Lazy Sunday TL computer speaker

[kraigo]

Based on Paul Carmody's Sprite and Murphy's corner line array, I've developed a little "thing" about the Dayton ND90-8. I've been toying with the idea of building a pair of computer speakers out of them in a transmission line. A single full range driver with Paul's filter. Simple and quick is the idea. This simple little calculator http://www.mh-audio.nl/Calculators/TML.html would probably do the trick, but if anyone else has access to Martin King's software and would like to embellish the concept, well, that's what this thread is for! Simple, quick, cheap. Not fantastic SPLs, but F3 in high 40Hz - low 50 Hz range should be achievable. Peeking over a computer monitor is the idea. The driver is here: https://www.parts-express.com/Dayton...iver-8-290-210

I hope someone is interested in playing this little thought exercise. If not I'll build the simple calculator version. Either way, it should be fun!

[kraigo]

Probably implied, but efficient use of a 24" x 48" handy panel would be appreciated. I'm planning on 1/2" thick as void free as Home Depot makes them.

[davidB]

Size of the monitor? And, how far away do you sit?

[djg]

You could do a lot worse than just building this little gem. "Noted designer".

http://projectgallery.parts-express....rized/mini-tl/

https://techtalk.parts-express.com/f...326935-mini-tl

[kraigo]

Roughly 24" tall speaker to get over my 27" monitors, roughly 48" from the speakers.

[kraigo]

Looking at djg's links - that kind of defeats the "simple" part of the original post.

[djg]

Chris Roemer has a "simple" ND design, ask him about it.

[kraigo]

Part of me is thinking of four feet of 4" PVC pipe per speaker. It would likely work,

[kraigo]

DJG - your link was really right on the money, but I want a single full range with simple woodwork. Good job!

[djg]

That's ok. Really though, check out Chris Roemer's ND desktop design, it may be more what you desire.

Paul K is the member here who has helped many with transmission line designs. I can't really volunteer his services though.

[kraigo]

Pico Neo. Found it!. Thx. Initial thoughts are that it's not what I'm looking for, but good information none the less.

[andy19191]

I hope someone is interested in playing this little thought exercise. If not I'll build the simple calculator version. Either way, it should be fun!

I too am working on a modest cost desktop TL but embracing the complexity for interest/fun rather than seeking to avoid it (the low cost comes from trying to use drivers I already own). The online software you link to makes some pretty crude assumptions and omits some relevant physics. Is simplicity your reasoning for not going with the more commonly used and capable hornresp software? Ditto for not tapering and/or offsetting? Not intending to criticise just seeking where interests may or may not overlap.

[kraigo]

I've never learned to use HornResp (although I have it). My shining light is the Frugal Horn, but the woodwork is more complicated than want to deal with (plus the size). It's really just the "spend the weekend playing with it and see how it sounds" aspect. Quite possibly they'd play for a weekend, get the electronics pulled and the boxes burned. It's the "what would that sound like" aspect, but if Paul K. were inclined to get involved I might go beyond a week and Firewood thought.

Just a quick and easy listening experiment.

[andy19191]

My inspiration was a small floorstanding Daline TL I built in the 70s which was designed to be placed flat against a wall and used sealed cavity coupled to a tapered line. Not sure I will keep the combination of cavity + line and would like to explore a number of acoustic alternatives for suppressing the first unwanted reflection which was not included in the original design. The opposite of a quick easy listening experiment involving not only a long design study but possibly writing some simulation software.

[kraigo]

OK, so let's be more precise: I'm looking for a single fold to keep the height at around 24" or slightly more to peek over monitors and front ported because I know damned well that they will be slammed against a wall. Make up in height what you would get in depth, keep the top closed because, you know, drinks. I think the marketers would describe this as a "Lifestyle Speaker".

[kraigo]

FWIW, a variation on Chris' Pico Neo's is winning out. Slightly different dimensions and perhaps some filters to smooth it a bit more. I'd love to try the TL, but the bass reflex is easier for me to model at this point. The Sprite is attractive, but I have a decent boom box (Phillips - decent, not great) that I bought when I was getting cataract surgery and it has proven sufficient for now.

I have four ND90-8's. The TL isn't ruled out, but I can do both. My "Pico Neo" models at F3 of a little shy of 45 Hz, which is (to my mind) fairly reasonable for a speaker that small and I have a reasonable number of links for filters (starting with the Sprite) to try to tame it a bit while keeping to a full range/single driver system, which is what I'm interested in with this project.

I still love the idea of a smallish Frugal Horn though.