"The Clue" - ny amerikansk högtalare

[MagnusÖstberg]

Hi James!

Such low crossover frequency as 40-50hz puts large demands on the main to be able to move substantial amount of air.

Don´t you see the advantage of having the larger woofers operate up to 80-100hz as that definetly makes things easier for the mains who can concentrate on upper bass and above? Why put that extra stress on them?

Hi MagnusÖstberg,

I agree with you.

What I had stated it previously, but I forgot to mention again in the last post, is that I always "shelf down" my mains by approximately 6 to 12 dB to reduce the load on the main loudspeakers, but keep them active at that reduced level from 80 or 100 Hz down to their lower limit, to provide a more effective integration with the subwoofers and to create a greater number of diverse sources of bass in the room for further improvements in smoothness.

The greater the number of subwoofers that are added, the greater the amount of LF amplitude reduction can be applied to the mains, reducing their output requirements.

Make sense?

- James

Hi!

I must admit I don´t fully understand the meaning of extending the mains further down than 70-100hz, as they still will give some output down to around 50-70hz, even using a 5th order acoustic roll-off. This still means that the bassmodules can be placed fairly free from the mains because of the long wavelenght without compromissing.

I would say that the greater numbers of subwoofers used we will get greater LF amplitude reduction in the subwoofer range, thus increased headroom in the bass range. And ofcourse the acoustic advantage one can achive using multiple woofers spread out. But there will be no reduction in stress for the mains using my way, that is true.

However, I like the idea of letting more stress off the mains. This will however, as I see it, result in special demands om both filter and woofers. Let us play with the thought of gradually reduce the main output under 300hz with 6db/octav down to 75hz where they start rolling-off with 30dB/octav. This would mean that the woofers would have to be able to play up to +600hz - and placement would be more critical.

All in all, I think this route is too complex and will not give bennefit in comparison with the eefort put in. Better to make sure the main can handle all the output you need as long as they are cut crossed over acustically with 5th order around 70-90hz.

What is your thoughts around this?

Best regads
Magnus

[celef]

2) using a near field woofer close to the listening seat, such that the dominant arrival is the direct arrival from the woofer itself (this is a superior technique not commonly used in the industry as of yet. I believe this approach is ahead of its time and will become a standard in another 5 to 10 years. We have developed systems using this approach that consistently outperform all other approaches)

i'm surprised none haven't commented the above, i'm not sure i understand the meaning of it but it sounds to me like the subwoofer placement in early home cinema setups, like coffee table subwoofers, i'm sure this is not what you're saying?

[Nattlorden]

I did think that was what he was saying.... but envisioned element facing listeners, not down as in most of those coffee-table subwoofers.

( And I've begun thinking if this placement wouldn't work fine for a couple of subs for my home theater setup (note for James - not the system described above, the tv/home theater room is a much smaller one upstairs) )

[paa]

I wonder if this concept is similar to the products called "basstöd" by ino?

paa,

I am not familiar with "basstöd".

Can you explain the concept?

Thank you,

- James

Basstöd may be translated to: "Bass Support".
It's a subwoofer connected with a special crossover together with the main speaker, and it may also have a more powerful driver than the main speaker bass driver.
However, I do not know all the details, maybe someone who know more can fill in the gaps.

[paa]

2) using a near field woofer close to the listening seat, such that the dominant arrival is the direct arrival from the woofer itself (this is a superior technique not commonly used in the industry as of yet. I believe this approach is ahead of its time and will become a standard in another 5 to 10 years. We have developed systems using this approach that consistently outperform all other approaches)

i'm surprised none haven't commented the above, i'm not sure i understand the meaning of it but it sounds to me like the subwoofer placement in early home cinema setups, like coffee table subwoofers, i'm sure this is not what you're saying?

I'm wondering if a listener moving relative to the closely placed subwoofer would upset the balance of the percieved frequency response.

[Jacro]

Okay Gentlemen,

It appears that there are no more questions.

I just wanted to say that I enjoyed interacting with you.

If there is anything more that you wish to discuss or if you feel there is another area in the forum that you would like me to participate in, please let me know.

All the best,

- James

PS - Also, if I missed anyone's question, I apologize. If there is something remaining unanswered, please let me know and I'll do my best to provide an answer.

