ACM & ACMP Reviews by Nuemes

  • Thread starter Thread starter nuemes
  • Start date Start date
OK, now the ACMP .wav doesn't contain any audio . . . :o . . . the .mp3 is OK, but I'd prefer to compare .wav to .wav :)
that's weird. it works on my machine :D (the two most often uttered statements of software developers) - but in this case, it really does work on my machine

edit: never mind :o -- give me a second...

OK - fished it out of a backup folder (computer had locked up) - I'm not sure the start and end positions are the same, but the information should be there now
 
Last edited:
Logical on first look, but AH stated that he has done much businiess with this manufacturer in the past (and into the future). QC is QC. Doesn't matter what the product is. Either the company is good about it or not. He seems to have found a way to work around it on the other products they make for him. No, he passed for other reasons altogether.

Which are? I don't know about judgment on Hyatt's saavy. He had the schematics. Was it saavy to run him off before he let on the real reason he passed on them (which admitted I don't know--I said "I bet")? We will likely never know now.

And I somehow gathered that the mics and pres are assembled in different locations. I could be wrong, but something Chance said a few months ago gave me that impression.

Anyway. The now-corrected samples are quite illustrative, I think. I will reserve comment, except to note that please, everyone, listen to the .wavs and not the .mp3s, because a hi-hat is exactly the sort of source with a lot of high-frequency energy that really gets screwed up with .mp3. I think that is equally true of both files, and it totally disguises the real difference between the preamps.

Second, the ACMP file needs to be bumped up by 3dB to match the level of the ART.

Finally, some people like to talk in terms of preamps being bright, dark, etc., as if preamps vary dramatically in frequency response, like microphones do. Generally, that is not the case at all; a preamp that doesn't test flat within the audible range would be considered quite colored, to say the least. So if you observe such behavior, you have to ask whether it is a nonlinear function of the preamp that is triggered by the source material.

I will say that due to the source material, I cannot make any judgment on noise. I can't quite make out the TV program in the background, either ;)
 
He had the schematics.

Yeah, which are - from everything I can tell - almost virtual rips of the originals that Rupert did 25+ years ago. Argue-ably the most revered pre's since the dawn of recorded time. What's not to like about that? Build quality, quality of components, QC, those are a different issue.

The pre's are built and assembled at the exact factory that AH uses for other products. Or so he said.

He was - as you say - "run off" due to his lack of social skills. Seems it wasn't the first time.

An ACMP would not be the pre I would reach for on a HH unless it was all I had.

In practical terms, pre's DO react quite differently to different mics. I find the ACMP's very weighty, large and (I hate to say it) "warm" sounding - especially compared to API's which are more forward and mid-agressive. Great for some things. Completely wrong for others. No one size fits all.

"Testing" is fine and good, and gives the potential user a glimpse of what the gear might sound like, but there is no substitute for putting your ears on it. And these pre's definitely have a "color". Some will like it, some may not.

My offer still stands to buy up any ACMP pre's that you guys don't want.....

PS - agreed about HH's and mp3's. Ick!
 
Hyatt's lack of social skills? That's funny. I don't think he called any group buy members "twats" :p

Bottom line is every fact Hyatt put forth in the thread has been shown to be true. He never said anything about defects, so we don't really know if he knew about them. But his pictures, schematics, and comments about origin of the design and transformers are all true.

The only "faux pas" Hyatt committed was talking openly about what was supposed to be "confidential". Well, everybody else in the group buy chose to use a thread in a public forum to discuss transaction details. What do you expect? I have never seen any of the transaction system used for the group buy, because I didn't buy anything! And yet, just by casually reading here, I know practically every detail of the group buy . . . big "secret", eh :rolleyes:

.
.
.

Back on topic, hey antichef, could I trouble you for one more comparison? Set the ART on low plate, and set the input gain such that the VU meter goes into the red (set on "tube") on hi-hat hits. Set the output gain to keep the peaks below -6dBFS. Compare that with the ACMP set as before.
 
