Single Driver Speakers

[psbfan9]

I've been reading about single driver, no cross over speakers and wanted to know if anyone has experience with this type of speaker and what others think about this design.
I'm wondering if these require a good bit of work to get them properly placed. Do they have a small sweet spot? Seems the bass would be good, what about the highs and mids?

Thoughts? Experiences?

 

[Dennis Murphy]

First of all, any single driver speaker that doesn't include a baffle step compensation circuit will sound too forward and shouty in the midrange. So there will be crossover components (a resistor and a capacitor) if not a crossover per se. Second, most "full range" drivers have ugly breakup modes at the high end, and this will mean irritating highs unless dealth with using additonal components. Third, even the best drivers will not work well at normal listening distances because the highs will beam, and the sweet spot will be extremely narrow. The designer and manufacturer of the most advanced and expensive full range driver asked me to design a monitor for the American market a few years ago, and I worked and worked with that thing. Although it was an adimirable technological achievement, it still sounded closed-in when compared with about any competent 2-way with a real tweeter. And I couldn't hear any advantage from the phase coherency of the single driver. The imaging wasn't any better and the soundstage wasn't any deeper. That said, a well engineered single driver (with baffle step compensation and a trap circuit to tame the highs) can sound very nice in nearfield listening. I designed a full range speaker for Jim Salk using a Tang Band full range driver that made an excellent computer speaker. Even then, however, it sounded better when we added a very small tweeter to handle the highest frequencies.

 

[ski2xblack]

Very thorough summation by Dennis. As a user of oddball amps, I've tried, really, really tried, to give the single driver approach the benefit of the doubt. I've heard probably a dozen or so different takes, and DM's excellent expose could be a perfect description of the problems I heard first hand. I would grant them more positives than Dennis, as they do often have a peculiar immediacy and presence to my ears, but so do horns and planars. I find them so compromised in other areas that I value (such as dynamic range, bass, an even-keeled response in the upper registers, and better coverage/power response out in the room) that I prefer other approaches. I wouldn't say avoid at all costs, but realize the territory and assess your situation before spending any money. Go to AXPONA or RMAF and get ears on some examples.

 

[lsiberian]

I've looked at full range speakers designs and I really don't see the benefit. Even the Jordan Watts drivers don't exactly get high volumes.

You could consider the Loki coaxial kit from madisound. TLS uses one for his center.

 

[Dennis Murphy]

Very thorough summation by Dennis. As a user of oddball amps, I've tried, really, really tried, to give the single driver approach the benefit of the doubt. I've heard probably a dozen or so different takes, and DM's excellent expose could be a perfect description of the problems I heard first hand. I would grant them more positives than Dennis, as they do often have a peculiar immediacy and presence to my ears, but so do horns and planars. I find them so compromised in other areas that I value (such as dynamic range, bass, an even-keeled response in the upper registers, and better coverage/power response out in the room) that I prefer other approaches. I wouldn't say avoid at all costs, but realize the territory and assess your situation before spending any money. Go to AXPONA or RMAF and get ears on some examples.

Thanks--glad to see I'm not a minority of one. Some people really swear by these puppies. I usually swear at them. One correction, though. I meant to say that the components in a baffle step compensation circuit would be an inductor and a resistor. A cap and resistor will give you impedance compensation.

 

[JerryLove]

First of all, any single driver speaker that doesn't include a baffle step compensation circuit will sound too forward and shouty in the midrange.

Unless it's omnipolar, or uses a mechanical crossover that has a similar effect. This was not a problem with my Walsh Ohm F's

 

[Dennis Murphy]

Unless it's omnipolar, or uses a mechanical crossover that h
as a similar effect. This was not a problem with my Walsh Ohm F's

Right, although I'm not sure what you mean by a "mechanical" crossover. And the whole point of a single driver speaker is to eliminate any crossover.

