DIY Line source with 3.5 full range drivers and ribbon tweeter

[haraldo]

last year I was at a shop listening to a set of line source speakers, very very expensive things, and sounding so good, completely free of any kind of grain and distortion, limitless dynamics, ability to play incredibly loud, almost to the sense of there being absolutely no limits.

Never ever heard Pink Floyd, The Wall sound so good, I could swear that I was listening to a different, improved master, but that was not the case.....

Downsides, price of these things, larger one being close to $ 40.000

Now look at these pictures, they look exactly like the retail version of the peerles / vifa drivers you can get here for just $32 per driver
http://www.madisound.com/catalog/index.php?cPath=45_241_282

The producer, Adyton states that they use Peerless drivers in their speakers...

with 18 drivers in each speaker you get to about $1200 in drivers and adding tweeter.

There are absolutely some challenges with a design like these where bass/midrange is line source and tweeter is point source, but auditioning these things, I have to say this works, and it works exceedingly well !!!

Please Correct me if I'm wrong on this, but these are some thoughts

• With so many of these full range drivers, even at very very high volumes, the output from each driver is not even close to their limits, so distortion is close to nothing
• The line source makes them less susceptible to room issues and first reflection is not much of an issue
• It's said that these drivers can go with very very simple crossovers.....
• The lower limit of these drivers are around 80Hz, so two good sub's are always needed

Looking at list price of drivers adding up to probably around $1500 for both speakers, it's a good way up to retail price of $38.000, and I don't think the cabinet and what's else inside would be so special.

Oooooh, perhaps they use this superduper quark quanticied cryogen treated cable that has been treated in vacuum and brought to zero G by space shuttle to organize electron's properly according to the proton rotation's sequencing pattern, that may make a difference and is very exoensive.

Wonder if these could be a good candidate for a DIY construction, sealed or TL? and it won't break the bank trying things like these....
There are also many other similar drivers

Any remarks to these thoughts...... anyone?

 

[MidnightSensi]

I know it's a dirty word around here, but look into Amar Bose's papers on tweeter arrays from his days at MIT.

 

[bandphan]

If you search the loudspreaker forum for "Roger Russell", there is a good discusion on line arrays.

 

[haraldo]

Certainly some interesting reads here by searching for Roger Russel, I have read some of his papers too, which is quite interesting...

And, what bugs me is that for $38.000 these are probably the best selling high end speakers around here now. I just don't see how what gets in there can be sold for this amount.

Well, to throw in a bunch of high quality full range drivers, extremely high quality tweeter, full digital x-over (Like Behringer Ultracurve Pro DEQ2496) and good amplifiers.... still not very expensive rig.

What I was really thinking about for a long time is to put this thing into a Transmission line... I'm not sure what differences there will be if it's 1/4, 1/2 or 1/1 length TL line, will there be any audible differences from these different setup's?

Anybody having good ideas on good TL loading of such speakers?

Driver selection could be sth like
upperwoofer/mid/lower-tweeter or this

tweeter

Certainly looks for quite heavily equalization to make fullrange drivers to be linear.....

Don't know if these are good or very bad ideas, but I'm sure I'm going to hear some straight thoughts on this

 

[annunaki]

If the driver itself is not extremely linear in design and does not have extremely low power compression, use of eq should be shyed away from (if being used to correct for natural response errors). You will have a speaker pushing it's linear limits, heading for failure, high amounts of distortion, and squashed dynamic ability.

 

[MidnightSensi]

Is it just me or is the center channel bowed down in the middle?

 

[highfigh]

Any remarks to these thoughts...... anyone?

"Looking at list price of drivers adding up to probably around $1500 for both speakers, it's a good way up to retail price of $38.000, and I don't think the cabinet and what's else inside would be so special"

How long did it take to get them to sound the way they wanted? How many drivers did they try before these were selected as the ones that would be in the final version? How much do they have invested in test equipment or consulting fees (if they don't do their own testing)?

building these after the engineering and testing is done is cheap. It's all the stuff before they go to market that raises the price. Without knowing their sales projections, it's hard to know when they think they'll break even.