In practical terms, pre's DO react quite differently to different mics. I find the ACMP's very weighty, large and (I hate to say it) "warm" sounding - especially compared to API's which are more forward and mid-agressive. Great for some things. Completely wrong for others. No one size fits all.

Strictly speaking, for mics and preamps to "react" differently, there has to be reactance . . . or complex source or load impedance. Are the ACMPs transformer input? I forget. Anyway, if you have a mic and a preamp with nearly pure resistive impedances, then don't really have any reaction between the mic and preamp, other than a bit of signal loss according to the source/load ratio. That's also essentially true if the mic has a reactive source impedance, but the input impedance of the preamp is high enough to negate such issues (kinda like damping factor for an amp, in reverse).

Now, if you have a mic with reactance and a preamp with reactance, or low enough source impedance to cause frequency-dependent loading of the mic, then you do have a system that will respond differently to changes in the mic/preamp combo.

That isn't too common in the lower-end world, mainly because inexpensive preamps tend not to use transformers. Most inexpensive condensers don't either; of course nearly all dynamics do. Most preamps are designed with sufficiently high input impedance to avoid loading mics in any case. Actually, I think the standard for preamps should be higher than it is--more like 3K instead of the more common 1K-1.5K. But that is an aside.

The ART is an interesting case, because it has a resistive load impedance which is variable. That essentially lets you choose whether or not you want the preamp to respond to the mic's reactance. Of course, if the mic is a resistive source, then you won't gain much other than losing signal level and possibly increasing distortion.

The SM81 does have an output transformer, I think . . .

Then there is the issue of what the preamp does with the signal, and some circuits may be more sympathetic to certain signals than others. But my point is, if you record a mic into an imaginary "straight wire", zero-gain, zero-noise preamp, then route that magic preamp into the preamp under test (where the magic preamp has zero source impedance), then the resulting signal should be the same as if you had plugged the mic into the preamp under test, even if the signals at the output of the magic preamp and the preamp under test are very different.
 
You're right Bill. I definitely get caught up in the discussion and I range from being really disappointed to very psyched without even hearing them. It's stupid of me.

I know you say that no pre is right for everything but what about all those amazing records we listen to in amazement that were recorded on in a room with one huge vintage console? Most anyone would take a vintage neve desk and nothing else if they had the option. Those pres seem to be fine for everything.

I know that these are not currently perfect, but with some good mods and the fact that these are very close to the original cicuit design of the neves, would it be safe to say that at some point they would be.

I'm sure the reasom why I obsess about the reports on these is that I made a substantial bet (for me anyway) on these and they are the heart of my studio. I will be using these for most everything. I have an 800r that I was planning on selling but now I think I need to hold onto for a clean pre option.

So my question to you is(since you are the one who I think has the most experience with these on a professional level), could you make a whole record with these and be happy like virtually anyone would with a real neve?

Thanks Bill.
 
An ACMP would not be the pre I would reach for on a HH unless it was all I had.
That's a good point, and a carelessly unspoken one from me -- I'm finding that I prefer the ACMPs for lower-frequency-dominant stuff like male vocals / bass, etc. -- I don't even have a kick drum :o -- I chose the hihat because it did a good job of illustrating one big difference between the 73 and the MPA. I can hear similar things going on with DI electric guitar. Now that we're narrowing in on high frequency with these, it'll be interesting to see how the performance/color compares to other Neve clones (and Neve's I suppose :)). DI bass would be a good complementary comparison to the hihats - and I can do that without sharing any TV shows (actually youtube or theonion.com -- TVs are so old school :D ).

It's also worth noting that the 73 is the only pre I have that can actually salvage my crappy voice -- I sang "sleigh ride" into it the other day, and got an eq-free keeper vocal track (which is a *first* for my voice).

