Hi,
I have compared MB2 with active and passive atc's. I thought the mb2 was better all around though classical lovers may prefer the atc's emphasis on the treble although it is a departure from neutrality. ATC can't play rock well. ATC were active or with Bryston. PMC used with Bryston. ATC are not TL - they have light bass.
Nick. |
Active ATCs are bass light - in the latest versions ATC deleiberately upped the bass balance to address this but they still dont have anywhere near the weight, extension or quality of pmc bass. Classical on atc is fine - but play rock and the treble is like fingers down a blackboard. I have heard them half a dozen times in different systems and the result is always the same. |
At different dealers over quite a few years. |
I use my PMC MB2's triamped - this is a big leap forward from monoblocks. According to PMC going fully active adds about another 5-10% performance in a treated room. I plan to convert to active using a custom crossover when the warranty runs out. |
I dont pay attention to stereophile - hifi mags (and dealers) are a thoroughly corrupt institution. Their recommendations reflect nothing more than their advertising revenue and the clout of the advertiser. The naim cdp and pre being a moot case. Naim are the most overrated amps in creation. They are just ripped off from 60s app notes in Electronics World and the like, without even the later design note amendments to remove the third harmonic which is now naims trademark (and marketed as a plus to add insult to injury!) Amps at 15% of the cost give the top naim pre power and cdp a sound thrashing. People buy B&W, naim, atc etc because the mags say they are the best. In general the more a mag hypes a product the worse it is - good products sell themselves. Just look at the underground following on the net now for hifi kit you wouldn't even know existed according to the mags.
The ATC's are bright and have light bass. Fine for classical but not for rock (many megadeath fans cant hear abouve 5 khz abyway ;-)). They sound nothing like real life tonally. A quck trip to an acoustic venue to listen to a real female voice will make that pretty clear. In two dems I went to woth two different friends both asked to be excused from the room while playing rock or female vocal on the atc 100A scm as it was too unpleasant to remain in the room (in an all atc system with naim cd player). They do not sound like real life and they were not designed to. They are near field studio mix monitors meant to pull the treble forward for analysis not enjoyment. I have heard the atcs recently and my comments still hold. |
Woo! You didnt need my help you started the fire burning all by yourself.
Yes Linn is surely the most overrated component of all time and the one most seriously past competition in the current market. Still marketing cost Linn less than having to R&D a new deck ... it would be the first one they actually designed after all. ;-) |
I have a feeling you two know each other ;-). I heard both speakers in exactly the same system dem - there is no issue of a "bad dem". It was a dealer dem with both speakers at the same time and was repeated accross several dealers. Your comments that I should have known that I was getting a bad dem but failed to perceive this are therefore pure supposition, incorrect and therefore irrelevent. I have had plenty of bad dems in the past and lots of dealer rhetoric and I know it instantly - you are doing it now. The self proclaimed "expert" trying to use his "expert" status instead of anything more substantial. ;-)
ATC are first and foremost a studio desk monitor company and that is what their products are designed for. Read their website. PMC are mastering suite monitors and that is something compeltely different. PMC are not a "copy" of ATC - they sound very different. I would suggest that repeated listening to megadeth at 110db+ has perhaps permanantly damaged your hearing if you cannot hear the difference ;-)! In terms of sound the atc has classic desk monitor balance while the PMC is much closer to the BBC sound.
The PMC has greatest advantage over the atc in the midrange, they orignally used the atc unit many years ago but switched to their own and this caused performance to leap forward, where it has remained. The extra "detail" of the atc is merely a treble boost relative to the PMC. Once that effect has worn off in perception then the PMC reveals it is more detailed and the treble is in better perspective.
