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API 1608 Mix Buss - Op Amp Blind Listening Test - API 2520, 990C, Rogue 5, GAR 2520, VF600, Red Dot
Old 23rd September 2020
  #1
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API 1608 Mix Buss - Op Amp Blind Listening Test - API 2520, 990C, Rogue 5, GAR 2520, VF600, Red Dot

Last night I did an op amp shootout for the mix buss of our API 1608 console. The test went as follows:

Merging Hapi D/A > line inputs on API 1608 > mix buss > Merging Hapi A/D

The test was done using ProTools @ 24/96 with the Hapi.

There are two source audio files:

1) "Holiday" by Madonna. 2001 Ted Jensen master. Up-res'd from 16/44.1 to 24/96 in ProTools.

2) "Toys" by Tyler Burns. (This is a section of a song I wrote...just the instrumental for this test...recorded at 24/96 on my Pacific Microsonics HDCD Model 2.)

The op amps involved in this test are, in no particular order:

Scott Lieber - Red Dot
API - 25250
John Hardy (Jensen) - 990C
Louder than Liftoff - Rogue 5
Inward Connections - VF600
GAR - 2520

We calibrated the output of the mix buss after installing each set of op amps in the 1608 center section.

In the folder below, I've also included the source files. (Please note that the source file for "Holiday" will be 6 dB louder than the op amp test files. I had to lower the volume of this master because the API 1608 doesn't have the headroom on the line inputs...)

Please cast your vote for your favorite and let us know what you think about each of the candidates! Link below:

Op Amp Blind Test
Old 23rd September 2020
  #2
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🎧 10 years
B,D,F is my pref for Toys, the others sound ever so slightly more clouded IMO.

Liked D most and B was okay and on Holiday.
Old 23rd September 2020
  #3
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I didn't care for A, B was ok. C was probably the warmest, most grounded, and D was similar but more open. E and F were the more transparent ones, with E being the widest, and F being similar but not quite as wide or bright but maybe a little more fancy. To my ears, D,E,F were the most transparent, though C also sounds good. I would probably go with E or F.
Old 23rd September 2020
  #4
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Prefered the originals in every case.


If comparing op amps alone, D and E stood out, but they seem louder than the others as well.
(D reminds of what a 4K SSL does and E is closer to what an APi would).

If gun to head...E.
Old 23rd September 2020 | Show parent
  #5
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Quote:
Originally Posted by thethrillfactor ➡️
Prefered the originals in every case.


If comparing op amps alone, D and E stood out, but they seem louder than the others as well.
(D reminds of what a 4K SSL does and E is closer to what an APi would).

If gun to head...E.
Well of course the originals are better...there aren't 2 levels of conversion, LOL.

E is definitely the "widest," whether or not that's the most desirable trait.
Old 23rd September 2020 | Show parent
  #6
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Quote:
Originally Posted by burns46824 ➡️
Well of course the originals are better...there aren't 2 levels of conversion, LOL.

E is definitely the "widest," whether or not that's the most desirable trait.
Its more solid in the center as well, which is what helps with the width.

For todays sound it works better IMO.
Old 24th September 2020
  #7
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D and E were my faves, with D getting the narrow victory. I didn't get scientific with it, just used iTunes which was a little clumsy. I'm interested to see the results.
Old 24th September 2020
  #8
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🎧 15 years
D E and F sounded better to me than A B C

E was the winner on Madonna

D was the winner for me on Toys

F sounded good except for a really weird thing happening up 15k and above. Just a bit squirrelly up there.
Old 24th September 2020
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This is really interesting to see people's opinions on this. I'll do some more listening and get back to you with my preferences before I post the key.
Old 24th September 2020
  #10
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My preferences are:

For "Holiday": B, then E

For "Toys": E, then B
Old 24th September 2020
  #11
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Preferred the sources in every case as well. I like the test though, at least this one has obvious differences.

For Holiday, remember, this is a done piece, it is presented originally as intended already, masterpiece, history maker, etc... So we all can really only speak on that. As far as Toys, that's your song, unfinished, so ANY of the choices are ok for that and opinionated due to the fact you could desire the said direction of "insert letter here".