My offer still stands to buy up any ACMP pre's that you guys don't want.....
Mine are *not for sale* :D


Back on topic, hey antichef, could I trouble you for one more comparison? Set the ART on low plate, and set the input gain such that the VU meter goes into the red (set on "tube") on hi-hat hits. Set the output gain to keep the peaks below -6dBFS. Compare that with the ACMP set as before.
OK - there may be some delay, as the wife and other kids returned from a visit to Grandma's shortly after the last test (and if you thought that one was noisy... :D) - and hitting a hihat late at night with a sleeping 2 year old might be frowned upon - unless I can do it tomorrow night and say we're leaving the drums out for Santa because he likes to play.... hmmm.... anyway, some time may pass, but I'll do it.
 
That's a good point, and a carelessly unspoken one from me -- I'm finding that I prefer the ACMPs for lower-frequency-dominant stuff like male vocals / bass, etc. -- I don't even have a kick drum :o -- I chose the hihat because it did a good job of illustrating one big difference between the 73 and the MPA. I can hear similar things going on with DI electric guitar. Now that we're narrowing in on high frequency with these

I don't think we are narrowing in on high frequencies, I think it's a bit more involved than that--there is a commonality among the sources people like, and also between the sources that people don't like.

Here, try this instead of testing hats on the ART again:

test_file.wav

Run that out of your converter, and first directly back into your converter, and record the result. That's just a baseline to determine how your converter performs.

Next, run the file out of your converter into the ACMP, with the input gain on its minimum setting, and the output gain on max. If that results in clipping, either the ACMP or your converters, turn down the test file in your DAW until the output doesn't clip the ACMP input. Shoot for the same -6dBFS level as you did with the hi-hat test.
 
Are the ACMPs transformer input? I forget.

The SM81 does have an output transformer, I think . . .

That's a lot of science for not even knowing anything about the gear you're talking about or having it in your hands to listen to. I use my ears. They are a resource I've developed over 25+ years in the biz. I don't dispute anything you said, but when it comes down to making decisions, the ears rule in my camp.....
 
I don't know about judgment on Hyatt's saavy. He had the schematics.

This I'm still confused about. Did Hyatt have the schematics of the Group Buy pre's? According to Chance these were designed by Chance's own tech:

2/1/08:
Nuemes: "Chance, can you describe the sound of the new rack gear or do some comparisons to existing preamps/comps that you've used?"

Chance: “Neve on the preamp.”
“Maybe I had better clairify something. They are not Neve clones. but are based on the 1073 design. My console is an Allen & Heath "Sigma" that was built for Cheap Trick with 24 of the 32 inputs having 1073 pre's built in. I have grown to love these pre's. As many of you know it has taken over a year to perfect these outboard pre's to the point that they are very close. I was so happy (and sad) when I took and returned them to the manufacturer (at NAMM) to let them know that we will go with this design.”


2/7/08:
Chance: I thought I mentioned this before, but maybe it's worth repeating. My console in my studio is an A & H Sigma, with 24 of the 32 inputs having 1073 pre amps built into the board. I have grown to love these preamps and with the help of the tech that services my board, took the design of these pres, and reworked and fitted the design into an existing enclosure. We sent it to China for their engineers to study. They built a prototype and sent it back to me. We tested it and made some changes and sent it back. they reproduced the changes and sent it back to me. We again tested it (my Neve tech did all of this) It sounded great (my test) we then approved the electronics and had them re package it into a compact enclosure and they brought the finished prototype, ready for production, to the NAMM show. Me and my tech forfitted going to the NAMM show on Friday to really go thru these 3 pieces of gear. We were so excited at the results, but reluctantly had to return them at the NAMM show on Saturday. The idea was mine, the circuit design was from a well known Neve tech here in LA. I paid him for his time and it was money well spent. We both never thought that these things would be this well made especially for prototypes"
 
You're right Bill. I definitely get caught up in the discussion and I range from being really disappointed to very psyched without even hearing them. It's stupid of me.