You make a lot of baseless assumptions - "bad dems" or that I have not listened to the latest variants - in an attempt to undermine my remarks. Sorry but it won't work - stick to the facts. |
The ATC's are sharp and ATC are always having to mouth spiel about "accuracy" and "harsh recordings" to sell them. They are designed for mix analysis - that is where atc started and where they sold to the studios. That is their history and that is fact. Neither impulse response or IMD are relevent here you are just tossing in technical terms to try to make yourself look like an expert, hoping that I don't know what they mean and will back down. Unfortunately I understand them very well. The very fact that you have used terms that have no relevence prooves you are not an expert. Let's talk tweeter characteristics and crossover voicing. That is where the atc problem lies and they are voiced that way for a reason. It also explains why ATC have problems selling domestically in comparison to pmc who are the fastest growing audio company in the uk on the back of their domestic sales.
As I said in my previous emails throwing your baseless suppositions and trying to claim a position of superiority just doesnt work. It stands or falls by the facts and the listening experience. I didn't claim expert status - you did - so I don't have to defend myself as a "tourist". Incidentally I mentioned nothing about speaker placement (which influences the bass). However, PMC are a transmission design with a full bass and very effective room loading so benefit from free space siting. ATC have neither of these advantages so doubtless benefit from rear wall reinforcement. Which has nothing to do with the harshness of the atc anyway. As for the bbc sound the pmc owes a lot to that heritage and voicing - the designers were ex-bbc engineers and wanted to develop a full range design based on that ethos. Which they did - and forms the basis of my assertion.
I don't need a high frequency response plot to know a speaker is sharp if my ears are bleeding!
You are an atc dealer on audiogon. I seriously question your impartiality in this matter and beleive you are writing this for the benefit of potential customers that might be reading this. You must be aware I am not going to fall for it but plenty of audiophiles are pretty gullible and will fall for dealer rhetoric. I hope my response will make them think twice. |
No collusion - just human nature. People with vested interests are not impartial. Especially when it involves money. Hifi mags are corrupt - it has been proved in court in the UK. I also have friends "in the trade" and I am very well aware of what gopes on between dealers mags and the manufacturers. I am already on audio asylum - who is RGA? ;-) |
Sales training? This comment is rather revealing - so your spiel is "advanced sales training" then (advanced BS? ;-))? That would appear to be it in a nutshell. I dont work in hifi. However I do come from an engineering research background and my arguments are based upon that angle. Your suppositions are way off as always. As I said neither IMD or impulse response are relevent here. Had you made some more pertinent comments your assertions may have deserved more credulity.
Speaker performance isn't just about driver stats. Can you know a speakers bass extension just from the bass driver frequency range? Of course not. Same for the treble. The atc frequency response plots I have sign have a slight rise in anachoic conditions which equates to a treble peak in real life when reverbation in a real listening room is considered. +1db sine wave isnt much but +1db broad band signal is a lot of extra energy and the ear can pick it up easily. Again this cannot necessarily be deduced from the driver - the crossover and cabinet must be considered, as well as typical listening conditions. In addition frequency plots dont tell the whole story. Variations in off axis response can make any speaker look flat if you position the mic right - doesnt mean it reflects real life though. Lies, damn lies and statistics... and as these are musical reproduction devices the ultmate test of acceptibility is how they sound - in conjunction with rigourous enginerring development. I buy based on sound not stats (though I would like to imagine good engieering and good sound quality are strongly linked). However the latter on its own is not enough. Plenty of hifi has outstanding specs all round but still sounds awful. Because people develop to these metrics and our understanding is not complete. Plus manufacturers pick and choose specs to show their equipment in its best light and ignore the shortcomings so manufacturers specs are not a relaible source of information. This is true in every engineering field. There are opamps and transistors with fab specs but sound terrible - it's only when you examine them yourself that you see the short comings and they are not necessarily encapsulated by tradition specs. Music is a complex signal and it is very hard to make effective metrics - steady state sinewaves are not always useful - which is why lsitening tests are so essential. The ear is a nonlinear mechanism and the least well understood of our senses still. Psycho acoutics is still a bit of a black art.
