I’m trying to design a 3-way speaker box with several limiting factors in place that must be adhered to.
I’ll be cutting all the pieces on my CNC machine, no exceptions. My CNC is a small one so no piece can exceed 10” in length or width.
I already own drivers and they are:
Peerless (Tymphany) XT25SC90-04 1" tweeter
Scan-Speak Discovery 10F 4” midrange
5.25” Boston Acoustics woofer (from a 2-way component car speaker kit bought in 1999)
Also, this system will have a Polk Audio PSW10 10" Powered Subwoofer for the low end.
Can these components deliver good sound from a fairly simple box design? Do I need to swap one of the drivers for something else? I’d like to use all these drivers but if one or more of them is going to make the speaker sound bad then I’ll swap.
I’ll be cutting all the pieces on my CNC machine, no exceptions. My CNC is a small one so no piece can exceed 10” in length or width.
I already own drivers and they are:
Peerless (Tymphany) XT25SC90-04 1" tweeter
Scan-Speak Discovery 10F 4” midrange
5.25” Boston Acoustics woofer (from a 2-way component car speaker kit bought in 1999)
Also, this system will have a Polk Audio PSW10 10" Powered Subwoofer for the low end.
Can these components deliver good sound from a fairly simple box design? Do I need to swap one of the drivers for something else? I’d like to use all these drivers but if one or more of them is going to make the speaker sound bad then I’ll swap.
If you want it simple it is going to be a box with four sides, top and bottom. 10" max dimension. Cut sheet of paper 10" x 10", lay the drivers on it and see how you are going to fit them. Tweeter and 10F as close together as possible, on same vertical line. Put the woofer where it fits, avoid putting it next to the tweeter for a bit less diffraction. Round corners of the front panel and call it a day. If you want it simpler, leave the tweeter out. Even simpler, leave the woofer out and use the 10f only.
Crossovers will be used, maybe passive, maybe active via one of the Dayton Audio boards that have DSP built in.
As for the enclosure, I know space is tight and the 5.25" will want some room to breathe, and the 4" mid also. I'd thought about making the enclosure a 2-part deal, with maybe 1 box just for the woofer and a separate but adjoined box for the mid and tweet.
As for the enclosure, I know space is tight and the 5.25" will want some room to breathe, and the 4" mid also. I'd thought about making the enclosure a 2-part deal, with maybe 1 box just for the woofer and a separate but adjoined box for the mid and tweet.
Actually, only the woofer needs a box; ideally, the woofer needs the backwave to be eliminated, so no "breathe" or whatsoever. But you can't do that, only attenuate it, or separate your listening room from what the woofer emits from the back.
The back wave from the midrange can be easily damped by the means of a cell made of felt.
The tweeter...
The setting in the listening room will tell you how to accomodate (vertically) the three drivers ( which are six...).
The woofer needs to be equi-distant from floor and from ceiling...
DSP and digital for me are nasty so I won't pronounce on that 🙄
The back wave from the midrange can be easily damped by the means of a cell made of felt.
The tweeter...
The setting in the listening room will tell you how to accomodate (vertically) the three drivers ( which are six...).
The woofer needs to be equi-distant from floor and from ceiling...
DSP and digital for me are nasty so I won't pronounce on that 🙄
I guess all the drivers are 4 Ω and that you have a ready made crossover ( car component) for the purpose...
I'm thinking that I might use a Pioneer DEH-80PRS that I took out of my truck (hardly used). It has a nice little 3-way active x-over, 5Volt RCA outs, and a remote control for Volume. I'll use a Polk Audio D4000.4 car amp to drive the woofs and mids, might try the onboard amp of the Pioneer to drive the tweets. (Or may scrap the Pioneer/Polk Audio gear idea completely once I see how much it's gonna cost me to supply them with 12V @ enough current!)
Hmmmmm....so I can just build a box for the woofer and maybe a second fairly shallow box for the mid and tweet and attach it atop the woofer box?
I have the 10F, the 5.25in Polk woofer from HD5 bookshelf and the PSW10 sub. Skip the tweeter.
Make a small sealed bookshelf FAST 2 way sort of like this, but use 10F instead of FR58EX. Good for 100Hz to 16kHz. Use the PSW10 below 100Hz. Should sound great.
