Teaser

[Zvu]

I've been working on a loudspeaker for some time - few months actually because of lack of spare time. Things are near completion. I can not yet disclose all the details (drivers used and crossover schematic) because there is a possibility it becomes a commercially available product. Initial assessment is that end price will be around 850 euros/pair. If endeavors to become a commercial product fail i'll post all the technical details and drawings here. If this violates any of the forum rules (i'm aware it could be looked at as advertisement attempt) feel free to throw tomatoes at me and delete the thread, but i'm genuinely so excited about the performance and the concept of this volkslautsprecher that i couldn't keep my mouth shut.

So, that out of the way... It's a standmount three way, high performance and extremely high value loudspeaker - made in Europe. Not too many of those floatin' around i guess. One of my beliefs is that principles known for 50 years shouldn't cost as much as it is usually charged. So, although it is relatively low priced, it incorporates much of what i know and strive to. Only thing i didn't use are Kef's port technology for reducing port resonance - patent protected. It should be low diffraction but without roundovers - rather bevels (thanks to Jon Marsh and late Charles Hansen), flat frequency response, wide directivity were the main goals. Beside that it had to be compact with F3 around 40Hz-45Hz suited to smaller rooms - 30sqm maximum recommended. Also, for small rooms people tend to buy two ways because everyone offers almost exclusively that. Large manufacturers don't want to bother with standmount threeways - crossover and additional driver plus development process cost almost double in regard to two way and in that sense profit is much lower. Well, i thought - why does the profit has to be 400%-800% as usually is. Not making a living out of it delivers you from that kind of traps. There are lots of kits available (Statements monitor for example) but not everyone can or knows how to do it. Large chunk of money paid for these speakers actually goes on drivers, crossover parts, woodwork and assembly (19mm mdf, elco bipolar only for bass, air coils and foil caps for tweeter and mid). Design costs almost nothing since i'd be doing this anyway, just for the fun of it.

Few pics are in order. Yours truly with help of very skilled photographer - as all high end manufacturers do but the budget for that was a bit tight:

https://i.postimg.cc/dQgGdG1Z/Zvu.jpg

#photo of anechoic chamber with this loudspeaker and fancy measuring equipment

#photo of some fine lookin' lady in minimalist living room with speakers painted like couch and one of the walls

#photo of a famous musician in clinch with his loving instrument and these speakers behind him

#photo of nervous mixing engineer using that last bit of accuracy out of this speakers for his mix


Now that less important bit, measurements. 1 meter distance, gated, 1dB gridline

0, 10 and 20 deg off axis

https://i.postimg.cc/9XDGrLWj/0-10-20.png

30, 40 and 50 deg off axis

https://i.postimg.cc/GmCYgrvc/30-40-50.png

60, 70 and 80 deg off axis

https://i.postimg.cc/P5QDBcM1/60-70-80.png

0 and 90 degrees off axis - 5dB gridline

https://i.postimg.cc/dtdr9DkH/0-90.png

And no, the "professional photographer" didn't get up until we finished everything

https://i.postimg.cc/pTZTXhTT/photographer-photographed.jpg

Those were made two nights ago - around 01:30am. There was much yawning and four coffee's tomorrow but it was fun doing it and we were very pleased with results.

More measurements to come - distortion (still waiting for some crossover parts), waterfall etc.

[Juhazi]

Interesting!

[ergo]

Nice substitute space for anechoic room... and good enough to see low enough in frequency
Not clear if you rotated the speaker or a mic around it (just curious)?

Good luck with commercializing these, I would also say that a selection of affordable stand mounting 3ways is more than scarce in Europe. So the market niche might be there.

[cotdt]

I don't think such speakers exist at the price point you mentioned.

[Zvu]

Even at Kef they measure outdoor for highest accuracy. NRSC where PSB is developed uses anechoic room that is precise down to 80Hz, and then they correct the response. Similar to what i'm doing here since i have to do nearfield measurements to see what really happens down to 40Hz. I rotated the speaker and did small corrections of mic position since whole Y axis moves a bit when you rotate the cabinet.

If this goes into production, it will be available in Europe at first but in USA also and price difference shouldn't be significant. In Europe you can buy Kef R3 (updated version of Kef R300) or Elac UB5, in USA there are Polk LSiM703 and BMR Philharmonitor on top of first two. Those are real three way stand mounts, not two way with super tweeter or some similar mumbo jumbo. Two ways, on the other hand, are growing like mushrooms - every possible shape, flavour, colour and size.

Main planned advantage of these, if it happens, will be sound quality with no marketing bs, measurably good performance - overachiever, flexibility and consistency. You'll be able to set the sound per your room and preference. Shunt resistors in L-pads for mids and tweeters will be external, mounted on the back side. When bought it will measure pretty much as seen above. But, if you want to make the tweeter or mid 0.5dB or 1dB hotter or lower, you just unscrew the resistor and put different proposed value for that. 10W resistors are cheap, shunt ones don't influence the sound quality so you can play with loudness levels as much as you want (maximum and minimum values being predefined). I've seen that Gryphon Mojo does that for tweeter and i don't understand why the manufacturers don't do that more often. You're stuck with their voicing. Active studio monitors have it, why wouldn't passive home speakers? So this is kinda loudspeaker made out of rebelliousness. I plan to change that because it costs just a few bucks and there is some work involved but it is very useful. Without adjustable Lpads though - i really don't like those. And either an adjustable length port or a set of two port tubes for tuning to your room and preference. That combined with measuring every pair made before it leaves here should do it.

