Active loudspeaker systems

[jtwrace]

I see.

[wisnon]

Thanks for the suggestion. But the requirement of my particular system is that all of the crossover DSP needs to be preformed in the digital domain.

 

It's going to be an extremely sophisticated system. I'm not going to share all the details on here but there's definitely nothing like it available on the market.

 

It's been 18 years in the works and there's far too many details to explain. I'll let the results of the finished product do the talking.

 

Isn't this what Goldmund does in their wireless active speaker system (though the Dac is limited to 24/96)? I know its scalable to 32 channels.

 

Here is an example: http://www.goldmund.com/en/products/logos_anatta

[Blizzard]

Isn't this what Goldmund does in their wireless active speaker system (though the Dac is limited to 24/96)? I know its scalable to 32 channels.

 

Here is an example: http://www.goldmund.com/en/products/logos_anatta

 

Similar concept. But not limited to 24/96. And not ugly.

[jtwrace]

Just to update your misinformation the NC1200 has NOT been discontinued.

[Blizzard]

Just to update your misinformation the NC1200 has NOT been discontinued.

 

 

I checked my emails and you may be right. What I was told is that's it's no longer available for new inquiries. So if you already have an established commercial amp that uses them, they are still available. I suppose if you wanted to order enough volume, they could produce anything you want.

[wisnon]

Similar concept. But not limited to 24/96. And not ugly.

 

Not class D power either (ultra-wide bandwidth Job circuit), Leonardo software time aligned and Proteus software is class leading, IMHO.

 

I will take plain Jane looks for all that. LoL

[Blizzard]

Not class D power either (ultra-wide bandwidth Job circuit), Leonardo software time aligned and Proteus software is class leading, IMHO.

 

I will take plain Jane looks for all that. LoL

 

There's nothing wrong with the Ncore class D amps. They are pretty much the perfect amplifier. I'll put a 2 channel version of my amps up against $20000+ class A/AB amps all day long. And in my system each driver gets one of them.

 

The software I'll be using is state of the art. Along with the real time operating system it runs on. Impossible to achieve this level of quality on DSP chips. And Definitely no DSD 512. This is a cost no object project. So I'm using the best of everything.

[jtwrace]

I checked my emails and you may be right. What I was told is that's it's no longer available for new inquiries. So if you already have an established commercial amp that uses them, they are still available. I suppose if you wanted to order enough volume, they could produce anything you want.

 

I know I'm right as I was able to confirm with Hypex.

[Blizzard]

I know I'm right as I was able to confirm with Hypex.

 

It's not a better amp module anyways. Just more powerful. The reason it was priced higher is because at the time of its release they didn't have their new high efficiency factory building them.

[wisnon]

There's nothing wrong with the Ncore class D amps. They are pretty much the perfect amplifier. I'll put a 2 channel version of my amps up against $20000+ class A/AB amps all day long. And in my system each driver gets one of them.

 

The software I'll be using is state of the art. Along with the real time operating system it runs on. Impossible to achieve this level of quality on DSP chips. And Definitely no DSD 512. This is a cost no object project. So I'm using the best of everything.

 

The software I speak of runs on mainframe and built by egghead PHDs plucked from University after they did dissertations on this stuff. This is exteme professional grade stuff that drive all Goldmund speaker designs and have major collaboration from Univ and industry collaboration. They have the $$$ to fund this.

 

I will take the Telos amps over any N-Core, and this is no diss to the N-Core, but the Telos circuitry has been refined for 30 years with deep pockets…and yes, the Prologos has 2 amps per box. The Anatta is even more outrageous and is priced outrageously too:

 

Goldmund - Logos Anatta

 

They are bad to the bone…

 

I imgine your stuff will represent FAR better value for price paid though.

 

Marketing blurb here:

The primary objective of the Proteus project was to develop a technology that would allow us to make the most perfect speaker on earth.

This took the company 7 years of painstaking research and development efforts and resulted in the creation of the Epilogue 1 Signature. Our acoustic laboratory was prompt to discover that Proteus could also be applied to many other speakers (even those manufactured by other brands), optimizing their performance.

 

I know from 6moons article that this will be applied to Kaiser speakers.

[jtwrace]

It's not a better amp module anyways. Just more powerful. The reason it was priced higher is because at the time of its release they didn't have their new high efficiency factory building them.

 

I didn't say it was better or not....this is about you saying it was discontinued.