FR58EX and AC130F1 micro-FAST / WAW
If you must use the tweeter, do a crossover at 5.5k and let the 10F do its magic from 1kHz to 5k5. That is where the rich smooth midrange and imaging all resides.
Make a small sealed bookshelf FAST 2 way sort of like this, but use 10F instead of FR58EX. Good for 100Hz to 16kHz. Use the PSW10 below 100Hz. Should sound great.
FR58EX and AC130F1 micro-FAST / WAW
If you must use the tweeter, do a crossover at 5.5k and let the 10F do its magic from 1kHz to 5k5. That is where the rich smooth midrange and imaging all resides.
Good info, thanks everybody! xrk971, I'm going to go with your recommendation I think. I'll try both with and without the tweeter.
I'm no audiophile but I've been listening since 1983 and still have as my daily drivers a pair of Cerwin Vega D3's I bought back in 1985. My tastes have changed so more likely those CV's are playing Miles Davis nowadays instead of the Rolling Stones as back in the day.
Funny thing, I currently listen to, please try not to laugh, a 5.25" 2-way Advent wireless speaker that I converted to wired, with integrated Dayton Audio 15W amp, with, get this, both L and R channels merged. And you know what? It doesn't sound half bad in a 12' x 20' room! Thought about bringing the D3's into the house but they're so big and I don't listen at loud volumes much anymore, so I decided to leave them in my workshop.
Sorry for the ramble, I don't socialize much.
I'm no audiophile but I've been listening since 1983 and still have as my daily drivers a pair of Cerwin Vega D3's I bought back in 1985. My tastes have changed so more likely those CV's are playing Miles Davis nowadays instead of the Rolling Stones as back in the day.
Funny thing, I currently listen to, please try not to laugh, a 5.25" 2-way Advent wireless speaker that I converted to wired, with integrated Dayton Audio 15W amp, with, get this, both L and R channels merged. And you know what? It doesn't sound half bad in a 12' x 20' room! Thought about bringing the D3's into the house but they're so big and I don't listen at loud volumes much anymore, so I decided to leave them in my workshop.
Sorry for the ramble, I don't socialize much.
Hi Bigma,
Good luck on your build! Are you reusing a box or making a new one? If you want to make something cheap and quick to test out but don’t want to cut wood try something like this - it can actually sound great. No need to use wood if you have proper butyl damping and natural absorption of foam core.
RST28F and DC130A Foamcore Homage to LS3/5A
I bet the hole for the dome tweeter is the same as the cutout for the 10F.
Good luck on your build! Are you reusing a box or making a new one? If you want to make something cheap and quick to test out but don’t want to cut wood try something like this - it can actually sound great. No need to use wood if you have proper butyl damping and natural absorption of foam core.
RST28F and DC130A Foamcore Homage to LS3/5A
I bet the hole for the dome tweeter is the same as the cutout for the 10F.
I'll use wood because I already have plenty of top grade Baltic Birch plywood 12mm and a CNC to cut it, I'll design it in Fusion 360. I had no idea you could just use foam core! Aren't they more likely to vibrate?
Yes, but with foam core bracing and butyl liner it sounds and measures just as good as BB ply cabinet. You can also add thin layer of 3/16in luan plywood cover with latex caulking for a CLD panel.
To give you an idea of a passive crossover that I used for my 10F/RS225 FAST speaker, it costs about $110 for two. Most of the cost was in the air core 4mH inductor and the large 61uF cap (2x 27uF + 6.8uF). You could use a laminated iron core inductor (1/4th price) and perhaps use a 50uF bipolar electrolytic with a 10uF film cap. You can cut the price substantially.
Whereas the crossover for my homage to the LS5/3A with iron core 5mH inductor was closer to $60 for the pair:
Whereas the crossover for my homage to the LS5/3A with iron core 5mH inductor was closer to $60 for the pair:
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10F needs 1L to 2L sealed rear chamber. The main chamber is for the woofer so design that for the optimal volume for the bass you need. For 10F make a 5 sided tall pyramid if you have a CNC. Or use a sports cone 9in to 11in tall works well.