In addition PMC midrange units are proprietary and the specs are not in the public domain (as you well know). The bottom line is - PMC sound markedly better on female voice. Partly due to TL and partly due to the improved midrange unit. If I was able to compare the specs of the two drivers I could perhaps suggest a reason for this. If you have them please forward them and I will be happy to do so.
To claim rear wall reinforcement will load a room as effectively as a TL is rather a bizarre staement at odds with scientific theory and practice. Back that up with a rigourous explanantion. I heard the ATC's close to the wall and also away from the wall. It was sharp either way. In addition TL stiffens the bass driver to give a double benefit. In combination these two effects not only improve the bass but have knock on effect into the midrange (which they partially cover anyway).
ATC have changed their story to match the changing times and the consumer market. They have already tweaked drive units and crossovers to make them more domestically acceptable in the treble and bass over the last few years. I have spoken to rec engs over the eyars and I know what they are used for. The sharpness is not a "flaw" when considered for the pro market. As I said the atc do what they are designed for - which doesnt align well with domestic use. Just because a spanner cant tithten screws doesnt mean it is flawed. Its a fit tool for its purpose and so is the atc. But now they want to make money from the home market. The adaptions they have already made prove my points.
As I recall I restricted myself to the products until you made groundless suppositions about the dems I have attended. In that light your remarks look pretty Clintonesque - accusing me of the very thging you are guilty in order to draw attention away from that fact. I dont say anything is wrong with the seas tweeter. I beleive the vociing of that unit in conjunction with the crossover is "wrong" and that has nothing to do with distortion specs at 3 khz. So you have a distortion versus frequency trace - so what? A little knowledge is a dangerous thing it seems. Look at the big picture. Not 0.1 db difference in distortion at 3 khz.
I am well aware you will sell both pmc and atc. I said you are baised about atc as you sell them I didnt say you were baised for atc over pmc ;-).
Yours is sales speil - good spiel but spiel nonetheless. Unquestioning acceptance of tech specs without really seeing the big picture or understanding R&D. Being able to quote tech specs and drop a few terms in doesnt equal understanding.
You ordered the "slam dunk" pizza - it just got delivered. I hope you like the free garlic bread. |
You are being a bit hard on yourself there - I think you gave equal account of yourself ;-) |
I agree - atc are too pricy and arent generalists in the same way as pmc |
Just because you say it came up short doesnt mean it did. You just stated that to be the case but provided no comments to back that assertion other than an irrelevent comment on rear wall reinforcement. Your response is just empty wind blowing. If it came up short then proove why.
There is no temperment of my earlier comments. They still stand unmodulated.
You have no idea how much R&D I have done thank you. More empty supposition on your behalf. You are a dealer therefore you are a salesman. If the conversation never got above elementary for you then show me the next level. You have failed to do so far. I await that respsonse with a high degree of anticipation.
"2pi" loading is not a scientific response to my arguments (most of which you have ingored as you have no answer). It is a simple statement of the loading effects of rear wall placement. My comments apply to sealed box as they do to ported designs. While sealed boxes do stiffen the mechanical resposnse of the bass unit they do not do so in as effective a manner as TL loading and also do not provide as effective bass performance. "acoustic impedance matching" - look it up. Anyway, as you may recall this discussion concerned the treble - not rear wall reinforcement. Do you have an answer for my rationale regarding anechoic measurement v in real room treble reponse given the observed treble lift? Nope not a word.
In summary empty bluster and a single irrelevent and inaccurate technical remark. And a lot of unsubstantiated "yo mama" waffle about how much higher your level is than mine.