[Blizzard]

The software I speak of runs on mainframe and built by egghead PHDs plucked from University after they did dissertations on this stuff. This is exteme professional grade stuff that drive all Goldmund speaker designs and have major collaboration from Univ and industry collaboration. They have the $$$ to fund this.

 

I will take the Telos amps over any N-Core, and this is no diss to the N-Core, but the Telos circuitry has been refined for 30 years with deep pockets…and yes, the Prologos has 2 amps per box. The Anatta is even more outrageous and is priced outrageously too:

 

Goldmund - Logos Anatta

 

They are bad to the bone…

 

I imgine your stuff will represent FAR better value for price paid though.

 

Marketing blurb here:

The primary objective of the Proteus project was to develop a technology that would allow us to make the most perfect speaker on earth.

This took the company 7 years of painstaking research and development efforts and resulted in the creation of the Epilogue 1 Signature. Our acoustic laboratory was prompt to discover that Proteus could also be applied to many other speakers (even those manufactured by other brands), optimizing their performance.

 

I know from 6moons article that this will be applied to Kaiser speakers.

 

Sounds pretty cool. But unfortunately some people would never buy them based on appearance alone. And also a shame to not be compatible with DSD, and any PCM over 24/96 will need to be downsampled.

[Blizzard]

I didn't say it was better or not....this is about you saying it was discontinued.

 

Well discontinued for anyone who doesn't already have an established commercial design using them.

[jtwrace]

Well discontinued for anyone who doesn't already have an established commercial design using them.

 

That's not true either.

[wisnon]

Sounds pretty cool. But unfortunately some people would never buy them based on appearance alone. And also a shame to not be compatible with DSD, and any PCM over 24/96 will need to be downsampled.

Cosmetic designs will change next year. they are sponsoring a design competition with big $$$, so…

 

And speaker design cycles are pretty quick, that's why they could create 10 new speaker models in 2014 alone.

 

In audio more than any other domain, time is of the essence. A proper time alignment is crucial in what we call the Recognition Factor, which is the ability of our brain to recognize a sound as real (high recognition factor) vs. reproduced (low recognition factor).

The time alignment technology used in Proteus is called the Leonardo Time Correction. In a system that does not use time correction the listener’s brain concentrates on reconstructing the time alignment of a sound that it perceives as un-natural (time distortion does not exist in nature).

In a system that includes a Leonardo configuration, this action is performed by the audio system itself, leaving the brain focus on the music itself and on the true emotion that a completely natural sound brings to each passionate music listener.

A Leonardo configuration is a digital file used by the Goldmund processor. The file’s parameters are calculated based on the speaker’s technical specifications. All recent Goldmund speakers function with Leonardo configurations as part of the Proteus technology.

 

E. The Proteus Speaker Modeling Software: The Total Correction

During the last 10 years, one of Goldmund’s greatest achievements has been the creation of Proteus, its Mathematical Modeling Software capable not only of designing perfect speakers out of any enclosure shape but also of integrating the results in a room, even for multi-channel. Some traditional audiophile speakers may be assembled with the best drivers in the best enclosure, without sounding lifelike at all. Most of the problems are with the crossover and the low frequency tuning. If properly designed, the crossover is supposed to avoid major amplitude accidents in the speaker frequency response. Some may even achieve a decent phase response with acrobatic passive crossover design (detrimental to the “Acoustical Grounding” anyhow as we have seen before). But the major distortion created by the crossover remains the time distortion and this cannot be corrected in a passive crossover. It requires working in the digital domain, with access to mathematical modeling software. Thanks to Proteus, and thanks to the digital DSP crossover used in all the Goldmund Standalone Speakers, all forms of distortion can be systematically eliminated. Using “Leonardo”, a method developed especially by Goldmund, the Time distortion can be neutralized. But also, both amplitude and phase response accidents of the global speaker, usually due to its shape, its port tuning etc... can be corrected with an extreme precision.

The Result: For the first time, a speaker totally corrected in amplitude, phase and time can be produced. The audible effect is staggering of vividness, and the recognition factor highly improved (this factor concerns the ability of the brain to recognize a sound as real vs. reproduced. It is highly influenced by the alignment of frequencies that, in nature, reach your ear at the same time but that are not properly aligned when any sound is reproduced). In addition, thanks to Proteus, more elaborate shape or different construction can be introduced, the final result being maintained unchanged.

