even if I had a magic splitter, I don't have the A/D for it.

But its better then two separate tracks with two preamps.

With a source this simple, even with the jumbled noodling, I disagree. Especially given that the alternative is a splitter.  The difference between A&B vs. C is dramatic.  A vs. B is a little tougher and really should be revisited.  I'm not so sure the B noise floor is higher.

I should have turned the furnace off for the comp.. The comp should have been done in the basement but we were getting ready to watch the world series..  Also, the TV should have been off but it was muted only 6' away.  I run the furnace blower constantly to circulate air and it is possible the furnace itself kicked on for B (raising that noise floor).

The other huge problem is gain settings, you said you set the gains the same how do you know? you can not go by silk screening on a preamp, you need to send a known signal into the front end of the preamp. Use a 1k tone and measure the voltage of the output of each preamp to know for sure that they are indeed matched levels.

I set the first pre levels based on the source, 55dB.  Then it was a no brainer to run the aerco at 50 because that's the max. I split the difference on the bg1 at 53.  In retrospect I suppose I should have run everything at 50 but I'm not sweating it because....

In post, I compared the rms and peak levels and adjusted them so the RMS levels were all matched at -17 dBFS. The peaks came out to within 0.85 dBFS.

If not the Fletcher Munson curve will make one seem better then the other

Those guys can kiss my sweet Aerco!

I hope that makes sense.

It surely does..

I have no doubt that this comp could have been done better but I am also pretty confident of the results. There has to be a balance between gettin'er'done and fussing over details..  I won't post a comp if I think it is unfair to a piece of gear or if I think the methodology was too sloppy.

[Church-Audio]

The only way to do a test of two preamps with the same mics is to use a splitter.

First, this isn't a be all, end all comp.  I wish we'd get more comps like this on TS.. And especially more discussion of the comps and what we hear. So I do appreciate your feedback.

In all seriousness, I welcome someone to try and make C sound better than A or B on similar material

I have a splitter and have used it in the past.. But I don't feel comfortable trusting the comps. I'd have to do too much interaction testing to feel confident using it. So I'm shying away from it.

Also, I only have one 722 to use as an A/D.. So even if I had a magic splitter, I don't have the A/D for it.

But its better then two separate tracks with two preamps.

With a source this simple, even with the jumbled noodling, I disagree. Especially given that the alternative is a splitter.  The difference between A&B vs. C is dramatic.  A vs. B is a little tougher and really should be revisited.  I'm not so sure the B noise floor is higher.

I should have turned the furnace off for the comp.. The comp should have been done in the basement but we were getting ready to watch the world series..  Also, the TV should have been off but it was muted only 6' away.  I run the furnace blower constantly to circulate air and it is possible the furnace itself kicked on for B (raising that noise floor).

The other huge problem is gain settings, you said you set the gains the same how do you know? you can not go by silk screening on a preamp, you need to send a known signal into the front end of the preamp. Use a 1k tone and measure the voltage of the output of each preamp to know for sure that they are indeed matched levels.

I set the first pre levels based on the source, 55dB.  Then it was a no brainer to run the aerco at 50 because that's the max. I split the difference on the bg1 at 53.  In retrospect I suppose I should have run everything at 50 but I'm not sweating it because....

In post, I compared the rms and peak levels and adjusted them so the RMS levels were all matched at -17 dBFS. The peaks came out to within 0.85 dBFS.

If not the Fletcher Munson curve will make one seem better then the other

Those guys can kiss my sweet Aerco!

I hope that makes sense.

It surely does..

I have no doubt that this comp could have been done better but I am also pretty confident of the results. There has to be a balance between gettin'er'done and fussing over details..  I won't post a comp if I think it is unfair to a piece of gear or if I think the methodology was too sloppy.

I guess the other problem I have is as a guitar player I can play two passages with the same notes and make them sound entirely different from a tone aspect simply by changing the way I play them so IMO it is very hard to tell with a solo instrument that can be changed just by applying more pressure or the angle of the pick to the sting. I am sure there is always better ways to do things I applaud you for taking the time to do this test. I am sorry for the misunderstanding. T+ For your efforts. I have not done any tests here at T.S so maybe I should just keep my mouth shut  I think its great that you have the time to do these tests and they are of value.




Chris Church

[Kyle]

We used our V2 between a sax mic (Audix D series) and a digital effects box when Dale and I were helping out a local band with sound last year.  We found the V2 to sound strident and edgy once the lights started to come on, which was at 25 dB.  It got noticeably worse at 30 db and pretty much trashed at 35 dB.  I don't think the Grace likes running at high gains.  That statement is probably true with most pre amps, but the Grace is not that, uh, Graceful, when it's wide open.  Interestingly, most of the mic pre's on our Allen and Heath GL2400 wound up between 15 and 20 db as well.  just some anecdotal evidence.

Chris

edit:  We thought the V2 did a great job once we found the right spot.  It was definitely not edgy.

I never liked running the V2 at high gain levels. It always began to sound compressed - maybe thin, or strident, or edgy (or all three) are better words, but I do not much care for it. FWIW - The manual says to run it at the lowest gain setting possible...

[it-goes-to-eleven]

FWIW - The manual says to run it at the lowest gain setting possible...

That sorta begs the question of what is the lowest optimal gain when you have a preamp that doesn't work so well at higher gain?

The v3 was 55db + 6dB in post.  How would 25dB + 35dB post, 35/25, 45/15 compare to that?

