OK...So What The heck Should I Do With These?

[chromenuts]

I'm an incurable lurker on here who really hasn't learned enough yet. I spend A LOT of time reading about other people's experiments with different driver's and enclosures while I haven't finished my first set of speakers (Solo 103s with a pair of Fostex 107Es I got on clearance at Madisound).

Anywaaaaayyy...wifey sits and pretends she can tolerate listening to a lot of my obsessive audio related blah blah blah and is sweet enough to buy me a gift certificate to Madisound for Xmas and some Aurasound speakers they had on clearance that I was sort of ranting about.

Unfortunately the ones I had read about ( NS4-255-8A and NS4-194-8A) that others were talking of experimenting with in the Frugalhorn MK3 or other designs were sold out already. So Madisound said they would send her something similar.

I ended up with 8 of these:

https://www.madisound.com/store/prod...oducts_id=8993

I'm posting here since these speakers are technically listed and sold as full range drivers.

It doesn't make sense to send them back. Soooo...even though I can't design speakers and barely understand anything about T/S parameters, I think any of the BLH enclosures I was interested in experimenting with are not applicable here. Mainly because the T/S parameters of the speaker used in those designs appear to be completely different from these speakers.

My original plan was that I would eventually build a few sets of full range speakers that I could eventually use to experiment with a Home Theatre system...I'm still living with a stereo system and it gave me an excuse to build more than one set of speakers I thought the Solos I'm building might be flipped on their sides and used as a center channel along with some horn enclosures for the 206Es I have waiting on a shelf, and something different for the rear speakers (maybe Vampyrs, Frugals or who knows what). The idea was to start small and work up to the bigger more complex designs.

My first impression of these little speakers is that they might be nice used for a smaller set of HT speakers. Something that might migrate from the living room to the bedroom eventually? Maybe paired two per cabinet, if that is even possible? But perhaps they need a tweeter since the data sheet says they're only really good up to 10kHz if I understand it correctly?

I like the sound of the MTM type cabinets that are incorporated into my old KEF 104/2s very much. Mimicking that design might be interesting if these little drivers would be lacking by themselves in some kind of HT system.

I did a simple check on the HIFi Speaker Design website. They have a calculator that recommends enclosure types based on Fs and Qes data and the calculator there says these speakers are better suited for a vented enclosure. Having to vent the enclosure might make it difficult to maintain a perfectly symetrical design which I hoped might be possible so that a fifth speaker could be flipped on its side as a center channel.

I am not sure pursuing an MTM is advisable since I thought I read somewhere on Zaph's website or elsewhere that flipping an MTM on its side for HT use wasn't a good idea, maybe because the tweeter in his design was offset from the center line of the speaker? I can't remember now, or find the reference again.

I might have to come up with something else for a center channel anyway as I don't have a fifth pair of these right now. I have already eyed a cheap 8" driver for a band pass subwoofer box on sale if I do decide to go ahead with a HT system with these.

So how about it? Feedback, suggestions, designs? Happy Holidays!!!

[6L6]

With a Fs of 130hz you will NEVER get any useful bass from those drivers.

Put 4 of them in a .3ft sealed box, wired for 4 Ohm, make a stereo pair. Get subwoofer. Hook up. Enjoy!!







.
P.S. the link works fine.

[chromenuts]

LOL...yeah, it took me like four trys to get it right...just kept putting in a reason since I thought the moderators wanted one. It wasn't allowing me to just cut and paste the page info from my browser without messing the link up with quotation marks and the like.

Yeah, I wasn't expecting any bass from these really. The data sheet didn"t seem similar at all to some of the Fostex drivers that tend to work well in the BLH designs I've spent time reading about even to my completely inexperienced eyes and mind.

Why would they work much better four to a cabinet rather than just two? It would be nicer to come up with a way to get the four cabinets out of the total of eight drivers I got so I could play with the HT idea as I mentioned.

Thanks for the feedback.

P.S. Are you thinking along the lines of a small line array?

[6L6]

You could use 2 per box. It would also be 8ohm! About .2ft sealed. I suggested 4 in a box to keep the amount of woodworking down and the efficiency up...

If you do use 4 in a box, making a 'square' of drivers will have far less combing problems than a row. A row of 4 on it's side is about the worst arrangement.

2 in a box right next to each other is a good way to proceed.

[adason]

looking at the fr response, they would be good midrange from 200 Hz to 2 kHz
anything above is problematic, anything below is too low
I suggest use 4 per side with one high quality tweeter with matching efficiency
use with subwoofer, something similar to this, just the other way around, open baffle mid, closed box on woofer
DNA Sequence Speakers dipole open baffle woofer high efficiency point source array midrange tweeter treble loudspeaker

[chromenuts]

Wow...that is a wonderful looking design. It makes me want to try and get enough drivers to be able to do an entire HT system with all the speakers like that.

It does seem like they go through a lot of expense and time to get it to work right with the crossover network though. I wonder what kind of results I could expect with these cheap little drivers without being able to afford anything other than moderately priced components for a passive network?

Another question I have is why would you recommend reversing the cabinet design so the mids are open baffle and the sub sealed?

I noticed there's no specific recommendation of enclosure type on the Madisound site or the data sheet I was able to get.

Any recommendations for a tweeter to match these if I did go this route with these?

[6L6]

The way the mids are arranged on that DNA speaker are similar to how I would put 4 in a box... Probably not that far apart, however. Get them close, use a small tweeter if you happen to have something at hand (or not) and call it a day.

[adason]

"Another question I have is why would you recommend reversing the cabinet design so the mids are open baffle and the sub sealed?"

once you will hear good open baffle midrange, you will not want to listen to boxy sound
no matter how you construct the box, rear wave will bounce back and affect the membrane again smearing the sound, especially if the rear wall is so close
frankly I do not see why they did not make it open baffle mids in a first place when they went to the trouble making it open baffle bass
to achieve deep open baffle bass is not easy...possible, but not easy hence I recommend to you start with open baffle on mids, since you only need 200 Hz and go for closed box on bass
read everything there is on dick olsher pages about basszilla
and when it comes to the tweeter, there are limitless possibilities
good luck

[Cal Weldon]

Originally Posted by adason

once you will hear good open baffle midrange, you will not want to listen to boxy sound

[chromenuts]

Originally Posted by 6L6

The way the mids are arranged on that DNA speaker are similar to how I would put 4 in a box... Probably not that far apart, however. Get them close, use a small tweeter if you happen to have something at hand (or not) and call it a day.

What is the science to the actual arrangement on the DNA speakers? The mids are obviously positioned around the tweeter as a center point, yet they are not stacked over each other or laid out in a symmetrical diamond pattern. Does this also help with the combing issue that was mentioned? or does it address something else?

I have some Vifa DX25 tweeters lying around that were purchased in the event that my KEF speakers required replacements. That's about it.

I was trying to figure out how to calculate the efficiency of the speakers I have using the reference efficiency calculator on the HiFi Speaker site. I'm not sure I am using the right type of calculator or entering the correct data. I used the RMS(Pe) data of 20 watts for the first field and came up with .19 as a reference efficiency for these Aurasound speakers. Is this the correct figure when one refers to the speaker's efficiency?