So for Holiday if you like the most unchanged sound that doesn't degrade high end, , low end, shimmer, sheen and most importantly definition between bass and kicks, you have to go with D. Its simply the best, doesn't change the sound much, keeps definition and sheen. B being the worse as it changes the sound so drastically. Deadens it, dulls it and mushes the bass and kicks. E IMO is second best, as it does what D is doing, but it has slightly less bass definition. A brightens and brittle'izes the source too much. C is almost as bad as B but slightly less dead. And F is like C but not as bad. (bad meaning changing sound towards loss of sheen)

Most of the above is really not opinionated. Just fact. If you like to change the source then that's fine. Like I said, I don't like any of them. So I can speak from the viewpoint of what's changing the source the least and most and that's it. D is clear winner there.

Toys - Now this is subject to opinion. Cause if you want to dull out/soften your track a touch, B would be a excellent choice. Mix into it to so you compensate for its character. If you desire to brighten it, use A. If you desire a good solid keep it the same'ish sound go with D or E.

B is undeniably the most flat sounding depth wise. Loses that front to back massively IMO (on my monitors).

Now I will state opinion, I still like D the best for Toys too. D seems to me keep the depth of the sources the best. With E being a close second. A, B, C, & F all loose a depth character (at least on my monitors, lol). I think its rather obvious too. So great test ! Usually tests you can barely tell a difference. This was obvious.
Old 24th September 2020 | Show parent
  #12
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Quote:
Originally Posted by Infa ➡️
Preferred the sources in every case as well. I like the test though, at least this one has obvious differences.

For Holiday, remember, this is a done piece, it is presented originally as intended already, masterpiece, history maker, etc... So we all can really only speak on that. As far as Toys, that's your song, unfinished, so ANY of the choices are ok for that and opinionated due to the fact you could desire the said direction of "insert letter here".

So for Holiday if you like the most unchanged sound that doesn't degrade high end, , low end, shimmer, sheen and most importantly definition between bass and kicks, you have to go with D. Its simply the best, doesn't change the sound much, keeps definition and sheen. B being the worse as it changes the sound so drastically. Deadens it, dulls it and mushes the bass and kicks. E IMO is second best, as it does what D is doing, but it has slightly less bass definition. A brightens and brittle'izes the source too much. C is almost as bad as B but slightly less dead. And F is like C but not as bad. (bad meaning changing sound towards loss of sheen)

Most of the above is really not opinionated. Just fact. If you like to change the source then that's fine. Like I said, I don't like any of them. So I can speak from the viewpoint of what's changing the source the least and most and that's it. D is clear winner there.

Toys - Now this is subject to opinion. Cause if you want to dull out/soften your track a touch, B would be a excellent choice. Mix into it to so you compensate for its character. If you desire to brighten it, use A. If you desire a good solid keep it the same'ish sound go with D or E.

B is undeniably the most flat sounding depth wise. Loses that front to back massively IMO (on my monitors).

Now I will state opinion, I still like D the best for Toys too. D seems to me keep the depth of the sources the best. With E being a close second. A, B, C, & F all loose a depth character (at least on my monitors, lol). I think its rather obvious too. So great test ! Usually tests you can barely tell a difference. This was obvious.
Fascinating. D was not an option for me in this circumstance because it dulls the hi-end too much. It does have a pretty accurate representation of the audio, I suppose, otherwise, though! I found F to be hyped on both bottom and top so that the midrange gets a little squished.

All the differing opinions just go to show that the differences are very subtle! If you redid the entire console with a particular op amp, the differences would NOT be subtle, lol.

Again, yes, sources will always sound better...they lack two stages of conversion. Moot point. This is really about testing the accuracy and "vibe" of different op amps for a console center section, considering the source material.

Last edited by burns46824; 24th September 2020 at 11:44 PM..
Old 24th September 2020
  #13
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🎧 5 years
My headphone listening notes for "Holiday"...

A - Clogged/clumped, a bit lo-fi on high end. Kinda dead and boring. Not a fan. The keys that double the EP after the “bam!” in the intro sound crazy analog and wobbly, but possibly just standing out more in this one because of the lopsided presentation of the mix—on another check, this is not characteristic to the original recording, so it must be some sort of shifted-focus phenomenon because of how it distorts the mix. Cannot hear crosstalk at opening of muted cowbell in lower left headphone quite as clearly as in “D”. Inspires grey colors.