[Jacro]

2) using a near field woofer close to the listening seat, such that the dominant arrival is the direct arrival from the woofer itself (this is a superior technique not commonly used in the industry as of yet. I believe this approach is ahead of its time and will become a standard in another 5 to 10 years. We have developed systems using this approach that consistently outperform all other approaches)

i'm surprised none haven't commented the above, i'm not sure i understand the meaning of it but it sounds to me like the subwoofer placement in early home cinema setups, like coffee table subwoofers, i'm sure this is not what you're saying?

I'm wondering if a listener moving relative to the closely placed subwoofer would upset the balance of the percieved frequency response.

paa,

That is a very good observation.

This one of the aspects that must be properly coordinated with the specific system conditions. It is rather complex to generalize in short discussion, but if one mounts the woofer close enough to the listener that it is within the theoretical "near-field" condition, then inverse-square-law does not apply and the system is not particularly sensitive to movement of the listener's head.

If one places the woofer somewhat farther away, just outside of the theoretical "near-field", then the head movement will not approach a great enough change in distance to significantly alter level, even when inverse-square-law is in effect, due to the ratio of head movement to total distance being quite small.

[[As you may know, “near field” is used as a general term in audio, meaning listening close to a sound source, such that the direct sound to reflected sound ratio is substantially elevated to the point that the environmental effects are minimal. This general version of ‘near field’ should actually have a different name, such as ‘close field’ or ‘direct field’ listening.

“Near-field” is actually a specifically defined acoustical term that is based the precise relationship of the dimensions of the emission source and frequency/wavelength. In the true “near-field”, the sound field maintains greater directivity and more consistent output vs. distance, than it does in the “far-field”.]]

When properly set up, this change in head movement will have an insignificant effect, but the advantages relative to elimination of modal effects will be quite impressive. Many consider the sonic effect on their systems to be quite transformational while substantially obviating the need for multiple subwoofers.

Of course, this approach is less satisfying for listening while wandering around the room, but for specified seated listening for up to 3 or 4 people, it can be quite effective.

Cheers,

- James

[Jacro]

Hi James!

Such low crossover frequency as 40-50hz puts large demands on the main to be able to move substantial amount of air.

Don´t you see the advantage of having the larger woofers operate up to 80-100hz as that definetly makes things easier for the mains who can concentrate on upper bass and above? Why put that extra stress on them?

Hi MagnusÖstberg,

I agree with you.

What I had stated it previously, but I forgot to mention again in the last post, is that I always "shelf down" my mains by approximately 6 to 12 dB to reduce the load on the main loudspeakers, but keep them active at that reduced level from 80 or 100 Hz down to their lower limit, to provide a more effective integration with the subwoofers and to create a greater number of diverse sources of bass in the room for further improvements in smoothness.

The greater the number of subwoofers that are added, the greater the amount of LF amplitude reduction can be applied to the mains, reducing their output requirements.

Make sense?

- James

Hi!

I must admit I don´t fully understand the meaning of extending the mains further down than 70-100hz, as they still will give some output down to around 50-70hz, even using a 5th order acoustic roll-off. This still means that the bassmodules can be placed fairly free from the mains because of the long wavelenght without compromissing.

I would say that the greater numbers of subwoofers used we will get greater LF amplitude reduction in the subwoofer range, thus increased headroom in the bass range. And ofcourse the acoustic advantage one can achive using multiple woofers spread out. But there will be no reduction in stress for the mains using my way, that is true.

However, I like the idea of letting more stress off the mains. This will however, as I see it, result in special demands om both filter and woofers. Let us play with the thought of gradually reduce the main output under 300hz with 6db/octav down to 75hz where they start rolling-off with 30dB/octav. This would mean that the woofers would have to be able to play up to +600hz - and placement would be more critical.

All in all, I think this route is too complex and will not give bennefit in comparison with the eefort put in. Better to make sure the main can handle all the output you need as long as they are cut crossed over acustically with 5th order around 70-90hz.

What is your thoughts around this?

Best regads
Magnus

Magnus,

I agree, that IF your main left/right loudspeakers cannot handle low frequencies without distortion, then the approach I am suggesting will not work properly. In the case of weak main loudspeakers I would recommend a few other approaches.

But, if your main loudspeakers are capable of full system output with low distortion down to 40 or 50 Hz (with frequencies below 100 Hz shelved down by at least 6 dB) then the room modes can be smoothed by using only one or two subwoofers and the sound quality will be very good.