Of course, it could be one of those "We're not here to make friends, we're here to make money" things, too.

 

[haraldo]

"Looking at list price of drivers adding up to probably around $1500 for both speakers, it's a good way up to retail price of $38.000, and I don't think the cabinet and what's else inside would be so special"

How long did it take to get them to sound the way they wanted? How many drivers did they try before these were selected as the ones that would be in the final version? How much do they have invested in test equipment or consulting fees (if they don't do their own testing)?

building these after the engineering and testing is done is cheap. It's all the stuff before they go to market that raises the price. Without knowing their sales projections, it's hard to know when they think they'll break even.

Of course, it could be one of those "We're not here to make friends, we're here to make money" things, too.

Absolutely very valid point and it has taken them nany years to develop these and there's no cheap components inside, only the very best quality stuff in x-over and more.....

But still, there has to be a consistency between the value of the parts and retail price.

 

[haraldo]

Is it just me or is the center channel bowed down in the middle?

You have eagle eyes, didn't notice this but the center channel is certainly not straight, don't know why this is so.......

 

[annunaki]

I am thinking it is an optical illusion from a curved front baffle or rear of the enclosure.

 

[haraldo]

If the driver itself is not extremely linear in design and does not have extremely low power compression, use of eq should be shyed away from (if being used to correct for natural response errors). You will have a speaker pushing it's linear limits, heading for failure, high amounts of distortion, and squashed dynamic ability.

Well, looking at the drivers that I may consider, they only need compensation to cut peaks and perhaps very slight adjustments of dips, and then..... the eq will not put any more "pressure" on the drivers, in which way, I guess the eq would be pretty safe, right?

 

[annunaki]

If it is taming peaks and not to boost response that should be fine. It will not place any undue stress on the driver trying to make it over compensate for something it is physically unable to achieve. However, if it is cone breakup you are trying to tame, it will not do much to lower the induced distortion present.

 

[haraldo]

If it is taming peaks and not to boost response that should be fine. It will not place any undue stress on the driver trying to make it over compensate for something it is physically unable to achieve. However, if it is cone breakup you are trying to tame, it will not do much to lower the induced distortion present.

That's part of the problem if you look at spec's..... very hard to see what's really just peaks that may be tamed and what are breakup's, don't know if that's really easy to see from the plots..... some of the plots are made in such a way that you can't easily see the cone breakups.......

And if you buy sth like 36 drivers realizing they're no good......

 

[highfigh]

I am thinking it is an optical illusion from a curved front baffle or rear of the enclosure.

It looks like the center of that is definitely deeper than the ends- possibly to increase the spread of sound so it's not as directional when placed in a room with rows of seats.

Other than that, I got nothing, other than eliminating parallel edges and surfaces.

 

[highfigh]

Absolutely very valid point and it has taken them nany years to develop these and there's no cheap components inside, only the very best quality stuff in x-over and more.....

But still, there has to be a consistency between the value of the parts and retail price.

If it really took that long to develop these, the parts were a small percentage of the real cost. I suspect that indecision caused a lot of delays, along with a lot of trial and error testing. Also, there was most likely a good amount of fear involved when it came to making them available, at what price and what to do if people don't like the way they sound.

In my time dealing with this kind of equipment, I have seen a huge number of speakers that looked like a million bucks but sounded like a bad experiment. One local guy brought his speakers in and while they looked vaguely like something that might be found on Easter Island and had a really funky assortment of drivers, they really sounded good.

Using a lot of small drivers reminds me of another company, but I can't bring myself to type it.

 

[haraldo]

If it really took that long to develop these, the parts were a small percentage of the real cost. I suspect that indecision caused a lot of delays, along with a lot of trial and error testing. Also, there was most likely a good amount of fear involved when it came to making them available, at what price and what to do if people don't like the way they sound.

In my time dealing with this kind of equipment, I have seen a huge number of speakers that looked like a million bucks but sounded like a bad experiment. One local guy brought his speakers in and while they looked vaguely like something that might be found on Easter Island and had a really funky assortment of drivers, they really sounded good.

Using a lot of small drivers reminds me of another company, but I can't bring myself to type it.