The ball went through the hoop and its caught on camera - talk is cheap. You know more about speakers? Proove it. So far all your comments proove the opposite and I have given reasons to back my claims up. Try doing the same. I look forward to being educated. |
Hi. Another supposition! You assume I have a friend who knows about speakers - because otherwise your "story" about me just doesnt fit. Well sorry to have to tell you this but you are just plain wrong. I did this all alone and unassisted. What's more it was easy ;-). All you can do is make false assumptions and sling labels hoping they will fit as you have no technical argument to fall back on. All your suppositions are contradictory - you are just clutching at straws hoping something will stick. Consequently your remarks about my not coming out and saying what I have to say are so bizarre as to be inance beyond any hope of my making a sensible answer to such nonsense. I have clearly surpassed your presumptions about my level hence your need to invoke an imaginary speak expert who is whispering in my ear. Come on be serious. Do you think I am calling pmc or something?? I have no connection other than the speakers I bought.
I didn't temper my comments - if you read carefully I have not backed down on or moderated a single claim. If you beleive I have then show me which one.
As for my semantics they are perfectly sufficient and accurate though for truth I was dumbing down the concepts somewhat until you proved that you were taking things to a higher level. Please show me exactly where I was ducking in and out and I will be happy to clarify.
As for the atc measurements I have seen such on numerous occasions and you yourself admitted a treble peak of 1dB broadband!! Given that we both agree this fact then certain physical laws lead inexorably to my conclusion. You are hoist by your own petard. If I was fabricating "BS" then it's the same BS you also produced. I happen to know something about anechoic chambers as they were necessary for research work I did many years ago. No need for an imaginary expert - I have a research engineering phd and my own expertise is quite sufficient. Specifically I worked in speech recognition and monitoring systems - nothing to do with audio or sales but an area of engineering which distinctly overlaps in a lot of ways. A lot of use of anechoic chambers and frequency response measurements for speakers. So I know what reproduces human voice best and it is PMC not ATC - voices just don't sound the way the atc presents them tonally. Or do you still think I am a junior salesperson??? Given you have corroborated my assertion from your own mouth then surely the issue is beyond any contention.
People don't listen in anechoic chambers and the design should reflect this. The same as a speakers anachoic bass response does not match real world siting as you noted - so it is with the treble. ATC themselves rely upon rear wall reinforcement - this is a strengthening of lower bass response that would not be present in the anachoic measurement. However they factor it in for real world performance. That is just good engineeering practice and applies to the treble as much as the bass. No-one says you have to cut the treble but a reasonably directional tweeter and a flat response rather than a peaked response would be a good start. Got it? PMC are hardly dull sounding they are still brightish due to the FLAT response. In a treated room their inherent neutrality would be more apparent, just as it made the atc treble more palatable, though not quite neutral still due to the treble lift under anechoic conditions.
Sure you have to be careful with a TL - you need a big room I don't dispute that. I keep mine 2m from the rear wall and 1.5m from the side walls. Problem solved. Yes likely in a smaller room atc might sound better due to bass room interactions. However given a large enough room the TL will give much better results. Again I point you to the issue of acoutic impedance matching to the air mass - sealed or reflex boxes just can't compete. If you have technical papers that claim otherwise I will be happy to view them. In a large room with appropriate positioning the TL will give a flat response to an appropriate level and will do so more effectively in terms of dynamics and detail than a sealed box or reflex design. Which is exactly what I heard. There is no isssue of pmc ignoring room gain. You are off on a flight of fancy.
The issue here is the treble response not impulse response.
You claim to KNOW beyond any shadow of doubt quite a few things about me - many of which you have already abandoned as they proved to be wrong. You then move onto the next guess you absolutely KNOW is right. :S
"Voicing" is a non-technical description of interpreting test measurements in order to engineer a flat frequency resposnse taking into account room effects. Just a colloquial way of descrbing the R&D process. Happy now? ;-) I used these non-technical terms so as not to alienate other readers by trying too hard too look like an expert. Likewise with "sharp". Stop nitpicking it is irrelevent and petulant. We are not pretending to be hifi designers here. At least I am not ;-).