Not stupid, just shortsighted.

I know you say that no pre is right for everything but what about all those amazing records we listen to in amazement that were recorded on in a room with one huge vintage console? Most anyone would take a vintage neve desk and nothing else if they had the option. Those pres seem to be fine for everything.

Fine and great are two different things. It also depends on what you are recording. If I'm recording an orchestra, I would NOT opt for an 80 series Neve. If I'm recording a metal band, maybe. Those consoles are revered mostly because people have never had the chance to work on them and dream of doing it. Plain and simple. They don't have a clue.

Same with tape. It has reached near "God" status these days, and if I never use it again in my life, I will not shed a tear. I just went to a fellow GS studio to help him with his drum sound/setup. In his living room was a nice JH24. He's selling it after I told him before buying that if he didn't have the tech chops or a lot of $$, it would cause him more grief than it was worth. He found that out, and now it's for sale.

I wouldn't want to make a record with ONLY a U47. Neither would I want to make one with only a MXL mic. I'd rather go with the U47 though.....:D But given the preference, I'll take both!

Those old consoles are great, but the console didn't make the record. And even if you had the console beautifully restored at the cost of mega bucks sitting in your studio, without the room, the engineer, the producer and most importantly the musicians and the vibe of the 60's/70's draped over your studio, you'll be turning out the same stuff you do with your mackie board. It ain't the arrow, it's the indian.....

I know that these are not currently perfect, but with some good mods and the fact that these are very close to the original cicuit design of the neves, would it be safe to say that at some point they would be.

You're chasing phantoms.

It's been a couple of years since I worked on an 80 series desk. My memory has a HUGE problem retaining that "identical" sound for comparison years later. The real thing to be thinking about is not "do they sound identical, or can they be made to sound identical" to the 80 series pre/EQ's. The thing you should be thinking about is, do they sound acceptable, or better yet, do they actually sound GOOD. And in fact, they do. So even if the EQ thing never gets worked out, I'm as happy as a clam. Happier. They do things my API, Shadow Hills, Purple and D&R pre's can't and don't do. Simple. End of story. I could care less if they can be made to be identical in sound to a "vintage 84. Every one of those sounds different as they have all been maintained (or not maintained) in different states of care.

You WILL be happy. You'll have to trust me on that. And if you're not, I'll buy the unhappiness off of you. Don't forget, I'm first in line!!!!!! :D

I'm sure the reasom why I obsess about the reports on these is that I made a substantial bet (for me anyway) on these and they are the heart of my studio. I will be using these for most everything. I have an 800r that I was planning on selling but now I think I need to hold onto for a clean pre option.

As did we all. We threw the dice. They came up golden. Be happy. The waiting is the funnest part. Quit reading this inane threads, and look forward to the pre's. I'll bet you $50 that you will NOT sell a single one. Wanna take that bet in the spirit of anticipation????

I'm not familiar with an 800r. Don't know what it is, but if it's transformerless and clean and sounds good, then yes, I'd keep it. If not, budget for a nice clean pre. Some D&R's, Millenia, Massenburg, Forsell, etc.

So my question to you is(since you are the one who I think has the most experience with these on a professional level), could you make a whole record with these and be happy like virtually anyone would with a real neve?

Thanks Bill.

Probably, although I'm sure I'd be wanting other things as well if I couldn't use them. When it comes to Gear Aquisition, my expectations are getting lower the older I get. All this clamouring for gear is really just an excuse to not get out there and prove or - what many are fearing - DISPROVE your abilities. The reason those old guys used only Neve's or Trident's or Helios or ??? is because THAT'S ALL THEY HAD!!!!!!! If they had had alternatives, they most certainly would have put them to use. Sometimes your limitations and how you work around them are what define your "sound" or a certain project. Embrace it instead of trying to figure out how to buy more gear.....

