Philharmonic Audio - 3-way open back ML-TQWTs designed by Dennis Murphy

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Ricardojoa

Audioholic
Well, to be fair, the "inferior" part would really be due to the need to cross the Accuton at 2800 Hz, which is higher than it's crossed on the SoundScapes (because they use the wider RAAL ribbon element, which can be crossed lower). The Ne08 has better dispersion than the Accuton in the 2.8-3.0 k region.
Dennis, regarless of inferiority about the designs, would there be a tonal difference in the midrange between the BG and the accuton or maybe some scanspeak mid drivers, if as neutral as the design gets?
 
F

frsimms

Junior Audioholic
But, it's my experience that a good planar driver, if used within its intended operating range, is superior to conventional dynamic drivers. This is certainly the case for open-back operation, since the rear wave is unobstructed.
Maybe this will give you a clue. ;)

Bob
 
R

Ricardojoa

Audioholic
Maybe this will give you a clue. ;)

Bob
Well are u refering to me? I dont think thats what im looking for. I'm talking about tonal difference. Like for example, being warm or thin sounding. Scanspeak drivers seems to have a warm sound. So i was wondering about the accutton as the cone material can affect the sound. :)
 
GranteedEV

GranteedEV

Audioholic Ninja
Well are u refering to me? I dont think thats what im looking for. I'm talking about tonal difference. Like for example, being warm or thin sounding. Scanspeak drivers seems to have a warm sound. So i was wondering about the accutton as the cone material can affect the sound. :)
perceived "Tonality" from drivers is best described as a distortion.

what's creating distortion?

It could be the surround / suspension resonating.
It could be the motor.
It could be the cone material.

It's safe to say that the highest end drivers have very advanced motors with very low motor distortion. That rings true for Scanspeak, Accuton, Seas Excel, Audiotechnology, Acoustic Elegance, JBL, Faital Pro, B&C, Usher, etc.

So it boils down to the other two factors. The suspension resonances are often visible in frequency response graphs and good drivers will minimize their audibility. The crossover might be needed to reduce the audibility even further. It's not a DESIRABLE trait, it's just something that's there. Some people do like these effects though.

A lot of the reason people say "paper drivers sound warm and metal drivers sound hyped" is not because they sound that way, but because they're being driven out of their pistonic range. How high up is paper pistonic? I don't know - first of all there's a 100 different materials which fall into "paper" and second it's inherently a self damping material so it might not be pistonic but we might not notice its lack of pistonic behaviour in the response graphs. Unless you've got lasers to analyze what's going on, it's really anyone's guess. If you listen and hear "warmth" from a paper driver it's probably being crossed over higher than it is behaving pistonically - it's a distortion from cone breakup. Now paper cone breakup might not be offensive, but chances are it will smear details. Some people (IE Troels Graveson) actually prefer the less detailed sound for whatever reason. I'm pretty sure Dennis prefers unsmeared sound!

Now back to metal. Metal is a lot easier to understand. It's basically pistonic right up to its breakup. Its breakup is very strong and visible and it's also very offensive most of the time. Metal doesn't damp itself well so it needs a very careful crossover to work with. But in its passband you'll know exactly where it wants to be crossed. Whereas a paper driver might be forgiving enough to be crossed right over its broad breakup, metal wants you to push the breakup so low that not only is the breakup a good 24-40db down in level, but arguable so that the motor's 2nd or 3rd harmonic isn't exciting the metal resonance significantly enough.

The best kind of metal is probably beryllium, with a breakup mode like 3X higher than the typical materials. I'm no driver designer so I couldn't tell you the advantages of magnesium over aluminum or titanium, but if I had to guess, it has less to do with the breakup and more to do with stiffness vs weight (which affects sensitivity)

I think Ceramic is closer to what metal is...pistonic and then breaks up "ungracefuly" I'm not sure it has any real advantages over the magnesium in the excels... accuton just chooses to use it. The biggest advantage of the accuton over the excel drivers is just IMO (maybe i'm wrong) that it's physically smaller. I do know that harman has a Ceramic coated metal matrix driver material with a VERY high breakup.