F. Additional Possibilities: The Tuning Of The Room

Tuning the acoustic response of a room is a necessity in many home installations. Often installed in a living room, the system acoustics are far from perfect. Achieving some corrections with acoustic materials or accessories remains possible but then forget the “Wife Acceptance”. With the Goldmund Standalone Speaker, an internal powerful DSP circuit is integrated in the speaker, providing many possibilities of correction that can be calculated by Proteus.

The Result: A perfect system in a perfect room was something requesting extreme acoustical treatment and remaining imperfect. By using Proteus and a Goldmund Standalone Speaker, it is now possible to install it without major constraints for your décor choices. Mixing hidden and visible speakers also provides the possibility to achieve good-looking multi-channel systems for film or concert in a living room.

[Blizzard]

That's not true either.

 

Well that's what they told me. Unless they changed their minds since April. Either way I'd choose the better spec 500. 700w into 4 ohms is enough for each of my drivers. Hard to beat the 135db S/N ratio as well.

[Blizzard]

Cosmetic designs will change next year. they are sponsoring a design competition with big $$$, so…

 

And speaker design cycles are pretty quick, that's why they could create 10 new speaker models in 2014 alone.

 

In audio more than any other domain, time is of the essence. A proper time alignment is crucial in what we call the Recognition Factor, which is the ability of our brain to recognize a sound as real (high recognition factor) vs. reproduced (low recognition factor).

The time alignment technology used in Proteus is called the Leonardo Time Correction. In a system that does not use time correction the listener’s brain concentrates on reconstructing the time alignment of a sound that it perceives as un-natural (time distortion does not exist in nature).

In a system that includes a Leonardo configuration, this action is performed by the audio system itself, leaving the brain focus on the music itself and on the true emotion that a completely natural sound brings to each passionate music listener.

A Leonardo configuration is a digital file used by the Goldmund processor. The file’s parameters are calculated based on the speaker’s technical specifications. All recent Goldmund speakers function with Leonardo configurations as part of the Proteus technology.

 

E. The Proteus Speaker Modeling Software: The Total Correction

During the last 10 years, one of Goldmund’s greatest achievements has been the creation of Proteus, its Mathematical Modeling Software capable not only of designing perfect speakers out of any enclosure shape but also of integrating the results in a room, even for multi-channel. Some traditional audiophile speakers may be assembled with the best drivers in the best enclosure, without sounding lifelike at all. Most of the problems are with the crossover and the low frequency tuning. If properly designed, the crossover is supposed to avoid major amplitude accidents in the speaker frequency response. Some may even achieve a decent phase response with acrobatic passive crossover design (detrimental to the “Acoustical Grounding” anyhow as we have seen before). But the major distortion created by the crossover remains the time distortion and this cannot be corrected in a passive crossover. It requires working in the digital domain, with access to mathematical modeling software. Thanks to Proteus, and thanks to the digital DSP crossover used in all the Goldmund Standalone Speakers, all forms of distortion can be systematically eliminated. Using “Leonardo”, a method developed especially by Goldmund, the Time distortion can be neutralized. But also, both amplitude and phase response accidents of the global speaker, usually due to its shape, its port tuning etc... can be corrected with an extreme precision.

The Result: For the first time, a speaker totally corrected in amplitude, phase and time can be produced. The audible effect is staggering of vividness, and the recognition factor highly improved (this factor concerns the ability of the brain to recognize a sound as real vs. reproduced. It is highly influenced by the alignment of frequencies that, in nature, reach your ear at the same time but that are not properly aligned when any sound is reproduced). In addition, thanks to Proteus, more elaborate shape or different construction can be introduced, the final result being maintained unchanged.

F. Additional Possibilities: The Tuning Of The Room

Tuning the acoustic response of a room is a necessity in many home installations. Often installed in a living room, the system acoustics are far from perfect. Achieving some corrections with acoustic materials or accessories remains possible but then forget the “Wife Acceptance”. With the Goldmund Standalone Speaker, an internal powerful DSP circuit is integrated in the speaker, providing many possibilities of correction that can be calculated by Proteus.

The Result: A perfect system in a perfect room was something requesting extreme acoustical treatment and remaining imperfect. By using Proteus and a Goldmund Standalone Speaker, it is now possible to install it without major constraints for your décor choices. Mixing hidden and visible speakers also provides the possibility to achieve good-looking multi-channel systems for film or concert in a living room.

 

Yeah I can imagine they are pretty good. Better be for the price.

