Bookshelf fullrange advice wanted

[Rocky]

Hello, I am seeking advice on some relatively small bookshelf speakers I plan as a birthday gift for my sister. She lives in a relatively small apartment with her fiance, and I don't think they have the floor or room space in the living room for floorstanding speakers. They are not audio freaks like myself, but both are professional musicians (he's a drummer, she plays viola) so they recognize good sound when they hear it.

The game plan is to replace the speakers already on the shelf (small cheap JVC models), so I will have to stay within 10-12 liter. I want a fullrange driver for that volume that can provide decent bass as well as HF, and as my sister is not into triode stuff, I don't see high efficiency as a must.

I have already had a good look on the Fostex F120A 5”, but they are a little on the expensive side. The candidates I'm considering seriously are Jordan JX92S and Fostex FX120 (love the appereance of this one), perhaps also the CSS FR125S. Any opinions on those drivers or others the same size for such an application?

 

[Godzilla]

Save the money and go for:

http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=264-846

or

http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=264-848

They work nicely in small sealed cabs... tweeters optional.

Godzilla

 

[Godzilla]

I keep posting twice by accident... grrrr....

I have the 4" TB Bamboo and it works great in a small sealed or ported box of the size you need. It will be a great upgrade but the treble might be very mild manored compared to what they currently have. If the speakers they have now have 'hot' tweeters it might take them a few listens to get used to the full range sound.

Peace,

Godzilla

 

[Rocky]

I've heard the TangBands have gotten quite a reputation in their price range, but I think that with those drivers I would have to experiment on my own before attempting to build good sounding speakers for others, and for that I am too busy with my own setup.

I have used Fostex's FE range of drivers in the past, before I ended up with compression drivers, horns, and DHTs, and they have much of what I am looking for except they need a huge BL horn or transmission line to get any bass, and the smaller FE drivers tend to get very muddy on complex music. I am thinking the FX120 will retain much of what I loved about my early Fostex speakers, not as efficient but with better low end extension in the modest space requirements of this project. So on closer thought, this is really a choice between the FX120 and the Jordan JX92.

 

[navin]

what about these

http://www.bestbuy.com/site/olspage...t&productCategoryId=cat03043&id=1138085354138

there is a thread with more info
http://www.diyaudio.com/forums/showthread.php?s=&threadid=81277

granted they are not fullrange but they work good.

 

[SunRa]

how about these ones?
http://www.supravox.fr/haut_parleurs/135_LB.htm

and

http://www.supravox.fr/haut_parleurs/165_LB.htm

...the second one i like more... and the supravox site has some bookshelf like enclosure plans for it...and it's cheaper than the jordans I believe..

 

[Rocky]

navin; At first glance, it doesn't look like what I want, but I'll have a closer look.

SunRa: Great speakers, Actually, I simulated exactly the two drivers you mention yesterday. Problem is, they sacrifice bass for efficiency, wich is good when you can build a big box and use triode amplifiers, but bad when they will be put in a small box powered by transistors...

I've thought long and hard about the 165LB though.. But it gets a little big for decent bass response..

 

[SunRa]

You are right Rocky... I guess that afterall these drivers will do their best in a TQWT (and I think they will be quite slim)...
Nevertheless I think that it's quite hard to use a fullrange in a bookshelf... they just don't fit...

Have you seen this?
http://www.diyaudio.com/forums/showthread.php?s=&threadid=80846

It's a good design I guess... quite expensive though...I don't exactly know the price of the drivers

 

[renfrow]

You might try the Fostex FE127E in a bass reflex box. Here's the url for it: FE127E Bass Reflex

An externally hosted image should be here but it was not working when we last tested it.

This is from the 'diyAudio Full Range Reference Project' thread.

Tom.

 

[Rocky]

Supravox TLs would be way cool, I agree. A shame I can't try it as I don't have the funds to build on more than my main setup (student budget). I do however have one supravox-driver in my mind for a future project, and that is the big badass field coil bass. That one would be tha bomb below my 350Hz tractrix horns

That Fostex in the last post look nice. Very nice, but only for certain types of music... Most likely I could live with such a speaker for a while as I'm a calm guy playing mostly classical and chill stuff. My sister on the other hand, can at times be quite a noisy woman.. I suspect the FE127 would probably mud up some of her stuff like the Aphex Twin CDs... (I have actually had the FE127 in percisely a BR, so I know it to be a fact..)


Looking into some other stuff.........