Next come planars. I don't know a thing about them, but I'm guessing they give you that "pistonic" sound over a much wider bandwidth, because they're not piston drivers in the first place.

So would different drivers change the sound? Probably. But is that a desirable trait? I doubt it.
 
N

Nuance AH

Audioholic General
Well are u refering to me? I dont think thats what im looking for. I'm talking about tonal difference. Like for example, being warm or thin sounding. Scanspeak drivers seems to have a warm sound. So i was wondering about the accutton as the cone material can affect the sound. :)
I've heard two speakers with the Accuton mid (SoundScapes and the SS M7's); nether sound thin. They are warm, full and throw a very deep and wide soundstage. I really love their sound. Now if Dennis says the planar's are even better...well, I'm in love.:)
 
R

Ricardojoa

Audioholic
I've heard two speakers with the Accuton mid (SoundScapes and the SS M7's); nether sound thin. They are warm, full and throw a very deep and wide soundstage. I really love their sound. Now if Dennis says the planar's are even better...well, I'm in love.:)
Nuance,
after hearing the ST, i know that my next speaker, i want something a little warmer side. Dont get me wrong about the ST, they are very neutral and sound fabulous. But i have also heard some focus audio that sounded warm and i know now what people refer to romantic sound. It just sound so sexy and romantic with jazz and sexa. I would like Jim to build me a Floostander M7 but i would imagine it would be way out of my price range.

Nuance, why dont you spare some time and go audition the Phil?:D I really wanted your opinion on those as you heard the M7 and have the ST Ribbon, so im sure you can give an honest and unbiased review.
 
GranteedEV

GranteedEV

Audioholic Ninja
Woudnt that depends on the listener?
I don't see how. It's like saying some people like their TV screens with a big splash of blue tint all over it. There's only one source material, and the speaker should do the least to it as possible. Else why even bother with dennis murphy speakers. Sonus Faber is that way -->
 
S

Solid-State

Banned
The best kind of metal is probably beryllium, with a breakup mode like 3X higher than the typical materials. I'm no driver designer so I couldn't tell you the advantages of magnesium over aluminum or titanium, but if I had to guess, it has less to do with the breakup and more to do with stiffness vs weight (which affects sensitivity)
What do you think of the French Focal beryllium tweet? It's a very unusual inverse dome. BTW fantastic explanation about drivers and cone materials etc and the perceived affects of distortion.
 
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S

Solid-State

Banned
Nuance,
after hearing the ST, i know that my next speaker, i want something a little warmer side. Dont get me wrong about the ST, they are very neutral and sound fabulous. But i have also heard some focus audio that sounded warm and i know now what people refer to romantic sound. It just sound so sexy and romantic with jazz and sexa. I would like Jim to build me a Floostander M7 but i would imagine it would be way out of my price range.

Nuance, why dont you spare some time and go audition the Phil?:D I really wanted your opinion on those as you heard the M7 and have the ST Ribbon, so im sure you can give an honest and unbiased review.
uhh... I like FLAT speakers... If I need "warm" I'll use an EQ or I'll use Ozone plug. ;)
 
S

Solid-State

Banned
I've heard two speakers with the Accuton mid (SoundScapes and the SS M7's); nether sound thin. They are warm, full and throw a very deep and wide soundstage. I really love their sound. Now if Dennis says the planar's are even better...well, I'm in love.:)
I don't think so. It's all about economies of scale. Loudspeaker design involves tradeoffs when you can't have your own drivers wound/fab to specific electrical properties. The Neo 8 is about a $100 bucks a driver. The Accuton mid guys is like... what... $400-1000 a driver !?! Accuton make the most expensive drivers you can purchase for DIY. Will the Neo8 perform as well as a C90 or C173 probably not. But hey to add C173 for example would add $1000 to $2000 more to the price of the loudspeaker guys! The question isn't if it will be "better" it's will it be $2000 dollars a pair better!