[jtwrace]

Well that's what they told me. Unless they changed their minds since April. Either way I'd choose the better spec 500. 700w into 4 ohms is enough for each of my drivers. Hard to beat the 135db S/N ratio as well.

 

You might want to look closer on them both...

[Blizzard]

You might want to look closer on them both...

 

I'm not much of a fan of the IC opamp input stage on the NC1200. I tried the same with the NC500. Absolutely no comparison to my pure class A discrete input stage.

[XP9433]

The MTM approach was developed to overcome 2 problems. 1 is lobing issues experienced with dual drivers in a MMT arrangement, as well as putting the tweeter in the center makes the system act as more of a point source.

 

Blizzard, Just caught up with this thread. I would like ask about your belief on lobing problems for MMT designs. 20 years ago when I was building DIY speakers, and doing a lot of speaker and in-room computer modelling, I came to the following conclusions:

 

1. With low order xovers, e.g. 3rd order acoustic xover MTM, there were better vertical lobing behaviour with an MTM over an MMT.

 

2. With even high order xovers, e.g. 8th order acoustic xovers, there were actually no vertical lobing problems in my modelling, in fact, some response advantages in having the mid drivers close together.

 

With your current speakers (as in your photos), for which I assume you are using high order xovers, have you done any measurements at low and tall "listening positions" (e.g sitting on the floor/standing tall) that confirm vertical lobing problems. I would be interested in your measurement results.

 

Thanks

Frank

[Audio_ELF]

Deleted post...

[DigiPete]

Have a look at the Genelec SAM series, particularly the 8260 & 8351.

Both are setting new standards for sound quality, imaging, performance/size and cost/performance.

 

Genelec SAM series

 

 

Genelec vs ATC - CA

 

Advice on Genelec SAM Speakers - CA

 

Genelec speakers - CA

 

 

My blog takes you through my thoughts and reasoning behind my selection of Genelec.

Start form the beginning with "Confessions of a DigiPhile I"

 

 

Good luck & feel free to ask questions or contest my findings.

[Sam Lord]

Actually I'm not a huge fan of MTM designs. I use a different approach that I've been working on for several years.

 

The MTM approach was developed to overcome 2 problems. 1 is lobing issues experienced with dual drivers in a MMT arrangement, as well as putting the tweeter in the center makes the system act as more of a point source.

 

Problem is it limits the vertical dispersion much in the same way a ribbon tweeter does. You also have a much narrower sweet spot.

 

The method I'm using overcomes the lobing, and maintains the dispersion experienced from a small 2 way mini monitor. Yet it also takes advantage of the surface area and volume displacement of dual drivers. It makes dual drivers operate as if they are 1 in the best way I have found.

 

In the full blown system there will be dual 10's, dual 7's dual 4's and a single tweeter. The 7's and 4's will be operating as if they were single units. The level of top to bottom coherence experienced from this kind of system must be heard to be believed. Think ultimate 2 way mini monitor soundstage combined with foundation cracking dynamics.

 

Each driver will have its own 550w dedicated amp which doesn't hurt dynamics as well

 

Blizzard,

 

I like much of what you're planning but am wary of some aspects. I don't know how you deal with lobing problems from dual drivers (whether MTM or MMT); I've never heard D'Appolito or familial designs image as well as single-driver-per-band systems. I make an exception for bass drivers at least in the far-field like 10+ft. The issue is group delay beyond around +-3 degrees at the crossover points. Here is a speaker I did not design, but I did create its time-alignment adjustment algorithm:

Intuitive Audio Denali

That design was a 3-way with 1st-order xovers and weighed about 600 lbs. Still haven't heard its equal, but I don't get out much.

 

If I were ambitious like you I'd shell out for a set of ATC SCM40s and put each in a heavy frame above and surrounding a first-rate sub. Or I'd do the same with B&W802D3s but have the subs just outside the mains. I'd rip out the xovers put in an active digital system, but like you would adopt Jussi Laako's ultra-precise, ultra-computational mantra and ask him to create the xover routines. (Thanks for the offer of free help Jussi! Err...) I would probably go with a reasonably mild 24dB/octave for all drivers and *in practice* might only use a single notch filter for bass waves in the room--or even no room correction at all. I would keep the drivers in the baffles as is, and use variable DSP delay to allow quick changes in the listening position.

 

Well the B&Ws have good cabinetry (over 200Lbs and stiff) but the ATCs are much too light at about 70lbs. I would pour a slurry into a mold to stiffen, deaden, and weigh down the cabinets...I could tell you its composition but then I'd have to toss you overboard! I would add dead mass to the baskets too. Oops, the parameters of the enclosure change...though I think it could be made to work.