I suggest you read a techical book regarding TL, the theory is pretty clear - I have explained the issues but you don't seem to have grasped them. They are only boomy if poorly implemented or sited. It is very hard to make a good TL so usually sealed box or reflex is better implemented. However the failure is implemtantion not fundamental theory - and PMC have got it right. They provide a better match to the air mass of the room - that is established fact and the theory is outlined in even the most basic texts. The back pressure on the bass driver also improves control over the bass effectively as if it were increasing the damping factor of the driving amplifier. We can discuss amp design as well if you like - all my electronics is currently being converted to DIY kit - eventually only the speakers and turntable wil remain and I will convert the PMC to active using diy active crossovers and using my own in-room measurements. I am sure the atc crossover is very good - it is only the treble peak I take issue with. It's a preference not a flaw of the design. "Sharp" refers to a treble boost nothing to do with distortion. I think the PMC sounds cleaner myself but I think this is a knock on effect into the midrange of the TL driver.
The PMC midrange driver spec is not in the public doman so far as I know as it is an in-house design. contrary to your beleifs I don't have inside access at PMC. Nice try to trap me but no good I am afraid.
Your sub idea sounds good - it will doubtless work well when room size is limited. I have a huge listening area so I don't need to consider it. I have not observed any particular modal problems (except for one piece of organ music) so it isn't an issue for me. So long as you just use the sub low down and don't intefere with the mid then it's a good idea in principle.
I don't lump atc with B&W - atc are much better. I just don't like listening to either of them if the truth be told. I have no axe to grind why would I? You seem to think I have a vested interest but I do not. I found that atc and pmc sounded very different to me. Doubtless each excels in some areas relative to the others and maybe you prefer that designs compromises and I prefer PMC. They are designed for different things and their different tonal balance reflects that. For me tonal neutrality is the most improtant thing. I am certainly not dogmatic. I like bryston amps. However I prefer the older ST series - the SST range don't do much for me. So maybe they have sold out ;-). Maybe PMC will too. If soemthing better comes along I will happily buy it. If that happens to be ATC then all well and good. FYI most of my comments apply to the 100s.
By the way - which pmc models are you actualy talking about? My comments are restricted to the larger three way designs like the MB2. |
Haha thats ok, doubtless having a treated room makes the top end quite a bit more palatable. However this is something usually only studios or very dedicated individuals can commit to. I rent so it's not an option for me. Most rooms are very reverberent in the Uk due to wooden floors and even with carpets the treble just gets too strident especially with small rooms.
My first research job was working in speech recognition systems of which testing things like hearing and speaker systems is a very important part. One of the things I looked at was computer speech recognition in high noise and distortion environments like fighter cockpits. I then moved into RF engineering which also involved listening tests for radio intelligibility. I then went into nonlinear signals processing and analysis before jacking it all in to work in finance 5 years ago. My interest in diy just comes out of the fact I am interested in everything technical.
I have also rountinely had to have my hearing tested up to 20 KHz. My hearing extends flat past 16 kHz which is extremely unusual in a person of my age. I often find I can hear high pitched sounds that others can't and this is partially way high frequency treble boosts annoy me so much. To others they probably dont care. The person who complained the most when I took them to atc dems were female. They usually have better high frequency hearing too. She actually liked hifi (especially if it was big, bulky and black!) so she wasn't just petulant about being dragged in. ;-). She liekd the pmc best and I managed to convert her from cd to vynil in that dem (she thought there was soemthing wrong with the cd player initially!).
Are you using active crossovers with the atcs?
Nick. |
Ah well active and room eq makes all the difference - of course it can be as sharp or dull as you like then ;-) |
Admit it you loved it - why keep coming back to look else? Any other topics you want us to discuss? |
This is a hifi forum. I should perhaps have specified that it should be an audio related topic even if loosely connected. ;-) |
It sounds to me like the positioning was wrong. They need to be a long way from walls. As for the etching - people most often accuse this of the atc mid rather than the pmc. Still its all according to taste ;). The ib2 / mb2 also have the hand made mid which is quite a bit better than the vifa mid in the ib1. |
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