One comp I've been wanting to play around with is to record a clock ticking at 0 or 20dB gain from a distance and then boost the hell out of it in post.  I think that is also a good test of the A/D resolution (how does the r09 compare to the 722 with that input, etc).  It isn't music but it would tell a lot about noise floor, A/D res, and general detail. It is also fairly repeatable. I guess I need one of those guitar playing robots.


Another possible big difference in this comp is that the aerco output is unbalanced via rca. I used a 2 conductor teflon-silver cable with the shield tied to the ground at the aerco side only. How would it have sounded with the shield connected at both ends, etc? I have wondered whether an unbalanced output can compete with a good balanced output.

[it-goes-to-eleven]

Since there were no downloads today....

SPOILERS FOLLOW!!































a= DAV BG1
b= AERCO
c= V3

[Kyle]

In the past few years I have been running the V2 prety hot (balanced connection to ADC20 or AD2K) - but my old, uynbalanced rig (V2 -> SBM1) - I would run the V2 between 10db and 20db and have the SBM around 8 or 9 (depending on venue, location, etc).. Sounded nice without the noticeable 'artifacts' from higher gain settings. Example: at The Dead thing in 8/02 Apine, I ran V2 > ADC20, wit the V2 at +45 to get good levels. Levels peaked at 0, only 1 or 2 db attenuation needed on the pre, and easily one of the worst recordings I have made. Flat, no depth or dynamics, muffled sounding, unfocused....

I did run hot but did not clip....

Tried several different mic configs over the weekend and ended up with pretty much the same results....  always chalked it up to a too hot V2...

[F.O.Bean]

In the past few years I have been running the V2 prety hot (balanced connection to ADC20 or AD2K) - but my old, uynbalanced rig (V2 -> SBM1) - I would run the V2 between 10db and 20db and have the SBM around 8 or 9 (depending on venue, location, etc).. Sounded nice without the noticeable 'artifacts' from higher gain settings. Example: at The Dead thing in 8/02 Apine, I ran V2 > ADC20, wit the V2 at +45 to get good levels. Levels peaked at 0, only 1 or 2 db attenuation needed on the pre, and easily one of the worst recordings I have made. Flat, no depth or dynamics, muffled sounding, unfocused....

I did run hot but did not clip....

Tried several different mic configs over the weekend and ended up with pretty much the same results....  always chalked it up to a too hot V2...

ever think it could be mix

FWIW, after selling the v3 and getting the sax>722, i can def hear MORE noise-floor of this combo when testing batts and recording the tv/etc, compared to the v3. the v3 was quiet as a whistle and added no noise i could hear even at 60db gain, while having about the same gain now going sax>722 same distance from tv/config/etc, and i can hear tons more noise

BUT i dont plan on running the sax higher than 20db anyway, thats also the same gain i ran the v3 at going v3>xlr>722, max gain on v3 was 25 not edgy at all

now i did notice when cranking the v3 at too high a gain, it took it well, a little brittle in the high end sometimes but you had to run as near 0db or @0db so you had to crank the v3

kyle, i honestly think the brittle sound was the adc-20, those boxes can get ear-piercing high at times

where was your adc-20 gain at? was the adc-20 gain always at the same spots, emaning did you EVER tweak them or just adjust the v2?

[F.O.Bean]

also, the v2's trim pots are ATTENUATORS, they are NOT setup like the v3's trim at all, i would leave them open(at max gain) so you dont get that attenuator resistance going on, that can be heard sometimes i bet

[Kyle]

Bean
]
I did not like the sound of the ADC20 at all. But these recordings were something else entirely. I had the V2/ADC20 calibrated as per the SonicSense calpage, but I really had to push the V2 to get decent levels. The mix sounded good to my ears, and other recordings I have heard have been better. It could not just have been a hot V2, as I have run it hot before with somewhat similar (but not as extreme) results. Day one is ok, but day two is really awful. Almost unlistenable. It was a fun weekend though - maybe that had something do to with it

I just did a few comps of the 64s, Oade P2, PSP2, V2, and AD2K+ Analog in from the pre's to the p2, and then digi in from the ad2k (with both pre's). I need to flac 'em and get them posted. For the comps I used the Steely Dan Gaucho DVD-A, constant volume and gain levels, only changed the pre's and adc's. Mics were DINa. V2 @ 25db, PSP-2 @ min setting (around 22db I think). Recordings were 24/96.

V2 > P2 - detailed, but thin sounding, not much 'presence', slightly unfocused and distant.
PSP-2 >P2 - very rich, full sound, nice balance across spectrum, solid, tight bass, very detailed
It was very obvious which one was which.

Add in the ad2k:
V2 and PSP-2 were very simiilar sounding. You can tell the difference, and they are as described above, but much more subtle. Analog into the P2 - the differences jump right out at you. AD2K+  - I still prefer the PSP-2 but the V2 was a very close second. The AD2K is a really nice box at 24bit. Until tonight I have only run it at 16bit so this was quite an eye-opener.

I have to get out into the field to really put it through the paces. It sounds good, but so far the AD2K is the one to beat. More to follow...

I hope that makes some sense.  I'm gettin' tired  
 

[it-goes-to-eleven]

Analog into the P2 - the differences jump right out at you. AD2K+  - I still prefer the PSP-2 but the V2 was a very close second.

That is a curious result..  How did the psp2 > p2 compare to the psp2 > ad2k?

   

[it-goes-to-eleven]

now i did notice when cranking the v3 at too high a gain, it took it well, a little brittle in the high end sometimes but you had to run as near 0db or @0db so you had to crank the v3

Wait a minute.. Did you just say the V3 sounds spitty?