A welcome to the single driver speaker circle

jrebman · « **on:** 9 Sep 2007, 10:27 pm »

My name is Jim and I am the facilatator for this new, but apparently long overdue circle. I'm quite new at this facilitator thing so bear with me as I learn the ropes.

I wanted to start this circle because I have a deep curiosity and fascination with the subjects of single driver speakers and single-ended amps and I know many others do as well.

The demand for products in this market seems to have brought it more into the audio mainstream and with everybody from DIY enthusiasts to seasoned audiophiles jumping in to experience what it's all about.

This will be a place to share experiences, knowledge, and questions. All are welcome from novices to experts, from manufacturers and designers and DIY enthusiasts.

The only thing I really request is that everybody who comes here -- whether a fan of SD speakers, or not -- is that we all keep in mind that everybody has different ears, tastes, rooms, preferred musical genres, etc. and that any disagreement be cordial and respectful of the other person's point of view. And of course, the usual AC rules about no religion or politics.

So again, welcome, and let's have fun!

-- Jim

Bob in St. Louis · « **Reply #1 on:** 10 Sep 2007, 12:52 pm »

Welcome to the club Jim, and congratulations on your promotion and new duties.

I'm honored to be the first to post in your new forum.

I have a few questions for you:
- Is a coaxial considered a single driver? Or is that called "cheating" by the SD purists?
- What, by true definition of "Single Driver" are it's responsibilities in the frequency spectrum? Are they allowed augmentation?

Bob

Scott F. · « **Reply #2 on:** 10 Sep 2007, 02:38 pm »

Very cool, we now have a single driver Circle

Bob, by exact interpretation, a single driver is just that, a sole driver that handles all duties from low bass to extreme treble. Coaxials are considered point source or dual concentric drivers. Augmentation of the bass with a sub sort of redefines the single driver as a wide range driver. Both of these methods, though not purist in their form, seem to acceptable for most single driver guys. Don't forget, back loaded horns, like Ed's Horn Shoppe speakers fall under the single driver category too.

On the true single driver front, there are a number of designs that can get pretty close to covering all but two octaves (the lowest and upper most octave). Their main attraction is coherence. If you remember the sound of my big system, especially through the midrange and treble regions, it is pretty darned seamless. There is a purity of signal that tends to be lost (in single driver fan opinions) when you place a crossover in the signal path. Then you get into timbre mismatches between multiple drivers. Not saying that all multi-way speakers suffer this fate, its just that single driver speakers avoid it.

If you want to hear one of the best, true, single driver speakers I've run across, plan on coming out (again) sometime after the 29th. I've got the Teresonics loaded with the Lowther PM2T's (Ticonal magnet)(I've also got some PM2C's sitting in the wings). Right now I have them off to the side as I've got the Altec A7's in the Redrum. I'd like to leave those up and running for the 29th (I think). The Teresonics really need corner loading and the Altecs are there right now, plus they are an unbelievable pain to move since they are so big and heavy. After the 29th, we could move them out and set up the Teresonics again. When (Bolder) Wayne came by a few weeks ago, he mentioned that these were the best single driver speaker he had ever heard.

Bottom line is single drivers can be loads of fun to play with and listen to. Depending on the driver chosen, you can get some pretty darned good sound out of them. Sure, there are compromises just as in every other speaker design but single driver fans choose their shortcomings over the conventional speakers shortcomings.

DaveC113 · « **Reply #3 on:** 10 Sep 2007, 02:49 pm »

Jim,

Congrats on the new circle! I am a new SD convert, I believe the value for the money can't be beat. I own Omega XRS, and listened to the Omega Maxhemps recently, which completely exceeded my expectations. They are now on the top of the list to replace the XRS when I get a bigger space, and are among the best speakers I have heard at any price.