B - Fairly wide. More detail than “A”. A bit clogged/clumped, not very open or clear. A lot seems to be competing with the main vocal. Rather one dimensional, particularly evident when comparing the entry of the pad to it in “D”. Almost sounds “bit crushed.” Has a strangely interesting lo-fi analog wobble to it that is kind of cool. Makes me think of old Ariel Pink Haunted Graffiti stuff. Similar focus-shifting phenom to what was happening in “A”, putting the emphasis on EP and keys doubling EP. Can’t hear crosstalk at opening of muted cowbell in lower left headphone quite as well as “D”. Inspires a fair bit of ice-y, cold, winter colors—sounds like the mix is being defrosted.

C - Analog sounding bass and EP. Kinda cool, but not much replication in the highs on pad. Claps sound crunched and stuffy. Whole mix sounds squashed. Bass is out of control. Can’t hear crosstalk at opening of muted cowbell in lower left headphone quite as well as “D”. Inspires brown+grey colors.

D - Super wide [true wide, not that "wide" sound that comes at the sacrifice of squashing the north/south, frequency/pitch range, of the stereo spectrum (think of my impression of the Waltzing Bear ATR cards, compared to others, way back when..."D" is NOT like that)]. Spacious, three-dimensional, and clear. Stuff really really rings through the reverbs. Very nice separation between sounds. Sounds like you are "in the room", inside the reverbs. Bass feels in control compared to the others, more like original. Might be a tad hyped, but that could just be in comparison other Op-Amps tested here. Mix replication has the effect of enveloping—auditory equivalent to what an Omni-Max film projection does visually. Detail lost from the original recording sounds like what you might lose after a couple of analog duplications with identical machines. Joy to listen to. Feels like you are free to explore the stereo spectrum, free to walk around in there—which I can't say about any of the others, and which is my modus operandi for what a final mix should sound like if you want it to be relistenable throughout the ages—think Xiron cards I think this is the ticket.

E - Fairly spacious front to back. Scrappy detail on the high-end—compare tambo, pad, and clap high end to the precision on “D”. Everything is a little compressed and deadened. Bass is out of control. Aggressive. Inspires brown colors.

F - Pretty good. Sounds 70s. Decent mid detail, decent highs…but not as smooth and precise as “D”. Not very good reverb replication. Kind of flat overall from top to bottom (North/South). Out-of-control bass. Overall a little dead. Not much transient detail—listen to high notes of opening pad and compare to “D”. Inspires brown colors.

Will try to corroborate with "Toys" later if I can find time.
-Alec
Old 25th September 2020
  #14
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🎧 15 years
Having spent way too much time comparing op amps in a console summing bus (summing and following fader buffer op amp) here's my 2 cents:

1. There is not much point in sending through a stereo file. You need to create a mix and see how the mix bus changes the way EQ and compression works and how it influences your mixing decisions.

2. I had about half of the ones you had in your test plus 10 or so more 2520 footprint ones and many more monolytic IC op amps. Ultimately, there's just two op amps I liked on the mixbus:

For transparency the NE5534AN. It doesn't damage the integrity of the signal and sounds nice, full and natural without any obvious sonic signature. It's what I've got in my current ADT console. It makes much more sense to me to add a specific sonic imprint where and when you need it. You can get hybrid op amps with a 2520 op amp using an NE5534.

For punch, glue and fun mixing: The GAR1731. It ain't transparent, but it bends the signal in a way that makes it really easy to get a good sound going. There is some dirt added as a tradeoff though.

PS: I expected the 990C op amps to be great, but didn't like their sound on the mixbus. Wider bandwidth and lower distortion on paper didn't make them superior to the NE5534.
Old 25th September 2020 | Show parent
  #15
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Quote:
Originally Posted by living sounds ➡️
Having spent way too much time comparing op amps in a console summing bus (summing and following fader buffer op amp) here's my 2 cents:

1. There is not much point in sending through a stereo file. You need to create a mix and see how the mix bus changes the way EQ and compression works and how it influences your mixing decisions.

2. I had about half of the ones you had in your test plus 10 or so more 2520 footprint ones and many more monolytic IC op amps. Ultimately, there's just two op amps I liked on the mixbus:

For transparency the NE5534AN. It doesn't damage the integrity of the signal and sounds nice, full and natural without any obvious sonic signature. It's what I've got in my current ADT console. It makes much more sense to me to add a specific sonic imprint where and when you need it. You can get hybrid op amps with a 2520 op amp using an NE5534.

For punch, glue and fun mixing: The GAR1731. It ain't transparent, but it bends the signal in a way that makes it really easy to get a good sound going. There is some dirt added as a tradeoff though.

