AudioCircle

Audio/Video Gear and Systems => Single Driver, Wide-Bandwidth Speakers => Topic started by: jrebman on 12 Jul 2009, 10:02 pm

Title: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: jrebman on 12 Jul 2009, 10:02 pm
It's official, we are back up as an active circle, even if we are a bit on the fringe of the mainstream audio world.  At least that's how some people look at it, but if quality of sound is your metric and not percentage of overall audio equipment sales, then we all know why we're here and mainstream or not, probably doesn't bother us.

I'd like to establish the definition of a single, wide-bandwidth driver for the purposes of this circle and ask people with systems that fall outside the scope of this definition to post in a more appropriate circle.

Speaker systems that are relevant for this circle generally have the following characteristics:

a) They typically cover approximately 7 or more octaves of the audio spectrum within approximately a +/- 6 dB range.  Typically something that handles between 40 and 100 Hz on the bottom end and approximately 14k or better on the top end without the use of helper drivers of any kind -- including coaxially mounted tweeters and such.

2) Augmentation at the extremes is acceptable as long as the main driver meets the specs above and the crossovers don't limit the bandpass of the main driver to the point where it is reduced to functioning as a glorified midrange, mid/tweet, or bass/mid driver.  Taking off some load -- roughly an octave or so from the bottom end to get more mileage out of a low power amp, for example is fine.

3) Contour filters are completely acceptable -- whether they be passive or active, line-level or speaker-level, analog or digital.

 4)Of course if you have a bipole or dipole speaker whose drivers meet these requirements, they are fine to discuss here.

With regards to the discussion of ancillary equipment -- amplifiers and such, that is permitted and encouraged, but within the scope of how a particular amp works with a SD speaker.

In other words, please try to keep everything relevant to the world of single driver speakers and stay within these guidelines as best you can.

Of course all the rules about no personal attacks, being civil, and letting people disagree with you without getting your feathers ruffled apply here as they do elsewhere on AC.

Over the next week or two I'll be going through the old threads and moving some to the IGW, but only if they were overtly commercial, flame wars, or not relevant to the topic here.

So, that should be it and now that the formal rules and regs have been established, let's all have a good time and share the passion we have for this hobby.

Welcome again,

Jim

Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: Len_Dreyer on 12 Jul 2009, 10:35 pm
Hey Jim, thanks for bringing this circle back to life.

Len
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: chadh on 13 Jul 2009, 02:09 am

Jim,

Thanks so much for resurrecting this circle.

Just a quick question of clarification, though.  My setup currently satisfies the definition of a single driver system.  But I'm considering adding stereo subs to the system specifically to relieve the wide-band drivers in my main speakers from the duties of producing the lowest octaves.  If I understand your outline from above, queries I have will be acceptable in this circle only if I choose to run my main speakers full range.  But if I choose to introduce a high pass filter at around 100Hz, then my queries should be directed elsewhere.  Is that right?

Chad
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: floobydust on 13 Jul 2009, 04:22 am
 Hi Jim,

 Nice to see you back.... hope you've had a chance to work on the Gamma-1 (I've built 5 so far). While reading thru the qualifications for a full-range driver setup, I generally agree but would implement augmented support for the extreme octaves differently, specifically on the bottom.

 For better single-driver systems, I still feel that the last 1-1/2 to two octaves are the most difficult to produce and will at some point require augmentation. If I am going to augment with a sub, it will be powered and it will have a dedicated crossover. I will also attempt to use the lowest crossover frequency to maximize the single-driver system. However, once I arrive at a satisfactory crossover point, I would also provide a simple 6dB/octave passive roll-off for the single driver amplifier input. If I'm using a dedicated sub to provide that lower support, I'd rather save those extra few watts from a low-power SET for some dynamic extension (or headroom) in it's active range.

 Regards, KM
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: planet10 on 13 Jul 2009, 06:32 am
Just a quick question of clarification, though.  My setup currently satisfies the definition of a single driver system.  But I'm considering adding stereo subs to the system specifically to relieve the wide-band drivers in my main speakers from the duties of producing the lowest octaves.  If I understand your outline from above, queries I have will be acceptable in this circle only if I choose to run my main speakers full range.  But if I choose to introduce a high pass filter at around 100Hz, then my queries should be directed elsewhere.  Is that right?