Bob, I don't think a coax is a single driver because it requires a crossover. Single drivers are crossoverless, point source, and time and phase correct throughout much of the audio band. Single drivers can't quite cover the frequency spectrum, but close. Many try to find the best way to add a supertweeter or sub to the mix, or both. Zu speakers are an example that do both, and Omega just came out with a subwoofer to match their products. The Omega Maxhemps go down to the mid 30s, they are very close to a full range speaker.

For me, single drivers are fun to listen to, they draw you into the music and make it easy to forgive whatever shortcomings they have.

Dave

jrebman · « **Reply #4 on:** 10 Sep 2007, 03:17 pm »

Bob and Scott,

Thanks being the the first to post and for bringing up just the things I hoped we would start with.

I honestly don't know how to define a single driver speaker, or maybe I'm reluctant to define the scope of this forum so rigidly that it ends up being for purists only. My hope is that we will figure this out as a community and not lock us into a strict interpretation that leaves no room for creative, out of the box thinking.

Coaxials, super tweeters, systems augmented with subs, etc., I think are all things that some people feel are truly legitimate single driver speakers, as long as the main driver is handling the largest chunk of the spectrum, or most of the musical information -- often defined as between 80-200 through 10-20kHz -- and that's not carved in stone either. What about OBs that have two identical drivers in a 1.5 way crossover arrangement? There we have two drivers of roughly the same specification, but with the load apportioned to give each driver a little less to deal with.

I don't know -- I'm asking for people to weigh in.

My feeling is that all the various speaker types -- front and rear loaded horns, open baffles, quarter wave pipes, MLTL, and traditional box speakers with sealed, bass reflex, and aperiodic alignments are all candidates for discussion as long as they are within the "spirit" of the single driver approach. Maybe it would just be easier to say what is not considered appropriate -- speaker systems of any configuration where there are multiple drivers that cover limited parts of the spectrum, and who have musical energy apportioned to them by the use of complex -- whether active or passive -- crossovers. So, a speaker like the Zu Def. Pros, for example -- the main driver can be driven by a 2 watt SET amp and cover the vast majority of the spectrum, and the lower end (don't know exactly what the cutoff frequency is) is handled by a large SS amp. To me, this seems to be well within the spirit of single driver-dom, and on the other hand, I can see where some may disagree. My hope is that there will be room here for both.

Enough said for now -- let's hear what others have to say.

-- Jim

miklorsmith · « **Reply #5 on:** 10 Sep 2007, 03:23 pm »

Funny you should mention the Pro's! I was reading the first nuggets of this excellent idea of a Circle and chuckling to myself that I own probably the most convoluted design that could even make a "single driver" claim with a straight face.

I arrived here after building the TNT Big Fun Box and seeing the possibilities though. I just received a pair of Omega's first run hemp drivers to replace the Fostex 206s in those boxes and that promises to be excellent. I'll have to bi-amp those bad boys with the sub array from the Pros in the main system and see how that goes.

Yeah, it sounds weird. But, when I had the TacT I did exactly that with the Fostex drivers and Yamamoto amp on the BFBs and it was super. I even featured that combination as the kickoff to a listening event at my house.

Cool beans on the Circle, it's sure to be great!

jrebman · « **Reply #6 on:** 10 Sep 2007, 03:29 pm »

Dave,

Thanks for posting. I didn't see your post until after I had sent the last reply.

My guess is that there are going to be a variety of opinions on what constitutes a single driver speaker, and my intent is to let people define their own idea of what an SD speaker is, as long as it is within reason, which is to say that folks other than purists should be able to feel this is a place for them.

I've heard and liked both, and I think it's more a matter of implementation and how that works to your individual tastes and priorities.

Welcome,

Jim

MJK · « **Reply #7 on:** 10 Sep 2007, 03:33 pm »

Jim,

What do you mean by "complimentary amplifiers" in the circle description?