I've broken the CSS FR125S down to a Mathematica worksheet, and I am tempted to try that driver.. Granted, it has low efficiency but as said that's OK in this project.. Xmax is incredible however, and bass output is excellent. Price is nice.. Think I'll build a thorough simulation on this driver and talk to Dave.. If anyone has those impedance curves, could you check if my attached curve is far off? It is based on the T/S numbers and that isn't always spot-on..

 

[ruerose]

http://www.zaphaudio.com/4.5test/

Curves listed there.

Tests the WR125, should be similar for the FR125.

I own a set of FR125's and they sound spectacular, but they do not go terribly loud before starting to break up.

10-11L Is a little to big IMO, you can shrink this down to 7 even with very good results.

I much prefer the "full range" of the FR125s over a lot of the other popular but smaller full ranger's. But don't forget Baffle Step Compensation, some like it bright, but mabye not that bright.

Watch your excurtion curves also, probably won't overpower them off a JVC mini.


BSC Calc:
http://www.tolvan.com/edge/help.htm

Win ISD
http://www.linearteam.dk/

You will need to manually enter in the driver.
(normal beta version lets you do box volume, but has no excursion or delay curves)
(Pro alpha version has lots more curves [excursion, delay, wind velocity, etc] but has no box volume calculator)

 

[navin]

what about the reference project on the fullrange forum

http://www.diyaudio.com/forums/showthread.php?s=&threadid=46934

 

[Rocky]

I'm jumping a little back and forth on driver choice, obviously I haven't quite made up my mind yet I read the first 20 pages or so of the reference thread.. I did get an idea from it; making a small TL instead of BR... I attached a drawing along the lines of what I'm thinking, using the FX120 driver.. How would something like that compare to a bass reflex box? I don't have any experience with transmission lines, it's why I'm asking..

 

[Rocky]

Just thinking out loud here.. here is a sphere with the fr125s driver.. BR design with port at the rear, and driver is tilted about 4 degrees downwards, as the shelf where they'll sit is above listening position. The sphere will hopefully avoid the BSC issue, but it may be tricky to construct. Luckily, we have a part printer at school that can print the shell if I keep diameter below 25~30cm. I could then dress the shell (made from a sort of epoxy impregnated powder composite) in fiberglass or something, or make a mold...

 

[burgunder]

what about the reference project on the fullrange forum

http://www.diyaudio.com/forums/showthread.php?s=&threadid=46934

I was thinking that the tombstone reference design might be suited for some kind of bookshelf/wall placement. Has anybody ever build this design and how was the sound? Could they be used as wallspeakers?

 

[paba]

Hi,
I'm very pleased with the Fostex recommended BR cabinet shown on page 2 of the link below. I use them every day for background music on my second system. I added some felt to the inside walls.
One negative is the lowish power handling but for my setup it is fine. Oh and when I put them directly on the floor the bass output is surprising for a 5 liter cabinet and a tiny full ranger.
Very nice at mid range and highs.


http://www.solen.ca/pics/fostex/ff85k_enc.pdf

 

[Rocky]

I really love the appereance of the sphere that's evolving in my CAD.. I will go with that design. It will undoubtly be a bass reflex, and not using a high efficiency driver as I need some low end in moderate volume. Also, it will need a round frame to fit nicely in the sphere, and I will not use a Tang Band for this project.. That leaves me with two drivers of interest; the jordan and the CSS. The CSS fits my budget better than the Jordans and I think it will perform well for the design, so FR125S it is. My mind is set.

I am posting another thread in the loudspeakers forum to see if anyone has construction tips for the spheres, such as materials, etchniques, etc..

If I get the box right, I think these will make my sister very happy

 

[lndm]

Cool design. I think you'll still need to do BSC, long wavelengths will still reach around this enclosure.

The equidistance from driver centre to cabinet edges xeye: ) may (if I've haven't got it wrong ) increase the rolloff at the knee, but the smooth transition of the curved edges might also stretch the rolloff out again.

 

[Rocky]

The equidistance from driver centre to cabinet edges xeye: )

OK.. I know the "equidistance" term very well from my days running orienteering (U know the strange activity where one runs around in the woods with map and compass) but I think it was the "cabinet edges" part of your sentence which had me confused

EDIT: Ah, I'm just a little slow tonight. I got what you were saying now I think.

 

[ruerose]

Make the speaker terminal plate not permanent and see how it sounds without BSC first. It might suit the application. If you still need it, you can add it on the back of the plate, or still stuff a board inside.

I don't have BSC on my towers, and they are a tad beamy, but still quite listenable. A sphere enclosure will have even less boost to worry about.