PS: I expected the 990C op amps to be great, but didn't like their sound on the mixbus. Wider bandwidth and lower distortion on paper didn't make them superior to the NE5534.
Very good point. This ain't a perfect test! Appreciate your recommendations as well. I didn't know about the NE5534AN...what other thoughts do you have on it?

I suppose we should note that the NE5534 is not discrete...
Old 25th September 2020 | Show parent
  #16
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Quote:
Originally Posted by burns46824 ➡️
Fascinating. D was not an option for me in this circumstance because it dulls the hi-end too much. It does have a pretty accurate representation of the audio, I suppose, otherwise, though! I found F to be hyped on both bottom and top so that the midrange gets a little squished.

All the differing opinions just go to show that the differences are very subtle! If you redid the entire console with a particular op amp, the differences would NOT be subtle, lol.

Again, yes, sources will always sound better...they lack two stages of conversion. Moot point. This is really about testing the accuracy and "vibe" of different op amps for a console center section, considering the source material.
This is indeed extremely fascinating. I'm actually blown away ! lol Like we all want the same thing - yet we are hearing it in different versions !

I am beginning to wonder if indeed monitors have a bigger impact on the differences we hear between us all ? But it shouldn't for things like "brighter, duller, etc.." Our listening positions have been calibrated, etc.. we should tell these differences similar.

For me, D kept all sheen. B was the dullest. A was the brightest (in a bad way). Its almost stark difference too. So this is why I am surprised at all our different remarks.

I mean for those that say "this is my favorite, this is not" I get that. They can say whatever and be 100% correct. But when we differ on saying which is less bright and more bright... dudes..haha, we got issues. Cause those things are not opinionated.

Focus on the hats and rhythm guitar in Holiday. No one else can hear how B sucks those things away compared to source, A brings them out (too far IMO) and D keeps them relatively the same the most.

Anyway- I can't wait to hear which is which now ! I vote D go in that board. Its the most transparent with still holding onto original depth. (somehow) I guess IMO though haha.
Old 25th September 2020
  #17
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In my test I didn't listen to the original source files. I was more after the differences between the sound of the op amps themselves. I also only listened to Holiday because I was in a hurry - but it was revealing enough to me. I'm staring at an API with 40some DOA's in it, so I'm real interested in the results.
Old 25th September 2020 | Show parent
  #18
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Quote:
Originally Posted by mark714 ➡️
In my test I didn't listen to the original source files. I was more after the differences between the sound of the op amps themselves.
You know years ago, I used to do that/think that too and then after long thought I realized without listening to source material, I have no idea what the said test results are truly yielding. I really don't even know the differences between them accurately because with no starting point reference, I don't know what each is doing in the first place to then gauge the differences between them themselves.

With a starting point raw foundation, you then know what each is doing to signal. Then comparing against each other has more meaning and weight to validity. Simply put, you don't know difference until you know beginning.

IE: I could say, omg, this one sounds very dark but full and solid. And this other one is perfectly sheened but a little light. And lets say you are a bright and light type of person you will say. I like this one because it has better sheen on top and that other one I don't like because it darkens up the mix. BUT if you listened to the source lets say the source was dark, full and solid iron type of sound.

This means the one that was dark, full and solid is not dark full and solid at all, it just passed on the info transparent like. The other one has a character that what you thought just keeps things bright, actually doesn't keep anything at all, it over brightens. So the descriptions used to describe each one was skewed due to not knowing source first. You buy it the one you thought you liked, and you're not happy. etc..

Point of which is truly better doesn't exist. The moral is, without listening to the source we have no idea what the differences are between them in all reality. Or should I better say, we have less of a idea than we think we do.

Quote:
Originally Posted by mark714 ➡️
I'm staring at an API with 40some DOA's in it, so I'm real interested in the results.
Wow ! Congrats ! I'll be rooting for ya to pull it off.
Old 25th September 2020 | Show parent
  #19
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Quote:
Originally Posted by Infa ➡️
You know years ago, I used to do that/think that too and then after long thought I realized without listening to source material, I have no idea what the said test results are truly yielding. I really don't even know the differences between them accurately because with no starting point reference, I don't know what each is doing in the first place to then gauge the differences between them themselves.
I don’t disagree, and I think you’re right. The level difference of the source material, coupled with my laziness to not import the files into a DAW made comparing the original sort of pointless. I’m listening through a bunch of 2520’s either way, so this test is particularly intriguing to me.