Thanks,

Martin

jrebman · « **Reply #8 on:** 10 Sep 2007, 03:44 pm »

Martin, Welcome, and I hope we'll see a lot of you around here

. The phrase complimentary amplification is again, an attempt to not limit this to only folks who prefer SET amps. I originally proposed the idea for this circle as a single driver/SET circle, but I know I have used my SD speakers with SET, SEP, PP, Digital, and chip amps, and they all, although very different, were enjoyable to listen to. So, I didn't want to limit to a type of amplifier, power level, etc., efficiency rating, or anything else that would limit this to the purist SET/SD approach.

Mike,

Believe it or not, it was no accident that the Def Pros were mentioned, because it was your system I had in mind with the big pro SS amp on the bottom end, and the very sweet Yammie, with all of 2 watts, delivering most of the musical loveliness

.

Thanks for posting!

-- Jim

DaveC113 · « **Reply #9 on:** 10 Sep 2007, 03:45 pm »

Yes, I agree as I'm using a sub with my single drivers.

Because there are no true full range single drivers there will be folks who want to augment them. I think its a good idea if it is accomplished in an unobtrusive manner... I guess the debate is whether or not this is possible. I don't have enough experience with a supertweeter to comment, but a very fast, musical sub with low distortion that is crossed over at a fairly low frequency seems to work well.

Dave

mcgsxr · « **Reply #10 on:** 10 Sep 2007, 03:48 pm »

Looks like another great circle on AC, an excellent complimentary one to the OB circle I try to help keep running well.

I fall into the "wide band" driver user, as I do use subs. Visaton b200 mains, and Mach5Audio 12's for the bass.

Great circle, all the best,

Scott F. · « **Reply #11 on:** 10 Sep 2007, 03:51 pm »

Jim,

Maybe a good guideline is to set a somewhat loose definition of the single driver speaker to be more along the lines of a wide range driver. A speaker that covers as a minimum of say 80Hz on the low end and at least 8k on the high end. That pretty much covers most of what the single driver guys consider purist but also allows some variations for bass augmentation and super tweeters.

miklorsmith · « **Reply #12 on:** 10 Sep 2007, 03:56 pm »

Scott, I concur, because I qualify! (if barely)

Scott F. · « **Reply #13 on:** 10 Sep 2007, 03:58 pm »

Quote from: miklorsmith on 10 Sep 2007, 03:56 pm

Scott, I concur, because I qualify! (if barely)

Me too

gbeard · « **Reply #14 on:** 10 Sep 2007, 04:03 pm »

I've rarely qualified for anything...But my Omega Superhemps fit the bill on this circle!

Cheers!

gb

Scott F. · « **Reply #15 on:** 10 Sep 2007, 04:05 pm »

Gary, you're back

Welcome

jrebman · « **Reply #16 on:** 10 Sep 2007, 04:06 pm »

Scott,

Really, I think that was the point I was trying to get across and for some reason the term "wideband" had temporarily vanished from my vocabulary

In one iteration of the tagline for this circle, that was a word I used.

Anyway, you guys have a hell of a lot more experience than I so hopefully you'll help keep me on track in this new venture

.

-- Jim

MJK · « **Reply #17 on:** 10 Sep 2007, 04:25 pm »

Quote from: Scott F. on 10 Sep 2007, 03:51 pm

Jim,

Maybe a good guideline is to set a somewhat loose definition of the single driver speaker to be more along the lines of a wide range driver. A speaker that covers as a minimum of say 80Hz on the low end and at least 8k on the high end. That pretty much covers most of what the single driver guys consider purist but also allows some variations for bass augmentation and super tweeters.

I guess I don't qualify. My current design and my new designs are not even close to meeting the 80 Hz value.

lonewolfny42 · « **Reply #18 on:** 10 Sep 2007, 04:57 pm »

Good luck Jim....looking forward to gaining more knowledge about single driver speakers.....

Chris

zacster · « **Reply #19 on:** 10 Sep 2007, 04:58 pm »

Just don't build 'em out of cardboard.