That one condition eliminates FAST systems which are traditionally considered single driver systems. I think that that is a serious shortcoming of the definition.

dave
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: Mr Content on 13 Jul 2009, 06:44 am
Cool, I have been a single driver guy for several years now :D

Mr C :D
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: Bob_Brines on 13 Jul 2009, 11:39 am
I find the prohibition on helper drivers to be excessively restrictive.

On the low end, most small drivers (4" and smaller) cannot produce any real bass unless corner loaded or mounted in huge horns. The current trend is toward small drivers OB mounted. The physics of a OB of what is normally considered large is going to cut off ~300Hz give or take and is therefore prohibited here.

On the high end, while a full-range driver may produce 20kHz on axis, most 6"and larger drivers can't get to 10kHz 15* off axis. Crossing in a tweeter first order works, sort of, but there is always serious interference between the two drivers that can go rather low. A well implemented 2nd order or higher XO high enough to keep the phase shift out of the telephone band  makes for much better implementation. How many drivers have nasty peaks ~7kHz that could be easily tamed with a XO at that point?

The prohibition on filters implies that BSC filters and zobels to tame a rising response are out. You didn't specifically say so, but that can certainly be implied.

A more reasonable definition of a wide-range implementation is the main driver must produce at least the 300-3000Hz band without cross-overs in that band.  Otherwise, too many good speakers cannot be discussed here.

Bob
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: JohnR on 13 Jul 2009, 11:57 am
A more reasonable definition of a wide-range implementation is the main driver must produce at least the 300-3000Hz band without cross-overs in that band.

C'mon, that definition just makes this into the three-way loudspeaker circle  :evil:
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: Wind Chaser on 13 Jul 2009, 12:26 pm

Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle

Doesn't a single driver mean just one driver? :scratch:
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: ohenry on 13 Jul 2009, 01:24 pm
...The current trend is toward small drivers OB mounted. The physics of a OB of what is normally considered large is going to cut off ~300Hz give or take and is therefore prohibited here...


The open baffle circle can handle those.

Screw it Jim, RUN!!!   :lol:
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: JLM on 13 Jul 2009, 02:43 pm
An vintage definition of single driver speakers is one that covers 80 - 8,000 Hz. 

IMO zobels and/or baffle step circuits are OK as are any form of equalization. 

Designs that use multiple drivers (of the same design) or crossovers can apply elsewhere.  OTOH, adding a subwoofer doesn't affect the single driver speaker design, so my vote would be to allow them into the discussion.
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: jrebman on 13 Jul 2009, 03:31 pm
Well, good morning.

Yes, there may be some *minor* tweaking to the definition -- mostly as it pertains to bass augmentation.  No compromises on the high end though as really then we're just talking about 2 or 3 ways with a super-mid.  I'll do some thinking and some research on some of the better drivers and see what actually pans out.

I inadvertently left out any statement about contouring filters, and of course they should be fine, whether active or passive, line level or speaker level, analog or digital.  contour filters do not effect the bandwidth.

This is how I'm going to think about it -- if you remove your bass and treble augmentation, is it still satisfying to listen to?

JLM, I'm not interested in the vintage definition -- I am familiar with it and don't think it produces a satisfying listening experience as defined.

Bob, as Henry said, there is an OB circle, and sorry, but the telephone range -- also something I am quite familiar with -- is not something I want to listen to, but I do agree, as stated above, that contour filters are acceptable.  However, I'll state my preference or prejudice, however you want to look at it, for line level contour filters as opposed to speaker level.  Keeping as much stuff out of the path between the amp and speaker is, IMO, something to strive for. PLLC s aren't perfect, but they are what I prefer.

Kevin, yes, about 90% done with the Gamma DAC -- just forgot to order a couple caps and one of the power manager chips but am saving up for a larger order before I get them.

Well, thanks all for chiming in, but the bottom line here is does your speaker sound satisfying with no augmentation at the extremes?  That's the real challenge in both driver and speaker design that when realized, results in a very special sound with no integration issues.

I do also want to say a bit aboue about efficiency and sensitivity -- assuming most folks know the difference -- and that is that was deliberately left out of the definition as there are some very sensitive/efficient SD designs, and some that are not so.  Yes, again, I prefer the more sensitive/efficient designs because they allow me to use the kind of amplifiers I prefer, but that's my thing.  I don't care if your SD speaker is 84 dB with a roller coaster phase/impedance curve and needs a 400 watt digital amp to make it go, as long as it falls within the scope of the definition.