Well, these speakers doesn't look like a million bucks, but they probably sound better than most things out there, even high profile Audio Physic speakers costing considerably more than what these do, listened to quite many of the very respected Audio physic's in the same shop as these, and the Audio Physic speakers aren't even close to what these speakers do.......... so in a sense they really provide value for money, still.....

still, it's the cost of what goes in there....... can't get it out of my mind that this must be a valuable approach for DIY'ers.....

Compare to the speakers of late John Dunlavy.... he spent many years developing one single speaker, trying out hundreds of different combinations of everything and every possible way of damping and tuning the cabinets.... every single speaker was like a huge research project.... Still, the speakers were sold at prices that reflected the cost of what went into the speakers...... so why should speakers be expensive just because somebody did a research.....

Compare this to computer software, proprietary software may come from a company doing years of research, and in the end they want to get something back so they sell their software for $2.000.000 per license, it may not be good but they sell it because people think it's good coz it's pricey..... and it's just not bloody working......
(I could mention names of s/w companies but I won't.... NOT Microsoft)

On the other hand you have opensource movements where lots of people are doing research and providing the results of that research back to the community, and also providing updates to source code back to community.... so everybody's learning and providing value to each other, and in the end you end up with great software.... and it's free.....

In a way you can compare the audio industry to the proprietary and opensource communities.... forums like this provide a lot of value and results of research provided by many skilled people around the whole world....

So there's NO WAY I'm going to pay huge amount to somebody selling a speaker just because of the fact that they've done lots of research.....

By accident, I came across these......
http://home.earthlink.net/~jmiyake/index.html


regards

-Harald

 

[highfigh]

Still, the speakers were sold at prices that reflected the cost of what went into the speakers...... so why should speakers be expensive just because somebody did a research.....

Will a business survive if it doesn't recover its expenses? No, it won't. The only way it possibly could is through creative accounting and even then, the IRS or other taxing body may not agree with the deductions taken. I don't want to be one of the few that pays someone back for developing something, either, but in some way, the company or inventor needs to be paid (unless they're independently wealthy and did it just because they wanted to). If the projected sales will be high, they can build the development into the cost of every pair and through sheer sales volume, the cost will be diluted but I doubt that spending a lot of time and money to develop something like this with the express intent of selling the final version, without any plan for being paid back could ever be looked at as a good business model.

I do agree though, a speaker system that they try to sell for $40K and have a couple thousand into doesn't sound right.

I'd like to hear the ones in the link, too.

 

[mike c]

i can understand the vertical arrays ... but a horizontal array?

 

[haraldo]

Will a business survive if it doesn't recover its expenses? No, it won't. The only way it possibly could is through creative accounting and even then, the IRS or other taxing body may not agree with the deductions taken. I don't want to be one of the few that pays someone back for developing something, either, but in some way, the company or inventor needs to be paid (unless they're independently wealthy and did it just because they wanted to). If the projected sales will be high, they can build the development into the cost of every pair and through sheer sales volume, the cost will be diluted but I doubt that spending a lot of time and money to develop something like this with the express intent of selling the final version, without any plan for being paid back could ever be looked at as a good business model.

I do agree though, a speaker system that they try to sell for $40K and have a couple thousand into doesn't sound right.

I'd like to hear the ones in the link, too.

I agree with everything you say here, and of course this is very difficult, and US or EU speaker manufacturers must have higher margins, compared to anything from Asia.... Some very fine factories had to close their doors, probably because their margins were too low, like Dunlavy Audio labs and Meadowlark Audio, all making very fine speakers, so that is sad....

So we all have a responsibility too to actually buy the good products out there, so the nice guys survive in this business.

I still don't get it when very expensive speakers have $30 drivers inside

And yes those other speakers look very interesting and with an interesting choice of drivers.....

i can understand the vertical arrays ... but a horizontal array?

Me too, dispersion pattern for center channel is totally different from the main's, at least it makes for the widest center channel you've seen

 

[haraldo]

Re http://home.earthlink.net/~jmiyake/index.html

Does anybody know how the actual series/parallel wiring of tweeters and woofers is physically set up?