If the main loudspeakers are weak at low frequencies and must be high passed at higher frequencies then 4 subwoofers carefully placed will usually be necessary.

Each approach has tradeoffs, but I prefer to have my trade-off be one of "quantity", not "quality". I can always improve "quantity" of output by incorporating mains or subwoofers that have higher output capability, but improving the sound "quality" of the final result is more difficult and requires specialized efforts.

I believe the complexity is reasonable, particularly since the improvement in quality is significant.

I hope this makes sense.

Let me know if I am still not addressing your question in the manner you are looking for.

- James

[paa]

James, would you think the HOM reduction foam also works as an acoustic lens that further smothes the dispersion whithin the desired coverage angle?

Interesting idea.

The current goal of applying foam to a waveguide to reduce HOMs is to be able to maintain consistent absorption such that directivity is not changed from the ideal directivity of the waveguide. Correctly applied, directivity does not change when the foam is applied.

Attempting to use the foam to change directivity does add a degree of complexity that may be difficult to fully characterize. As one changes absorption rates, it must be achieved in a manner that the absorption discontinuities don't increase HOMs, simulating diffractive effects.

That said, the concept of using the foam to alter directivity while reducing HOMs may be a very good idea. The ability to provide an addition variable to control directivity in waveguides may allow one to relax the directivity capability of a waveguide in order to achieve an improvement of some other parameter (such as efficiency, or bandwidth, etc.), and then re-optimize the directivity with a variable density foam insert.

Definitely worth exploring.

- James

I believe that acoustical transparent foam (now often called "filter foam") was claimed to behave like an acoustical lens, expanding the directivety of narrow beaming tweeters, when it was introduced in the seventies. To what extent that really worked I have no idea.

[Jacro]

Okay Gentlemen,

It appears that there are no more questions.

I just wanted to say that I enjoyed interacting with you.

If there is anything more that you wish to discuss or if you feel there is another area in the forum that you would like me to participate in, please let me know.

All the best,

- James

PS - Also, if I missed anyone's question, I apologize. If there is something remaining unanswered, please let me know and I'll do my best to provide an answer.

[jeppe]

Hello James, I hope you still visit faktiskt every now and then.

I´ve been living with (the clue) now for about a month and I just want to say a few words about them. They are not good or very good but utterly brilliant!

I bought them unheard and now I can´t stop listening to them.
thanks!!

[celef]

jeppe, berätta gärna hur du gjorde för att komma över ett par! och vad fick dig att köpa olyssnat? beställde fredrik ett par oxå?

[jeppe]

mailade Sjöfn och fick det glädjande beskedet att dom har sänkts till 999 dollars och exporteras direkt från Sjöfn hifi, alltså inga omvägar via butik

Tog väl en vecka tills jag hade dom. Kostade allt som allt (ink moms) 7700 sek. Vet inte om Fredrik har beställt.

Varför köpa olyssnat? tja, nyfikenhet.. jag var ganska säker på att dom skulle vara precis så pass bra som jag tycker att dom är

[celef]

tack för svar! nyfiken som jag är: köpte du högtalarna på grund av skriverierna här eller skriverier någon annanstans, typ i hifimagasin eller andra internetforum?

[jeppe]

hmm, ja olika forum och recensioner stärkte köpbeslutet sen var det mycket hur konstruktören kan förklara varje aspekt av konstruktionen och tänket bakom lösningarna.

[Nattlorden]

hmm, ja olika forum och recensioner stärkte köpbeslutet sen var det mycket hur konstruktören kan förklara varje aspekt av konstruktionen och tänket bakom lösningarna.

[Jacro]

Hello James, I hope you still visit faktiskt every now and then.

I´ve been living with (the clue) now for about a month and I just want to say a few words about them. They are not good or very good but utterly brilliant!

I bought them unheard and now I can´t stop listening to them.
thanks!!

Hello Jeppe,

Thank you for your enthusiastic comments!

(the clue) has been a rewarding project. It is one of the lowest priced loudspeakers I have ever designed, but by incorporating the novel sound field construct, it provides advantages over more expensive approaches.

Most of all, we wanted (the clue) owners to have more fun with music, so I'm very happy to hear that you are enjoying your new loudspeakers.

Cheers,

- James

[metheny]

(the clue) has been a rewarding project. It is one of the lowest priced loudspeakers I have ever designed, but by incorporating the novel sound field construct, it provides advantages over more expensive approaches.