-- Jim

Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: rajacat on 13 Jul 2009, 04:01 pm
What about bipole single driver designs like Omega Bipoles? Do they fit the single driver definition of this circle? http://www.omegaloudspeakers.com/products/specialapps (http://www.omegaloudspeakers.com/products/specialapps)

-Roy
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: jrebman on 13 Jul 2009, 04:26 pm
Roy,

Yes, it's already in the definition and has been since I originally wrote it.

-- Jim

Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: rajacat on 13 Jul 2009, 06:57 pm
Roy,

Yes, it's already in the definition and has been since I originally wrote it.

-- Jim

Jim,

Whoops! :oops: It was a spur of the moment reply. I should have gone back and read the beginning of the thread. :duh:

-Roy
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: JLM on 13 Jul 2009, 08:07 pm
Jim,

Please elaborate on why 80 - 8,000 Hz (over 6.5 octaves) doesn't provide a satisfying listening experience to you.  Are you after a higher frequency "balance"?  (I was just looking for a minimal entry point, not something highly desirably).
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: planet10 on 13 Jul 2009, 09:29 pm
This is how I'm going to think about it -- if you remove your bass and treble augmentation, is it still satisfying to listen to?

That is similar to my definition... the main driver needs to be able to supply a satisfying musical experience all on its own

dave
Title: Re: Welcome to the new Single Driver, Wide-bandwidth speaker circle
Post by: DaveC113 on 13 Jul 2009, 11:29 pm
A more reasonable definition of a wide-range implementation is the main driver must produce at least the 300-3000Hz band without cross-overs in that band.

C'mon, that definition just makes this into the three-way loudspeaker circle  :evil:


Agreed. I have no interest in a 300-3000 Hz driver running ob.

I also agree w/ KM... rolling off the single driver in the last 2 octaves should fit the definition too.

Hope you're doing well Jim.  :)
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: jrebman on 15 Jul 2009, 06:50 pm
Ok folks, I've updated the guidelines and hopefully they are a bit more clear and slightly broader in scope without opening too big a loophole :-).

Dave, glad to see you here -- haven't heard much from you lately.  Guessin the new job is keeping you pretty busy.

-- Jim
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: chadh on 15 Jul 2009, 07:16 pm

Jim,

the update to the guidelines are greatly appreciated.  Thanks.  I'm looking forward to absorbing as much info as possible in this circle. 

Chad
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: planet10 on 16 Jul 2009, 01:08 am
a) They typically cover approximately 7 or more octaves of the audio spectrum within approximately a +/- 6 dB range.  Typically something that handles between 40 and 100 Hz on the bottom end and approximately 14k or better on the top end

Just to be picky, 7 octaves up from 100 Hz is (100>200>400>800>1.6k>3.2k>6.4k>12.8k) is 12.8 kHz. 7 octaves from 40 Hz is 5k, 8 octaves is 10k.  9 octaves from 20 Hz is 10k.

The definition allows a driver to fall short by 2 and a bit octaves on the bottom, but only a 1/2 octave on the top. Drivers like the Pioneer B20, Goodmans Axiom 201, & Fostex FE207e don't qualify. Neither does the Radio Shack 40-1197 that got a lot of us started. Most of the 3" full-ranges fail to make the grade. If you go by Martin King's on-axis measures the Lowther DX2/3/4 don't qualify either (which probably means most Lowthers don't qualify). http://www.quarter-wave.com/Project04/Measurements.html

IMHO definition is still too restrictive.

dave
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: jrebman on 19 Jul 2009, 04:19 pm
Mike,

I split your Abby thread off into it's own topic as it was taking on a life of it's own and was straying a bit far afield for the intro sticky.

-- Jim
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: chrisby on 20 Jul 2009, 09:19 pm
Jim - my belated thanks for resurrecting this forum

the "compromises" proscribed by wide-bandwidth speaker systems,( for many of "us" frequently in combination with low powered SET amps)  brings to mind the following sentiments, recently and beautifully stated by Michael Lavorgna at 6-Moons:

Quote

Further, the attempt to apply that which we can measure (sound) to how we experience (music) is a faith-based application of science at best and flies in the face of the unrestrained listening experience. Yet by abandoning this quest for objectively better hifi performance, we have not abandoned the quest for higher fidelity as our passions drive some of us to a more and more musically engaging experience. With hifi we strive to create, not recreate, a musical event - inside ourselves.   In this sense, 'fidelity' refers to our hifi?s ability to trigger a musically engaging experiencing. Or if you prefer, we should recognize the fact that the value of music played through a hifi only becomes measurable once it hits our imagination.




http://www.6moons.com/audioreviews/roadtour19/roadtour19.html


Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: jrebman on 20 Jul 2009, 09:31 pm
Chris,  Thanks for poking your head in here and I sure hope we hear more from you.

