3 liters - coax or fullrange

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Hi!

I'm thinking about building speakers for my PC desk, that will be sitting on the desk or in a bookshelf. I was thinking about getting some 4-5 inch coaxes, that will manage to work in a 3l vented cabinet. We're talking budget options here, since these speakers will play mostly spotify over bluetooth and windows chimes. These speakers will be used to listen to quiet jazz and classical music from a D-class amp.

I was thinking of getting a pair of SB12PFC25-4-COAX from SB Acoustics. They have even published an XO design and box recommendations:

http://www.madisoundspeakerstore.com/pdf/sbacoustics_4in_SB12PFC25-4-COAX-pre.pdf
https://www.madisoundspeakerstore.com/pdf/SBAcoustic_PFC_Coaxial_Crossover_Designs.pdf

A pair of this with XO components will set me back about 200 euros. Are there better coax options for 3L boxes? Or in terms of IQ I should look at full range options, since 100 euro per speaker will be a possibility? Which would you guys recommend?
 
So what's wrong with the 4inch SBA coax? They claim, that it will do F3 at around 70Hz in a 2,8 liter box with 1" diameter vent by 4" long BR port. I've looked at WinISD, and it actually simulates that way.

If not a 3L BR with a 4 inch FR, maybe a passive radiator would help a bit? A good FullRange + passive radiator?
 
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It is quite acceptable. I have mine in. BR tunes to 75hz.

I can fill in with SW but for stereo music often I don't. I may have quite a bit of LF room gain. I am not a measurer, just a listener.

I believe the ferrite 3fe25 can go lower but need more volume.

I think near field they will be good. I use in a room 4mx5m and powered by tpa3255.
 
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I've just built some little 3 liter boxes using BMS 5C150 for surrounds but was so impressed with them I have been using them as my main L&R for weeks (with subs) and built more for center and surrounds!
Faital 3FE22 or 4FE32 are very nice for a simple solution without the hassle/cost of designing a crossover though!
 
It looks like 4FE32 provides very similar bass response to the SBA 4" coax in a similar enclosure. Costs roughly the same and you do need to pay for XO components.

Would it sound better for quiet listening? Better i.e. distortions, tonal balance, etc? I see people complain about needing to take the 7kHZ are down, so I'd need to buy some XO components after all.
 
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I think you will run in to distortion quite quickly with the 3FE25. Xmax is tiny at 1.73 mm and although you are using them up close anything below 200hz risks this distortion.

Alpair 5 Gen 2 is a good shout and there is an extended bass design by Scott kicking about somewhere... https://stat.ameba.jp/user_images/20170622/05/room335xxx/a2/1c/j/o0775064213966091695.jpg?caw=800

A 5 litre box but hey...

The Dayton ND91 requires a very small box, perhaps investigate that? I have heard it isn't as bright as other full rangers but could be tinkered with in the crossover.
 
I've had some time with the internet and winISD. I've checked which ones can I get in PL. I've found DaytonAudio RS100-4 4" full range. It can go in a 3L enclosure. Xmax is not so small as in Fostex-es, people do not complain on harshness of highs and mids so much. Would this be an option worth considering?
 
ok, two things happened:
1. my friend does actually have fullranges based on RS100-4, so I'll be happy to get something different, just for the sake of being able to compare this afterwards
2. I've got my hands on klang+ton in German. These guys went over the SBA's coaxes and decided that the 4incher is a good alternative to fullranges. So not a disaster.

I'll guess I'll get the fullrange then and see what comes out of it.
 
So what's wrong with the 4inch SBA coax?

If not a 3L BR with a 4 inch FR, maybe a passive radiator would help a bit?

The pioneers concluded that the best overall alignment performance wise was one where Vas/1.44 tuned to Fs = ~3.33 L net/~58 Hz Fb, so any other alignment will have its +/- in one or more ways, but can still sim good/perform 'good enough', so recommend comparing based on this alignment to decide whether or not the trade-off are acceptable.

PRs tend to be somewhat noisy below tuning, so in general are only used for very low tunings; best then to use a hi-pass ['rumble'] filter when tuning high up in the bass.

GM
 
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