Maybe my ears are fried, but when I listened again tonight, “D” sounded a little more rolled off than I remember. Yesterday it was a pretty clear winner for me, with “E” close behind.
Old 25th September 2020 | Show parent
  #20
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Quote:
Originally Posted by burns46824 ➡️
Very good point. This ain't a perfect test! Appreciate your recommendations as well. I didn't know about the NE5534AN...what other thoughts do you have on it?

I suppose we should note that the NE5534 is not discrete...

Yes, it's not discrete, but a hybrid 2520 footprint op amp has output transistors to deliver the necessary drive capability.


Other thoughts... the 5532/5534 are responsible for much of the sound from the 80s onwards. Few releases have not travelled through those at least at some point. They've been ubiquitous in pro audio gear for decades. I have yet to find an op amp that I prefer sonically. In my ADT console even the transformer balanced preamps are based on it, and people have compared those preamps favourably to lot's of high end competition.

Last edited by living sounds; 26th September 2020 at 02:17 PM.. Reason: "decades", not "centuries". :-)
Old 25th September 2020
  #21
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Op Amp Key:

A - API 2520
B - John Hardy (Jensen) 990C
C - GAR 2520
D - Scott Lieber Red Dot
E - Louder than Liftoff Rogue 5
F - Inward Connections VF600
Old 25th September 2020 | Show parent
  #22
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5534

Quote:
Originally Posted by living sounds ➡️
Yes, it's not discrete, but a hybrid 2520 footprint op amp has output transistors to deliver the necessary drive capability.
..
Attached Thumbnails
API 1608 Mix Buss - Op Amp Blind Listening Test - API 2520, 990C, Rogue 5, GAR 2520, VF600, Red Dot-hybrid.jpg  
Old 25th September 2020 | Show parent
  #23
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Quote:
Originally Posted by mark714 ➡️
Maybe my ears are fried, but when I listened again tonight, “D” sounded a little more rolled off than I remember. Yesterday it was a pretty clear winner for me, with “E” close behind.
Oh man... the plot thickens !! lol Yea that has happened to me before. Just adds the classic confusion to me that this test already has ! haha I swear I will never be able to figure out hearing, ears, personal taste. Now lets add that little thing even scientists haven't 100% figured out yet and that's that little thing between our ears and the monitors called matter/ dark matter/atoms/ etc..

Fun fun fun !

BTW, that's exactly how I heard it ! D, then E. But I still hear it that way. Even blindly.
Old 25th September 2020 | Show parent
  #24
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Quote:
Originally Posted by burns46824 ➡️
Op Amp Key:

A - API 2520
B - John Hardy (Jensen) 990C
C - GAR 2520
D - Scott Lieber Red Dot
E - Louder than Liftoff Rogue 5
F - Inward Connections VF600
I have 2 VP 28's with gar 2520's. One is if the first run of VP28's the other a couple of years after and they each sound different. The original is thicker and the one after is clearer...go figure. Never liked running mixes or keys through them though.

Been meaning to tryout the Rogue 5 opamp in some Capi BT50's.
Old 25th September 2020 | Show parent
  #25
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Quote:
Originally Posted by burns46824 ➡️
Op Amp Key:

A - API 2520
B - John Hardy (Jensen) 990C
C - GAR 2520
D - Scott Lieber Red Dot
E - Louder than Liftoff Rogue 5
F - Inward Connections VF600
OMFG !

If I seen that list ahead of time, I would have said = F all the way. Followed by A.

Funny. A was by far the least mentioned here. WOW !

Thanks for this test. I now know what I'd get if I ever come across this situation.

I'm just so amazed how bad Inward Connections sounded *IMO* compared to how I feel about Steve's stuff.

Scott Lieber was D huh ? Wow. Good to know. Had a sound closest to source IMO.