Well, to my mind, Michael has hit the nail on the head, and absolutely beautifully.  But he's another N.J. guy, so what do you expect :D.

I was going to bring up this topic in some guise, and maybe I will and will start it with Michael's quote.

Truth and beauty -- the audiophile's dilemna.  I know where I stand.

Know anybody looking for some fonkensteens? :D  Love 'em an awful lot but really need to get with the higher efficiency thing.  You built one hell of a speaker here and people still remark about how beautiful they are and how "real" they sound.

-- Jim
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: chrisby on 21 Jul 2009, 05:54 pm
Chris,  Thanks for poking your head in here and I sure hope we hear more from you.




as my wife would say - careful what you wish for


Quote

Well, to my mind, Michael has hit the nail on the head, and absolutely beautifully.  But he's another N.J. guy, so what do you expect :D.

I was going to bring up this topic in some guise, and maybe I will and will start it with Michael's quote.

Truth and beauty -- the audiophile's dilemna.  I know where I stand.



this of course could be a Pandora's box, and here's a few random thoughts on opening the lid:   

"you can't handle the truth" - (i.e. that there is no single one?

"beauty is in the eye (i.e. mind) of the beholder"

All sensory input is simply data until processed by that amazing piece of wet-ware inside our skulls. Some of the programming is genetically "hardwired" and for the most part universal and constant,  other is far more dependent on an individual's lifetime accumulated experience - which adds rather a considerable degree of variability.   


Every time I read the words truth and beauty in the same sentence, I'm reminded of my favorite family friendly Zappa lyric (there aren't too many of those on this album) :

Information is not knowledge
Knowledge is not wisdom
Wisdom is not truth
Truth is not beauty
Beauty is not love
Love is not music
Music is the best...
Wisdom is the domain of the wis
(which is extinct).
Beauty is a french phonetic corruption
Of a short cloth neck ornament currently in resurgence*

Hard to believe that was 30yrs ago - time to tune up the air guitar for another imaginary guitar solo



(* I still have pictures of the ridiculous brown & white polka dot bow tie and window pane linen wide flair pants I got married in)




Quote


Know anybody looking for some fonkensteens? :D  Love 'em an awful lot but really need to get with the higher efficiency thing.  You built one hell of a speaker here and people still remark about how beautiful they are and how "real" they sound.

-- Jim


PM sent on the last item
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: ejfud on 9 Apr 2012, 08:56 pm
Looks like I'm the new facilitator here. I have a few ideas on getting more traffic here, but welcome anything you all would like to see.

I've made the "Share pictures of your fullrange speakers thread" a sticky to keep it up top and so people just dropping in can have a look at some your very cool builds. I'll be adding a few more in the next few days. Please post in them as you see fit.

Thanks
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: Freo-1 on 9 Apr 2012, 09:04 pm
Looks like I'm the new facilitator here. I have a few ideas on getting more traffic here, but welcome anything you all would like to see.

I've made the "Share pictures of your fullrange speakers thread" a sticky to keep it up top and so people just dropping in can have a look at some your very cool builds. I'll be adding a few more in the next few days. Please post in them as you see fit.

Thanks

Thanks for taking the mantle. 

I'm curious about these speakers.  I've always stayed away from them, as I could not work out how  they cold provide full frequency reproduction in a balanced manner.

However, some of them must do a pretty good job, or people would not be using them.  So, look forward to getting educated on these types of speakers.

What are some recommendations for research?

Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: ejfud on 9 Apr 2012, 09:46 pm
Thanks for taking the mantle. 

I'm curious about these speakers.  I've always stayed away from them, as I could not work out how  they cold provide full frequency reproduction in a balanced manner.

However, some of them must do a pretty good job, or people would not be using them.  So, look forward to getting educated on these types of speakers.

