Need advice beefing up my Froys (wmtmw?)

[MarkB1]

I have been enjoying my Froys for the last couple of months now, but as expected the bass is somewhat lacking. My plan has always been to add a home theatre style subwoofer (single driver in a box hidden somewhere to keep the other half happy)
She likes the look of the Froys quite a bit and said she wouldn't mind if they were bigger (main reason I went with the Froys was she said they had to be small and unobtrusive!)
I was smart enough to finish them off to match some of our existing furnishings (that she chose) so now she considers them to be furniture, not just speakers

SO, now what? My plan is to make them into a W-M-T-M-W using the SEAS W26. I realise that this is an expensive way to go, but in my budget I originally planned to build a 5 way surround setup however I have decided I would rather spend the money on my stereo speakers. (HT doesn't interest me that much really)
I plan to run the W26 drivers in stereo of course, and will run them off a separate amp with active crossover.

So my questions are:
*What do you guys think of this idea in general?
*Crossover point? (I am quite new to DIY and have very limited knowlege but I assume the W26's can go relatively high and take some load off the W15's)
*Enclosure design? I want all sealed and I assume the enclosure section for the W15's can be relatively small, also helping rolloff freq. I would like to keep the overall size relatively small so might undersize the W26 enclosures and use a boost circut to maintain LFE
*Should the drivers be positioned with w26 more forward and tweeter more rearward? (for alignment of phase??? please excuse my ignorance)

TIA

[5th element]

The Froys are REALLY small speakers and would look like furnature and be rather unobstrusive if finished to match the decor. A WMTMW with the FX's would be bloody huge in comparison, and very expensive.

Now if you really like the froys and your wife is happy with them, but the only thing you miss is bass, then why not add a sub.

A lot of work has gone into the crossover on the froy to get it sounding how it does, adding a pair of bass units will require a complete redesign of this and will probably end up spoiling the sound you like. If on the other hand you have measuring equipment and CAD software you should be able to make a good go of this. But if you want to add the bass you miss and keep the froys sound then the simplest thing just to add a a sub.

[MarkB1]

Do you really think it would require a redesign of the crossover? I was planning on powering the W26's with a separate amp using an active crossover (possibly from LC AUDIO) I know the result would be an expensive pair of loudspeakers, but I bought the components for my Froys about two years ago and this upgrade would cost less than the amount I initially spent on the Froys.
From what I have read, the W26's should work OK in a sealed box around 50L each, with some equalisation (available with the LC Audio crossover) I have done some rough sketches and I think I can make something that will fit nicely in the space allocated by "The Boss".

I am reluctant to pursue the HT style non stereo hidden sub, as I don't think it will give me what I want. I like the idea of the W26's as I believe they will hapilly run up to 200-300hz, so I can run the W15's in a sealed box and leave them to do what they do best. Obviously if I want to run subs this high, they will have to be stereo.

So, forgetting cost, and considering the 50L each, do you think the result would be good? The main thing i am interested in is how the W15's and W26's will work together.

[David Gatti]

I agree with 5th element. A wmtmw will be huge and very heavy.
How about a single 26W on each side, acting as a stand for the mtm Froy? It will give you plenty enough bass for music and be a much more manageable.

[PB2]

It will not require a redesign of the crossover if you cross low say around 100 Hz. The problem with a higher crossover is that your in the baffle compensation step region, so the woofer should start tapering down from about 100 Hz then break at the actual crossover point. You could cross higher if you take this into consideration. I think WMTMW would be difficult from a construction standpoint since, assuming 2 woofer boxes per side how would you combine all the boxes? Perhaps you have some creative ideas in which case you might want to look into Dunlavy designs to get some additional ideas.

What your looking for reminds me very much of the old Swan design that was in Speaker Builder many years ago. MTM on top of a 90 liter enclosure with two 12" woofers vented at 25 Hz - approximate B6 alignment (boost in the bass). I think a pair of W26s is a good idea if you want a low distortion design but the Vas is fairly high indicating that you'll need a large box if vented. You'd also have to do some alignment jaming to get them to work in a smaller vented box. You'd probably want to use a Linkwitz transform if you go sealed. Are you set one way or the other on vented or sealed?

