Large Dual FLH with multiple ENabled FE126en drivers

[mberrync]

I am new to full range speakers but need more efficient ones for my Cary 805s. After reading on various sites about the merits and drawbacks of various drivers and speaker box designs I am interested in the idea of combining the Horneshoppe's Model 3 use of multiple FE126en drivers in the larger 11 3/4" wide Nagaoka style Sachiko dual front loaded horn. I would like a wide and tall soundstage along with clear imaging. I want to initially try to avoid adding a super tweeter or sub to augment the sound. I understand that using multiple drivers will increase overall efficiency but I have the following questions:

1. Will using 2 horizontally placed or a 4 square pattern of drivers lessen the wonderful imaging I read is created by single point full range drivers.
2. Will using (4) 4" FE126en drivers in place of one 8" driver work well in the Sachiko Dual FLH? What problems may it create?
3. Is there any issue with using Enabled drivers in a multiple pattern?
4. How important are exact dimensions in horn designs? Will fractions of an inch make a listenable difference in the sound?

I do plan on including a removeable/replaceable speaker baffle to be able to try out different combinations. I understand that it is the combination of the drivers and box that make it work.

[Scottmoose]

I'm just wondering what special advantages you are hoping to obtain using 4 drivers the cabinet was not designed for instead of one that it was? Briefly

1/ Possibly. Possibly not. It's likely going to end up being circumstance & taste dependant.

2/ Sachiko is a back horn, not a front horn. It does not load the front of the driver. And no, they're not likely to work all that well; I'd anticipate a relative lack of gain on the bottom end.

3/ I don't think anyone's tried it.

4/ Very, and they can do, yes.

Indeed. A cabinet is designed for a specific drive unit, so if you drop something else into it, it's not going to perform as originally intended.

[mberrync]

The reason for using the 4" sized drivers is that I have read they were the best balance between maintaning HF and still having enough LF. The reason for using 4 drivers would be (1) to achieve increased efficiency over the 93 db listed for the FE126en's, (2) to create a speaker with a large enough sound for a 28' x 22' room, and (3) be able to use the wider box which would be less likely to tip over.

On the Planet_10 website, the Spawn family plans page, the Sachiko is shown with the openings to the front of the speaker. I have assumed this was a front loaded design. There couold be other designs I don't know about.

If I was going to compare using a number of 4" drivers versus one 8" driver what parameters would I use to guide me? The surface area is very close to being the same but that is probably too simplistic. Obviously, actually building it and listening is the real test. I just want to be headed in the right direction for what I am attempting to accomplish.

[Scottmoose]

Well, they have their upsides WRT the HF, although that is tempered by their relative losses on the bottom end. Re your numbered points,

1/ You'll get +6dB over 1 FE126En using four drivers, assuming series-parallel wiring. That's theoretically a little more than 1 FE206E, although the efficiency of the 126 is in practice a little over-rated, so they'll be much of a muchness in that sense.
2/ You'd get that with the driver it was designed for in the first place
3/ Ditto.

No. A front horn is what it sounds like: a horn attached to the front of the driver. Sachiko is a back horn -the horn is attached to the rear of the driver. I happen to know this enclosure rather well because I designed it.

You'll need to have drivers with a similar total Q, combined Vas, Re and BxL similar to the design unit (Fostex FE206E) once you've accounted for the manner in which you wire them.

[chrisb]

of course you could always stack 4 smaller BLH (either rear or front mouth) - one pair side to side and the other pair flipped on top - that I know as been done

the most number of EnAbled FR drivers that I'm aware of being tried in a single enclosure was 2xFF85K in a stretched uFonken

as the oft raised "issues" of sensitivity and playing levels, perhaps it's my approaching 60yr old aesthetic, but just how freaking loud do you need to listen? and all theoretical calculations of clipping-free power required to achieve same aside, consider the following - courtesy of Sjaran Ebaen at moons

** A recent Swiss wine & cheese presentation by Nagra Audio, of their new 300p amplifier in a sizeable hall of Château d'Aigle with Verity Audio speakers, showed their amp's modulometer at 0.2-watt output with 2-watt peaks when playback levels of a Jacques Loussier Mozart Piano Concerto N°. 20 were just right. While Yamamoto's 3-watt rating does impose obvious restrictions in speaker choices, most consumers are sadly misinformed about their actual power requirements. Combine the A-010's circuit gain with a hi-gain source like my 5.5V-max Weiss DAC2 for example and you could do serious damage with even standard 90dB speakers and a passive preamp. Granted, loudness alone never equates with optimum drive and control. Particularly low-frequency peaks should cause clipping over most regular speakers whilst running a no-feedback SET to its power limits will seriously increase its harmonic distortion. Even so, common concerns that such amps can't play loud enough unless one had 110dB horns, tiny rooms or only played string quartet adagios are somewhat irrational.

of course none of the equipment he's referencing are DIY type or budget, but I kinda think the highlighted comments are applicable for much of our real world listening


If your speaker placement can accommodate a rear mouthed design, it might be worth taking a look at Scott's Valiant for the FE126En - one of the better enclosures of quite of few in which I've heard this driver





and there are lots of ways to keep a tall skinny speaker from tipping over

[Cal Weldon]

Originally Posted by chrisb

but just how freaking loud do you need to listen?

Ahem.

[chrisb]

Originally Posted by Cal Weldon

Ahem.

let's qualify that to add "and keep your hearing"

[Scottmoose]

True. That said, you can never have too much headroom However, if 4 x FE126En are required, then the horn really does need to be designed with this in mind, whether for 4 units, or individual horns then grouped together.

[Ty_Bower]

If you want to build Sachiko, you should use the 8" driver for which is was designed. If you want to use a 4" driver, you should build Saburo* instead. If you want twice as much output you should build two pair Saburo. You could probably construct two Saburo cabinets as Siamese twins, sharing a common center wall.


* or one of the newer spawn designs for the 4" drivers

[chrisb]

Originally Posted by Scottmoose

True. That said, you can never have too much headroom However, if 4 x FE126En are required, then the horn really does need to be designed with this in mind, whether for 4 units, or individual horns then grouped together.

why spend the time properly engineering a design when the hillbilly brute force approach can work well enough for many a refined listener?

meow

It would appear that mberrync may not yet have heard a commercial or DIY "fullrange" speaker with the FE126E (perhaps any?) driver. Until such time, it may be premature for him to assume that a single wouldn't be enough.


Of course, now that I more carefully read the thread, his room might well benefit from a well executed design for a single larger driver (such as the FE166) as opposed to multiples of smaller. Unless there are some serious placement restrictions not yet described, I'd guess that average listening distance could be far enough that integration of the dual front mouth designs, which applies for any size driver, wouldn't be a big problem.



The question of "scalability" of this type of speaker often arises, and while there's a lot more work involved in recalculating the math than in revising the material cut sheets, I've built / heard enough of Scott's designs to appreciate that he has a pretty good handle on the former, making it a lot easier for guys like me to accomplish the latter.