To that I say NO WAY!

To give you guys an idea of the money you're talking about to design with Accuton take a look at this Madisound pricelist.

Madisound Accuton Price List
 
GranteedEV

GranteedEV

Audioholic Ninja
What do you think of the French Focal beryllium tweet? It's a very unusual inverse dome.
I've only heard it once, and my thoughts on it were "it sounds good". I'm sure it's a nice driver. I'm not sure there's any point in beryllium tweeters though, because the breakups tend to be above 20khz which is above the audible range.

I personally want beryllium only for one thing - compression drivers and maybe midranges but that would be very pricey. For 1" domes, I'm personally not sure any metal breakup would make a difference, although it will definitely affect sensitivity.

First thing you need to understand is that you can't compare individual drivers if the crossovers aren't similar. You're more likely to hear the crossover than the driver. So based on my Focal audition, I can't judge the driver. I can only judge the speaker as a whole.

Second you need to realize that unless you're comparing them at the same SPL level, the louder speaker will usually just plain sound better.

One speaker at 80db, and another at 85db, might not sound like a big deal but it can totally change our perception.

Third, you need to realize that rooms dominate a lot of what we hear. What sounds good in one room, might sound awful in another.
 
S

Solid-State

Banned
GranteedEV all kinds of fantastic points made! I hear ya about the tweet and only being able to hear the entire design. You have a very great understanding of loudspeaker design and obviously the science of audio as well. Do you work in the field/industry? I was considering moving to Calgary for work but I haven't seen a lot of "integrator"/"installer" work in the Calgary paper.
 
F

frsimms

Junior Audioholic
Nuance,
after hearing the ST, i know that my next speaker, i want something a little warmer side. Dont get me wrong about the ST, they are very neutral and sound fabulous. But i have also heard some focus audio that sounded warm and i know now what people refer to romantic sound. It just sound so sexy and romantic with jazz and sexa. I would like Jim to build me a Floostander M7 but i would imagine it would be way out of my price range.
Jim Salk and Dennis Murphy strive for transparency. They don’t design for warmth. As an example, the Philharmonic 2 can make you think you are sitting on stage with a symphony orchestra. The instruments have can have a palpable reality, roundness of tone and grit. That can be very thrilling, but is not what most would call warm.

Bob
 
S

Solid-State

Banned
....Which parameter are you talking about?
c173-6-090 Klippel Measurements

BG Neo 8 Specs

One look at the FR tells the story...

Truth is the Accuton drivers in terms of spec are in a class all to their own brother!

Just look at the FR on the usable band. It's no more that +- 2 dB from 200Hz to over 2000Hz for the C173-6-090
and third order HD hits at 5500. Through that entire usable band HD is no more than 0.5 dB

It's an INCREDIBLE driver!

Now take a look at the Neo8 specs...

Need I say more.

Remember people I'm comparing an $80 planar transducer to a $1000 mid range. More than TEN TIMES the price! To give you guys an idea of economies of scale. We are talking the price Denis is asking for one entire floor stander, assembled and tested in cab for the cost of JUST ONE Accuton midrange driver alone! The art of loudspeaker design involves compromise ok

The best performing use of a Neo8 is in a line array and is done again because of economies of scale. Imagine what an Accuton line array would cost!

PS Economies of scale means price decreases as unit production count increases... what is the inverse? because that's what I'm talking about...
 
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GranteedEV

GranteedEV

Audioholic Ninja
One look at the FR tells the story...
...Not one bit. Frequency response on a baffle changes entirely, and then again with the addition of a floor, and then many times again in a room. You also have to realize, is that after a crossover, response changes altogether. A driver like the Seas Excel W15 does NOT look flat but who cares, if it's going to be crossed over anyways?

You also have to consider how we hear.

We don't hear anechoic frequency response. What anechoic FR tells us, is freedom from resonances, and it has to have high resolution @ 1/12th octave otherwise it's a marketing graph.