 

[JerryLove]

The single cone on the F used differing materials, thicknesses, and cuts to limit wave propagation by frequency to portions of the cone.

As I understand it: a whizzer serves a similar function; reproducing only a portion of the audio being fed to the speaker.

I don't know that there is a single reason that people will use single-driver speakers; and I believe that it is the effect of the crossover (particularly in terms of phase shift) not the presence of the crossover, that some wish to avoid. I don't believe that either of the above described was of mechanically controlling which parts of a driver produce which frequencies introduce phase shift, though I could be wrong (personally, I think phase is less important than literal time... but I digress).

For some though: it's the appeal of a single point-source, or the perception that more uniform (relative between frequencies at a given angle, not relative between angles) off-axis performance can be had from a single driver.

I personally remain a fan of multi-driver configurations.

 

[Dennis Murphy]

Yeah--I'm not sure what a whizzer does to phase. There probably isn't a single answer to that. anyhow, the best treatment for a whizzer is a sharp knife. You can get a point source with a well-excecuted coaxial, so I really think the primary fascination with single driver speakers is phase, and maybe a fear that any crossover will mess up the response. It's certainly true that a good single driver design will sound less colored than a bad 2-way or 3-way.

 

[Pyrrho]

Unless it's omnipolar, or uses a mechanical crossover that has a similar effect. This was not a problem with my Walsh Ohm F's

There is another company doing a slightly different take on that concept:

German Physiks - High End Technology Loudspeaker Manufactur - DDD Driver - THE UNICORN MK II

I have not heard, or even seen one of these. I was interested in learning more, until I found out about the prices on their gear, and decided it did not matter for me what they sounded like, as they are too expensive for me.

 

[afterlife2]

TLS sent me a pair and will let you know by this weekend. I'm no expert so it will be kind of a naive overview of my thoughts.

 

[lsiberian]

There is another company doing a slightly different take on that concept:

German Physiks - High End Technology Loudspeaker Manufactur - DDD Driver - THE UNICORN MK II

I have not heard, or even seen one of these. I was interested in learning more, until I found out about the prices on their gear, and decided it did not matter for me what they sounded like, as they are too expensive for me.

Looks like an amazing speaker. It is definitely not for loud listening though.

 

[Dennis Murphy]

There is another company doing a slightly different take on that concept:

German Physiks - High End Technology Loudspeaker Manufactur - DDD Driver - THE UNICORN MK II

I have not heard, or even seen one of these. I was interested in learning more, until I found out about the prices on their gear, and decided it did not matter for me what they sounded like, as they are too expensive for me.

I heard this, or a smiliar model, at RMAF in October. It's not your standard one-driver design. I assume it's a refinement of the Walsh driver. Anyhow, it got my vote for best sound at the show. It does use a sub, so there's a crossover. But not in the midrange or treble.

 

[lsiberian]

I heard this, or a smiliar model, at RMAF in October. It's not your standard one-driver design. I assume it's a refinement of the Walsh driver. Anyhow, it got my vote for best sound at the show. It does use a sub, so there's a crossover. But not in the midrange or treble.

Is it a lot prettier in person?

 

[Pyrrho]

There is another company doing a slightly different take on that concept:

German Physiks - High End Technology Loudspeaker Manufactur - DDD Driver - THE UNICORN MK II

I have not heard, or even seen one of these. I was interested in learning more, until I found out about the prices on their gear, and decided it did not matter for me what they sounded like, as they are too expensive for me.

I heard this, or a smiliar model, at RMAF in October. It's not your standard one-driver design. I assume it's a refinement of the Walsh driver. Anyhow, it got my vote for best sound at the show. It does use a sub, so there's a crossover. But not in the midrange or treble.

Most of the German Physiks speakers are as you say, and use a conventional woofer for the deep bass, but not the Unicorn. The Unicorn, the model to which I provided a link, uses only one driver, so there is no crossover. However, it does use equalization, so it is not without additional circuitry; see link above.