 

Drivers: I've been asleep for 10 years so bear with my ancient choices: Esotar tweeter, ATC mid dome, Cabasse 6.5" midbass, and B&W sub drivers would be ideal, but the stock ones are fine.

 

Amps: nCore baby! DAC: probably a NADAC because it would be the best 8-way one available, for a while anyway. No wait, Jussi's upcoming DSC8!

 

Cheers

[Blizzard]

Blizzard, Just caught up with this thread. I would like ask about your belief on lobing problems for MMT designs. 20 years ago when I was building DIY speakers, and doing a lot of speaker and in-room computer modelling, I came to the following conclusions:

 

1. With low order xovers, e.g. 3rd order acoustic xover MTM, there were better vertical lobing behaviour with an MTM over an MMT.

 

2. With even high order xovers, e.g. 8th order acoustic xovers, there were actually no vertical lobing problems in my modelling, in fact, some response advantages in having the mid drivers close together.

 

With your current speakers (as in your photos), for which I assume you are using high order xovers, have you done any measurements at low and tall "listening positions" (e.g sitting on the floor/standing tall) that confirm vertical lobing problems. I would be interested in your measurement results.

 

Thanks

Frank

 

I figured out a good way to deal with lobing issues in a MMT configuration. They measure the same as when a single midwoofer is used, only the lower midwoofer is just there for baffle step compensation.

[Blizzard]

Blizzard,

 

I like much of what you're planning but am wary of some aspects. I don't know how you deal with lobing problems from dual drivers (whether MTM or MMT); I've never heard D'Appolito or familial designs image as well as single-driver-per-band systems. I make an exception for bass drivers at least in the far-field like 10+ft. The issue is group delay beyond around +-3 degrees at the crossover points. Here is a speaker I did not design, but I did create its time-alignment adjustment algorithm:

Intuitive Audio Denali

That design was a 3-way with 1st-order xovers and weighed about 600 lbs. Still haven't heard its equal, but I don't get out much.

 

If I were ambitious like you I'd shell out for a set of ATC SCM40s and put each in a heavy frame above and surrounding a first-rate sub. Or I'd do the same with B&W802D3s but have the subs just outside the mains. I'd rip out the xovers put in an active digital system, but like you would adopt Jussi Laako's ultra-precise, ultra-computational mantra and ask him to create the xover routines. (Thanks for the offer of free help Jussi! Err...) I would probably go with a reasonably mild 24dB/octave for all drivers and *in practice* might only use a single notch filter for bass waves in the room--or even no room correction at all. I would keep the drivers in the baffles as is, and use variable DSP delay to allow quick changes in the listening position.

 

Well the B&Ws have good cabinetry (over 200Lbs and stiff) but the ATCs are much too light at about 70lbs. I would pour a slurry into a mold to stiffen, deaden, and weigh down the cabinets...I could tell you its composition but then I'd have to toss you overboard! I would add dead mass to the baskets too. Oops, the parameters of the enclosure change...though I think it could be made to work.

 

Drivers: I've been asleep for 10 years so bear with my ancient choices: Esotar tweeter, ATC mid dome, Cabasse 6.5" midbass, and B&W sub drivers would be ideal, but the stock ones are fine.

 

Amps: nCore baby! DAC: probably a NADAC because it would be the best 8-way one available, for a while anyway. No wait, Jussi's upcoming DSC8!

 

Cheers

 

I'm actually building everything from scratch. I'm not using commercial finished products.

 

Those are some nice driver choices, but that's more 15 year ago era stuff. However the ATC mids are still the best soft domes around. Dynaudio stopped selling raw drivers to 3rd parties (except a select few) years ago. But they have released some drivers for the DIY market recently with "Dynaudio" stamped on the frame. I think the same with Cabasse. They got out of the 3rd party market.

Focal did as well back in 2003. And Audax got bought out and dissolved.

 

 

Today's state of the art choices would come from companies like Accuton, Scan-Speak, Seas, Eton, PHL, Audio Technology and Raal. Of course the good old British companies Volt and ATC are still making the same super quality drivers they have been doing for years.

 

There's many more choices than that out there, but there's a hell of a lot of good stuff in the pages of their catalogs. Unless your looking for crazy high end full range drivers, you don't need to look much further. Although Seas has a couple of them.