When you put yourself in a room, you hear a careful combination of quick arriving response, but also reflected response.

The fact is, to get the same wide horizontal dispersion out of the 6.5" Accuton, that you're getting out of the narrow Neo 8, you need to cross the accuton over near 800-1khz (just guessing here). How many tweeters can play that low? Certainly not a ribbon, so now you've lost your awesome world class RAAL tweeter. And if you're crossing it that low, then what's the point of using ceramic? Why not use a paper driver and get some boost in sensitivity?

Okay, let's talk about the 4.5" accuton. It can play higher with similar horizontal dispersion, but still not as wide. You probably still want to cross it around 1.5khz or so. How many tweeters can play that low. Still not a RAAL 70-10D. Its big brother the 70-20D can play down to 1.8khz like the Salk Soundscape.

The crossover for the Philharmonics is near 2.8khz to the RAAL 70-10D (I swear the questions in this thread have made me analyze these speakers way more than any other speaker ever :eek: ) Either of the above accutons would, as Dennis stated, in FACT be inferior at this frequency. Just because they're flat, doesn't mean the sound being radiated into the ROOM and then reflected back, is nearly as balanced. The narrower than accuton vertical dispersion of the Neo8 may be beneficial as well at this frequency in many rooms, because the ceiling/floor reflections' intensity is reduced - and those are the strongest and earliest and offensive reflections!

Not to mention that for an open back design, having a giant motor behind the cone can't be great for even response exiting the back of the tube.

You can't look at the price of the accuton and make any conclusion. Make that conclusion with your ears, level matched, in the same room, with the appropriate crossover and preferably with a blind fold on to take away bias. Forget DIYers measured harmonic distortion too. Chances are it'll be masked by the audio content which has its own harmonic content. You can't normally compare world class drivers with harmonic distortion numbers... that's like comparing amplifiers with H.D. numbers.

there's parameters where the accuton is a more desirable driver. It's been discussed in this thread many times. The Neo8 won't mate to a 12" metal woofer. But it's not being mated to one. It's being mated to an 8" pulp woofer.
 
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S

Solid-State

Banned
I agree about Dennis's xover on this loudspeaker. Not only is it interesting in terms of the Raal xover point but also in terms of how low Dennis has that Neo8 running. It's 4LR point is 650Hz and seems really low for that planar. All this stuff is where the "magic" comes in right... I'd really like to see the xover. I'm curious if he had to pad the tweet to match Neo8 output etc. I'm also curious where the xover is physically located in the cab and if future access to it is possible. It's bloody obvious Dennis designed this speaker in many ways around the Neo8. I just hope his xover brilliance makes Neo8 the midrange so many have tried to make it.

The narrower than accuton vertical dispersion of the Neo8 may be beneficial as well at this frequency in many rooms, because the ceiling/floor reflections' intensity is reduced - and those are the strongest and earliest and offensive reflections!
This is the EXACT reason I'm looking at these speakers plus I do love Neo8 vocals and planar transducers for reasons partially sited in your above posts.

Even if the low Neo8 xover and my listening habits (loud rock) results in a new Neo8 every couple years I don't mind to get that planar mid sound. Heck I've seen deals at PE on them for as low as $70 a pop!

JUST WATCH YOUR IRON TEMP ON THOSE BLOODY PADS!
 
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GranteedEV

GranteedEV

Audioholic Ninja
I agree about Dennis's xover on this loudspeaker. Not only is it interesting in terms of the Raal xover point but also in terms of how low Dennis has that Neo8 running. It's 4LR point is 650Hz and seems really low for that planar.
Just FYI, the supplied manufacturer graphs are measurements of this planar are in dipole operation so there is a 6db/oct gradient rolloff before it even hits the 12db/octave natural driver rolloff.. This is a monopole speaker so the driver's measurements in a baffle will be notably different.

I'm curious if he had to pad the tweet to match Neo8 output etc.
Both the Neo8 and RAAL would likely have been padded. The woofer sets the sensitivity.
 
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