Most of all, we wanted (the clue) owners to have more fun with music, so I'm very happy to hear that you are enjoying your new loudspeakers.

Cheers,

- James

Hi, sorry for not having read the whole thread, the answer might already have been given. But I'm wondering if the elements are of custom design or "off-the-shelf"? Will it be possible to buy the speaker as a kit, i.e just the filter components and the elements together with instructions on how to build the boxes?

[_Fredrik_]

hmm, ja olika forum och recensioner stärkte köpbeslutet sen var det mycket hur konstruktören kan förklara varje aspekt av konstruktionen och tänket bakom lösningarna.

Fy fan va fett, grattis. Nej jag har inte beställt, jag har väntat på att du ska göra det först.

Va roligt att du är nöjd!

[Jacro]

(the clue) has been a rewarding project. It is one of the lowest priced loudspeakers I have ever designed, but by incorporating the novel sound field construct, it provides advantages over more expensive approaches.

Most of all, we wanted (the clue) owners to have more fun with music, so I'm very happy to hear that you are enjoying your new loudspeakers.

Cheers,

- James

Hi, sorry for not having read the whole thread, the answer might already have been given. But I'm wondering if the elements are of custom design or "off-the-shelf"? Will it be possible to buy the speaker as a kit, i.e just the filter components and the elements together with instructions on how to build the boxes?

Hi Metheny,

The tweeter/waveguide and woofer elements are proprietary (not off the shelf). A kit is not available at this time.

To replicate the performance of a production version of (the clue) is difficult to realize in a kit, due to the final "in-box" calibration process. Currently, it would cost more to produce a high-performance kit than a standard production unit, as we would have to build the kit into an enclosure, complete the final calibration process and then disassemble the elements and package them in kit form.

(the clue) wasn't designed with the idea of making a kit version of the same performance ability.

That said, if there are enough requests, we will revisit the exploration of how to make a kit with the same sound quality as the standard version.

Thank you for your interest. I will add +1 to our kit request list.

All the best,

- James

[luminous]

Hi Jacro,

I have been reading your posts in this thread with great interest. I was wondering if you would like to share your view on this topic:

How can you tell, by taking measurements, that you have achieved a neutral perceived timbre (flat perceived frequency response) in a room?

Most people seems to agree that the goal isn't just a flat in-room frequency response, but there doesn't seem to be a generally accepted answer to this question either.

Regards, Viktor

[jeppe]

hmm, ja olika forum och recensioner stärkte köpbeslutet sen var det mycket hur konstruktören kan förklara varje aspekt av konstruktionen och tänket bakom lösningarna.

Fy fan va fett, grattis. Nej jag har inte beställt, jag har väntat på att du ska göra det först.

Va roligt att du är nöjd!

Tack! jodå väldigt nöjd, dom är verkligen plug and play i mitt rum. Har aldrig hört mitt usla rum ljuda så fint. Har du beställt nu då?!

[Ragnwald]

jeppe, vad fick du betala allt som allt, för ett par?

[Audix]

Jeppe, var i sverige finns du? Vill du ta emot nyfikna besökare?

[Lust]

jeppe, vad fick du betala allt som allt, för ett par?

mailade Sjöfn och fick det glädjande beskedet att dom har sänkts till 999 dollars och exporteras direkt från Sjöfn hifi, alltså inga omvägar via butik.

Tog väl en vecka tills jag hade dom. Kostade allt som allt (ink moms) 7700 sek.

[Ragnwald]

Ok, tack.

[jeppe]

Jeppe, var i sverige finns du? Vill du ta emot nyfikna besökare?

Bor i närheten av Tumba i Stockholm men jag är mitt i en separation så det är tyvärr inte aktuellt med besök

[metheny]

Har någon jämfört dessa med piP?

[metheny]

mailade Sjöfn och fick det glädjande beskedet att dom har sänkts till 999 dollars och exporteras direkt från Sjöfn hifi, alltså inga omvägar via butik [..] Kostade allt som allt (ink moms) 7700 sek.

$999 ~ 6300 SEK, moms 25 %, ~1500 kr, och då är inte frakten medräknad. Hur har du räknat? Skickas de utan fraktkostnad?

[Lust]

Bor i närheten av Tumba i Stockholm men jag är mitt i en separation så det är tyvärr inte aktuellt med besök

Det är då faen vad svårt många kvinnor har med nya högtalare ...