If it doesn't happen that way, it won't happen - those were my conditions. We'll see if it holds.

[ergo]

....You'll be able to set the sound per your room and preference. Shunt resistors in L-pads for mids and tweeters will be external, mounted on the back side. When bought it will measure pretty much as seen above. But, if you want to make the tweeter or mid 0.5dB or 1dB hotter or lower, you just unscrew the resistor and put different proposed value for that. 10W resistors are cheap, shunt ones don't influence the sound quality so you can play with loudness levels as much as you want (maximum and minimum values being predefined). I've seen that Gryphon Mojo does that for tweeter and i don't understand why the manufacturers don't do that more often. You're stuck with their voicing. Active studio monitors have it, why wouldn't passive home speakers? So this is kinda loudspeaker made out of rebelliousness. I plan to change that because it costs just a few bucks and there is some work involved but it is very useful. Without adjustable Lpads though - i really don't like those. And either an adjustable length port or a set of two port tubes for tuning to your room and preference.

I agree to that and been wondering the same. One speaker tuning to cover all the types of rooms just can't be done imho too. Instead of people trying to tune their sound with speaker/line and power cables this should be a default first step instead.

[dwk]

If this goes into production, it will be available in Europe at first but in USA also and price difference shouldn't be significant. In Europe you can buy Kef R3 (updated version of Kef R300) or Elac UB5, in USA there are Polk LSiM703 and BMR Philharmonitor on top of first two. Those are real three way stand mounts, not two way with super tweeter or some similar mumbo jumbo. Two ways, on the other hand, are growing like mushrooms - every possible shape, flavour, colour and size.

There is also the NHT C3, which appears to be very close in concept to what you're designing and appears to be a real bargain. I considered them before ultimately going with the R3.

[Zvu]

Just looked at some review and measurements of it. Great little loudspeaker and yes, similarly placed goals to what i'm doing. I like that aesthetics, though it is a bit challenging since every little thing is visible on black piano finish. My Kef R300's were piano black and it just acted as a dust collector. Sold it to a friend when i finished the mods.

[cotdt]

There is also the NHT C3, which appears to be very close in concept to what you're designing and appears to be a real bargain. I considered them before ultimately going with the R3.

Oh yes the NHT C3 is the closest in concept to Zvu's idea. I have various NHT speakers, and unlike most commercial speakers, they have a very flat response and measure very well distortion-wise. Unfortunately they use one too many electrolytic capacitors in the crossover (which is otherwise well designed), and poor quality inductors, thus there is a colored, plasticky sound. Sounds amazing after rebuilding the crossovers however. It just shows that one can use low cost drivers that sound just as good as expensive units, but it's much harder to save money on the crossover without affecting the sound.

[Zvu]

I still need to measure few inductors from different manufacturers to see what will result in lowest distortion. Woofer crossover is 24dB/o electrical plus RLC (ouch). I need high quality inductors to keep the distortion as low as possible. Capacitors in woofer crossover are largish in values so they can't really be anything but the elco bipolars - mostly because of size. I'm listening the prototype as we speak with elco bipolars. I've tried iCar Ecofill motor run mkp's (only mkp caps of that large values i could find) for woofer just to see if there will be any audible difference. I couldn't hear anything between elcos and foil caps on woofer. Elcos in my schematic do have small value resistors in series, for fine shaping woofer response, so it is possible that in that configuration type of capacitor doesn't make a difference.

[ergo]

I just talked to one of my audiophile friends last week who builds and experiments a lot. He had been listening to bipolar elco versus two polarized elcos in series and center point DC biased with 9V battery. According to him the DC biased elco scenario improves the sound a lot... while I've not heard it I would tend to believe that as the operating mode is probably more favorable in the dielectric layer of the cap.
The only problem is that it is probably not feasible to use such solution in commercial speaker even if the battery would last 10 years and price wise it might bot be that much cheaper anymore either.

[Zvu]

There is also the NHT C3, which appears to be very close in concept to what you're designing and appears to be a real bargain. I considered them before ultimately going with the R3.

I've just checked NHT C3 some more. Kef R3 is much better choice if no subs are used. C3 is a closed box and doesn't go low enough to be used without subs in my opinion. On the other hand R3 will do bass and sounds full and punchy even without subs.

I just talked to one of my audiophile friends last week who builds and experiments a lot. He had been listening to bipolar elco versus two polarized elcos in series and center point DC biased with 9V battery. According to him the DC biased elco scenario improves the sound a lot... while I've not heard it I would tend to believe that as the operating mode is probably more favorable in the dielectric layer of the cap.
The only problem is that it is probably not feasible to use such solution in commercial speaker even if the battery would last 10 years and price wise it might bot be that much cheaper anymore either.

Charge coupled crossovers were used by JBL. I don't know if their reason was about saving money and using cheaper components or there is some other advantage for using it. It didn't catch my interest enough to try it back when i made my own version of econowaves. I do remember some positive comments from the guys that did.

[Zvu]

Few more details.

Horizontal response 0 to 90 degrees - averaged

https://i.postimg.cc/5Nmv5XP9/image.png

Impedance

https://i.postimg.cc/rwF4fqb1/image.png