What are some recommendations for research?

Thanks, should be fun. I've been messing with single drivers for years and love them.

Check out this thread for some ideas and search from there.

http://www.audiocircle.com/index.php?topic=76975.0
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: Chikoo on 30 Aug 2020, 09:33 pm
Grew up listening to Philips 8” full range drivers with a whizzer cone. Every music system with a crossover seems to be missing something somewhere or emphasizes some frequencies over others.
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: Bendingwave on 31 Aug 2020, 03:06 am
DML's utilizing a single full range exciter with a response anywhere from 40-100hz for the low end and 14-20khz on the top end.
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: Ixnay on 17 Sep 2020, 01:34 am
  For about 10 years now, I have been using single driver speakers, wanting just to get a point source down pat. Yah, I know open baffle isn't all like that, and yet OB was good enough for me, until... I found that mounting a full range driver in a horn design would get me closer to bass that I like to hear. Enter the Mark Audio 12P. I quit testing different drivers right after hearing it. Ok, and bass should be there because of the horn design, right? Well, almost. Yes so close, so I hooked up a passive sub and powered it with a class D amp. Another yes and no for me. It's mostly about integration, but in some things I am not a patient man, so then, maybe as early as Friday, I have a 12" servo sub arrangement from Rythmik Audio that may be the ticket. The amp that comes with the driver has easier adjustment than the Velodyne SMS-1 unit that I use now to correct for room bass imbalance and so forth. In fact, it is supposed to be automatic, BUT I want what I want. Yes, you can do all that with the Velodyne, but knobs and switches are better for my brain than programming on the TV screen (that's the way the SMS-1 can be set up).
  To my ears the simpler the setup, the more I like it. That's what drove to single driver speakers to begin with.
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: JLM on 17 Sep 2020, 11:14 am
There is no perfect loudspeaker.  There I said/wrote it.  Single driver designs, like any other, offer pluses and minuses.  Coherence, efficiency, and no stinking crossover but at the price of limited frequency range, etc.

I commissioned single driver loudspeakers from Bob Brines 16 years ago: transmission line floor standers that use the "mighty" Fostex F200 driver (AlNiCo, magnet, rated 30-20,000 Hz, 8 ohms, 89 dB/w/m, 8 inch diameter with no whizzer cone, $575 each when last available).  Very smooth and full bodied with good detail but of course they "beam" above say 4,000 Hz and like any loudspeaker cannot by themselves address inherent in-room bass peaks/dips.  Note that I have a nice room: dedicated; 8ft x 13ft x 21ft; insulated; possibly over-treated; use Dirac room correction.  I listen mid-field (about 6.5ft away).  And I follow the loudspeaker/room interaction and loudspeaker measuring/testing teachings of Floyd Toole.

So over the years I've modded Bob's creations.  Added three carefully placed subwoofers to help address bass peaks/dips.  Removed the baffle step circuit to add to the purist creds and replaced with room correction.  And added "Late Ceiling Splash" ambience tweeters ala Duke LeJeune that sit on the floor behind the loudspeakers and are aimed directly upwards which help augment the highs and actually enlarge the soundstage so that the loudspeakers now sit 10ft apart without the centerstage sound stage collapsing.  The tweeters are basic Dayton Audio 1 1/8 inch soft domes connected in parallel with the F200a's with a resistor in series.

All this hardly follows the mantra of simplicity, but the resulting sound is most satisfying.  At least the rest of my system is simple: a NAD M10 "streaming amplifier"; a small one box yet highly flexible solution that is easy to use. 
Title: Re: Welcome to the new Single driver, Wide-bandwidth speaker circle
Post by: Ixnay on 17 Sep 2020, 06:22 pm
JLM,
  I took a look at your system page and yes, that is the biggest reason that you can enjoy your system. It is the room. Nicely done, and yes, it will have some sonic issues to be addressed, but due to prior planning, many of the harder issues are dealt with.
 Simplicity doesn't always stand by itself if confronted with room nodes and the rest, so perhaps it is better to say simple as can be without excess. There does come a point where over processing becomes a plastic image that does not work. The psyco-acoustics involved are pretty funny to me. The brain will accept some kinds of errors yet other errors are taken too seriously.
 To put my thought together I will say that if satisfaction is the goal, attempt at flatness is only the first step in the path, likely to veer off in a direction that satisfies us as individuals, not machines.