So odd, API is notorious to warm things up a bit (so I thought). But from that test it was by far the complete opposite. A was the most brittle and hyped in the high end than any of the others (from my listening position anyway).
Old 25th September 2020 | Show parent
  #26
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Quote:
Originally Posted by Infa ➡️
I'm just so amazed how bad Inward Connections sounded *IMO* compared to how I feel about Steve's stuff.
I think the important thing to realize is that it's not bad, it's just got a different signature. Of course, one mixes "around" each of the different signatures. Having said that, yes, it did exaggerate the low end too much for my taste, although I've certainly used that op amp for mixing before!
Old 25th September 2020 | Show parent
  #27
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Quote:
Originally Posted by burns46824 ➡️
I think the important thing to realize is that it's not bad, it's just got a different signature. Of course, one mixes "around" each of the different signatures. Having said that, yes, it did exaggerate the low end too much for my taste, although I've certainly used that op amp for mixing before!
Very true. I used bad wording.

And that's the ultimate truth. If you mixed into any of these from the gate, you'd dial things the way you want so yea.. Moot

BUT, I said bad because this was for Mix Bus test right ? Mix bus = always running a full mix through it. These you want as transparent as possible (IMO). Some characteristics, even if cool to you personally, you wouldn't want permanently stamping itself into every single full mix etched in stone un-removable.

So let me reword, some of the others would be great to track a single audio source through to grab some character. But the most transparent one IMO is best *for a mix bus*.

None are bad here, no. But my personal preference is indeed some are bad for a *mix bus* scenario. F indeed added a hefty set of balls dangling. I love Steve's design and work. But maybe best as individual character flavor and not full mixes ?

F was far from the worse though (IMO).. so yea, Steve is still cool ! haha

Curious - were you able to pull this off blind testing for yourself ? Or due to being the host, did you know what you were listening to ? Also everyone hopefully included the laptop (extremely small) speaker test in their comparing ?. This reveals A LOT in certain other frequencies and most importantly is how 80% of your listeners will also be hearing the song/results.. so.. very important. After you do that, you then can make a well balanced decision of what is going on. Big speakers - small speakers. Combine results for good decision.
Old 25th September 2020 | Show parent
  #28
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Quote:
Originally Posted by Infa ➡️
Curious - were you able to pull this off blind testing for yourself ? Or due to being the host, did you know what you were listening to ? Also everyone hopefully included the laptop (extremely small) speaker test in their comparing ?. This reveals A LOT in certain other frequencies and most importantly is how 80% of your listeners will also be hearing the song/results.. so.. very important. After you do that, you then can make a well balanced decision of what is going on. Big speakers - small speakers. Combine results for good decision.
No, I was not able to do the blind test. However, I will say that I wasn't overly biased. I don't think I wanted any particular op amp to win. I suppose my biases would have been against the API 2520, as many people take them out, as well as against the SL 2520 "Red Dot," as this is generally seen to be more of an individual channel op amp and not so much of a mix buss op amp. Just admitting potential biases on my part. I bet the Blue Dots are very good, also, considering many people preferred the Red Dots in this test.

I have a feeling that I might, overall, chose E (Rogue 5) for my style of music (synth pop) because it is so wide sounding, whether or not that's from phase incoherence! Synth pop really benefits from the exaggerated width compared to rock.
Old 26th September 2020
  #29
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Interesting to look at the differences in these using some null testing software called Deltawave.

https://deltaw.org/

It aligns gain and timing within reason and subtracts one file from the other showing the difference. Like Diffmaker only it works without crashing has many more useful features and generally is 100 times better.

There are some idle tones at 27 khz and 42 khz not in the originals. This prevents getting a deep null of the recorded files vs the source file. However, you can usefully compare the recorded files to each other.

Frankly the remaining differences are so low I have my doubts anyone could reliably discern any two of these in an ABX test. Like using Foobar ABX a pair at at time. Deltawave also has an ABX comparator built into it. C has a very, very slightly rolled off treble which might be audible. A stretch I think. Remaining differences between the files are an A-wtd level of -80 db or less. Most of them are more like -90 db. The most different from the others is E which has a bit more treble roll off than C has.

Your mind will trick you to hear something different. And with the few responses something had to look like the better or worse. I'm not sure any of this is actually a big enough difference to hear. C and E with a bit of roll off would become a difference with multiple pass throughs. There appears to be nothing different in the lower frequencies of any of the recordings. No frequency response difference, no phase difference, just the same.

Thanks to the OP for going to the trouble to do this for us.

Last edited by esldude; 26th September 2020 at 09:02 AM..
Old 26th September 2020
  #30
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jjblair's Avatar
 
🎧 15 years
Interestingly, Firlotte designed the VF600 with color in mind, for single channel use, as opposed to the John Hall 690 that he uses for bus summing. Surprised you didn't use any 690s.
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