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I think I might want new speakers.

As I said in my intro (a year ago), I am not an engineer. More of a general tinkerer. I started rebuilding speaker crossovers when I was a kid, and built my Bottlehead Stereomour amp from a kit, so I understand the basic concepts but I have no illusions about my ability to design a new speaker or amplifier from scratch. My current speakers are homages to one of the Omega Outlaws:

https://omegaloudspeakers.com/collectio ... 2295842892

Mine use Fostex 120a (driven by the Stereomour, with a cap to roll it off at 300hz) and a Dayton 8" sub driven by a Crown 1500 XRS (digitally crossed over at 200hz). They are the closest I've come to my own design, but are simply based on the TS parameters of each driver so aren't very sophisticated. No baffle step compensation or the like. I think they sound pretty good, but have some of the shout and high-volume breakup inherent to many full-rangers of this size. They also seem to lack the mid-range richness that I've heard from larger drivers. The question is, are my speakers the problem, or something else in my system? The rest of it consists of:

AES AE3 Preamp
Lampizator Amber Plus DAC
ProJect Debut Carbon with Shure M97xe
Bellari phono pre
Braided silver/teflon interconnects

Sadly I missed CAF once again, so I can't easily sample different configurations. Is another local meetup scheduled any time soon? If so, do people bring their stuff to review with the group? If not, I could host one in Takoma Park, but only for a few people as my house is small.

That last bit reminds me of some important limitations:
My listening room is only about 10 feet deep, so the speakers have to be very close to the front wall. They also can't be super wide. I recently tried some old Zenith 12" drivers in an OB that was 36" high x 16" wide with 12" wings on either side. The WAF was rather low on those, and the sound wasn't that great, so back to the basement they went. I attached a pic of my current scene for perspective.



I've been looking around at some kits that might match my needs. Troels Gravesen has a few that use his Jantzen 8008 driver that look promising, as does the Humble Homemade HiFi Plutone, but I gotta think I can find something just as nice for less money. Bottlehead also has a new speaker kit called the Jager, but it comes with a cabinet flat-pack. As woodworking is another hobby of mine I don't want to pay someone else to make boxes and cut holes when I can do that myself.

So, any thoughts?

Would anyone like to come sit on my couch, drink my beer, and criticize my system? Perhaps bringing some interconnects, speakers or an amp to substitute in?

Thanks!

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Walt

Have you considered the following -

https://www.madisoundspeakerstore.com/4 ... 4-way-kit/

The kit does not include the crossovers which need to be electronic (analog) or digital dsp and 8 channels of power amplification are needed but you do all the woodworking.

For crossovers see -

http://www.linkwitzlab.com/LX521/DSP_challenge.htm

If I were doing it I would use Richard Taylors approach with 8 channels of DAC such as the Xonar Essence STX II 7.1 card which one of the members has experience with. Another possibility for the software if you are running Windows (I do linux) is -

http://www.thuneau.com/allocator.htm

Anything that's a dipole isn't going to work well close to the wall, there's no getting around that. Since that's a requirement in your room, it's time to think about other options. It's quite a coincidence that I was thinking just the other day about what it would take to design a speaker that sounded "right" when it was ON the wall. As far as existing designs, there are a plethora of back-loaded horn designs for full-range drivers out there, including some unique designs such as this: http://6moons.com/audioreviews/cornu/cornu.html

Roscoe

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I can explain it to you, but I can’t understand it for you.

You might also consider a TQWP/TQWT design. I've got a pair of the Dayton PS-220s (I think that's the right number) TWQPs in the home theatre, and they do quite nicely. You're welcome to come out and hear them sometime, I can easily put them in the main system.



Roscoe

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I can explain it to you, but I can’t understand it for you.

There is vary long thread on building a Cornu spiral using inexpensive foam board at

http://www.diyaudio.com/forums/full-range/225622-building-cornu-spiral-horn.html

One of the main contributors to the thread, XRK971, lives in the DC area so you might get some ideas from him. He has a lot of experience building various enclosures out of foam board. I haven't tried it, but the technique is supposed to be cheap, quick and simple and deliver surprisingly good results.

ray

Hi Walt

Thanks for your response. I chose the F120a due to their reputation as being very smooth while having pretty good high-frequency extension. They aren't overly bright at all, just sometimes a little glare in the upper mids shines through. I honestly don't know if it is due to poor recordings, my enclosures, or the drivers themselves. Certain recordings don't have even a trace, while others have more than I can happily handle. You might be right, of course, and I am certainly interested in hearing other 5" drivers to see if they are superior.

Does anyone have a 5" extended-range driver setup I could put my ears on?

I heard a larger Voxativ recently at Urban Hifi in Takoma Park. It was an Ampeggio Signature and quite amazing, but even it had some of the same characteristics that my Foxtex has. I suspect there is only so much a single driver can do, even one that costs more than my car.

I actually saw that yesterday for the first time.

It is a far cry from the SET/single-driver/minimal crossover approach I've been following of late. That isn't to say that I'm not interested, but it would be a huge departure and would definitely require a listen before committing to such a project.

Then there is the point Roscoe made regarding my room. I don't think dipole speakers are designed to be quite as close to the front wall as I need to keep mine. As of now, the front baffle of my speakers are no more than 15" from the wall, with the rear of the speaker only a couple inches.

3' minimum, 4'+ even better... The problem is the ear-brain combination. Once you get the dipole >3' from the wall, the time delay is long enough that the ear/brain combination is smart enough to tell that the reflected sound is actually a reflection and "filter" the reflection out. With <3' the reflection is heard as a smearing of the direct sound.

Roscoe

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I can explain it to you, but I can’t understand it for you.

What a cool idea!

I don't know if it would work in my space, but I'm certainly intrigued. Thanks for the link. I'll give it a read.