I know, what a stupid idea on a gear forum......:cool:
 
This I'm still confused about. Did Hyatt have the schematics of the Group Buy pre's?

The only thing we know for sure is that SOMEONE is lying. Chance, Hyatt or the Chinese. I'll leave it to your own disgression as to who. I suggest you follow the trail of opportunity/money. In my experience, that generally leads to the REAL truth. Who was the most perturbed about the GB pre's? Who had the most to loose from the GB? Who had the most to gain?

You decide.

Reality is we'll never know......

It's a waste of time IMO. I have the pre's now and I'm happy.

I have made my decisions about who I WILL do business with in the future and who I will NOT do business with.
 
This I'm still confused about. Did Hyatt have the schematics of the Group Buy pre's? According to Chance these were designed by Chance's own tech:

2/1/08:
Nuemes: "Chance, can you describe the sound of the new rack gear or do some comparisons to existing preamps/comps that you've used?"

Chance: “Neve on the preamp.”
“Maybe I had better clairify something. They are not Neve clones. but are based on the 1073 design. My console is an Allen & Heath "Sigma" that was built for Cheap Trick with 24 of the 32 inputs having 1073 pre's built in. I have grown to love these pre's. As many of you know it has taken over a year to perfect these outboard pre's to the point that they are very close. I was so happy (and sad) when I took and returned them to the manufacturer (at NAMM) to let them know that we will go with this design.”


2/7/08:
Chance: I thought I mentioned this before, but maybe it's worth repeating. My console in my studio is an A & H Sigma, with 24 of the 32 inputs having 1073 pre amps built into the board. I have grown to love these preamps and with the help of the tech that services my board, took the design of these pres, and reworked and fitted the design into an existing enclosure. We sent it to China for their engineers to study. They built a prototype and sent it back to me. We tested it and made some changes and sent it back. they reproduced the changes and sent it back to me. We again tested it (my Neve tech did all of this) It sounded great (my test) we then approved the electronics and had them re package it into a compact enclosure and they brought the finished prototype, ready for production, to the NAMM show. Me and my tech forfitted going to the NAMM show on Friday to really go thru these 3 pieces of gear. We were so excited at the results, but reluctantly had to return them at the NAMM show on Saturday. The idea was mine, the circuit design was from a well known Neve tech here in LA. I paid him for his time and it was money well spent. We both never thought that these things would be this well made especially for prototypes"


Those comments, coming on top of a few other odd things back at the time, left me with doubts about their truth............sorry if my opinion offends, but there were some serious inconsistencies so it came as no surprise when AH revealed that these pres were already available from 797. The manufacturer was also experiencing difficulty with the EQ section back then ;)

:cool:
 
You WILL be happy. You'll have to trust me on that. And if you're not, I'll buy the unhappiness off of you.

Totally true. These are very good pre's for some things. Yes, the EQ is somewhat iffy and I'm not crazy about how it sounds when the gain is set high but you'll find good uses for the ACMP's amongst any current pre's you have. I'll be using them any time I record drums or bass.
 
The manufacturer was also experiencing difficulty with the EQ section back then

I didn't hear of that. Do you have quotes/dates from anyone regarding an EQ issue with the 727 units prior to the Group Buy units going out?
 
drBill, so happy you stepped in here. I am just a small home studio guy and my ACMP-73 and 84 sound great to me, but this is just a hobby for me, not a professional with the technical chops to go head to head with the pro's. I compared mine to the RNP, BG-1, and A-Designs P-1, pretty nice gear, and I love the pre's. Guess I am lucky, the EQ on mine work great also. The only flaw I have found so far is the gain for a soft voice with the SM7, but that is not a problem here, using LCD's and SCD's mostly, and when I use the SM7 on an amp, I just turn the volume up.
This thread was turning into a "told you so", but we, the buyers, are the winners. Thanks drBill for turning it around for us.
 
Back
Top