Another similar idea is the Wilson WATT Puppy - pair of 8" vented at 28 Hz. The Puppy is an add on to the full range WATT, and I believe uses overlap between the two to compensate for the baffle step. You could use a pair of W22 woofers vented at 28 Hz and might consider some boost for an approximate B6 if you want a small enclosure.

I don't like mono subs, and I don't like the sub to be too far away from the mains unless the crossover is very low say below 50 Hz for an ultimate system. I don't think it can be said that one 10" per side is enough, it depends on your requirements and I believe your suggestion for 2 is much better.

These woofer boxes are likely to be large so your going to have to be creative to make it look good. You might consider a more narrow and deep enclosure, height to bring the Froys to the correct listening level.

Another thought - a pair of the Adire Extremis 6.8s on each side would allow for a small narrow woofer: http://www.adireaudio.com/TextPages/...eFrameText.htm

[MarkB1]

Originally posted by PB2
It will not require a redesign of the crossover if you cross low say around 100 Hz. The problem with a higher crossover is that your in the baffle compensation step region, so the woofer should start tapering down from about 100 Hz then break at the actual crossover point. You could cross higher if you take this into consideration. I think WMTMW would be difficult from a construction standpoint since, assuming 2 woofer boxes per side how would you combine all the boxes? Perhaps you have some creative ideas in which case you might want to look into Dunlavy designs to get some additional ideas.

What your looking for reminds me very much of the old Swan design that was in Speaker Builder many years ago. MTM on top of a 90 liter enclosure with two 12" woofers vented at 25 Hz - approximate B6 alignment (boost in the bass). I think a pair of W26s is a good idea if you want a low distortion design but the Vas is fairly high indicating that you'll need a large box if vented. You'd also have to do some alignment jaming to get them to work in a smaller vented box. You'd probably want to use a Linkwitz transform if you go sealed. Are you set one way or the other on vented or sealed?

Another similar idea is the Wilson WATT Puppy - pair of 8" vented at 28 Hz. The Puppy is an add on to the full range WATT, and I believe uses overlap between the two to compensate for the baffle step. You could use a pair of W22 woofers vented at 28 Hz and might consider some boost for an approximate B6 if you want a small enclosure.

I don't like mono subs, and I don't like the sub to be too far away from the mains unless the crossover is very low say below 50 Hz for an ultimate system. I don't think it can be said that one 10" per side is enough, it depends on your requirements and I believe your suggestion for 2 is much better.

These woofer boxes are likely to be large so your going to have to be creative to make it look good. You might consider a more narrow and deep enclosure, height to bring the Froys to the correct listening level.

Another thought - a pair of the Adire Extremis 6.8s on each side would allow for a small narrow woofer: http://www.adireaudio.com/TextPages/...eFrameText.htm

I am basically set on the idea of a sealed enclosure with the linkwitz transform. I have never been very happy with the sound of ported enclosures, though this may be due to the fact that I have never heard anything really good. This may sound strange but I actually (temporarily) blocked the ports on the froys and upped the bass adjustment on my amp and it sounds better to me. One of my speakers is surrounded on three sides with only about 1' clearance all around and I think this may adversely effect sound due to the rearward firing port on the Froys.
Regarding the enclosures, they can be as deep as our TV unit if necessary, wich is close to 2'. This should allow me to build an enclosure that is as narrow as the drivers will allow, and still not be too tall.
I will try to sketch something today and you can tell me what you think.
Thanks for your help.

[PB2]

You might want to try this parametric drawing spreadsheet to whip up quick concepts it's very easy to use:
http://www.audiodiycentral.com/tools.shtml

I reread your original post and noticed this time that it sounds like your planning to do completely new cabinets even for the MTM section am I reading you correctly?

[MarkB1]

Originally posted by PB2
You might want to try this parametric drawing spreadsheet to whip up quick concepts it's very easy to use:
http://www.audiodiycentral.com/tools.shtml

I reread your original post and noticed this time that it sounds like your planning to do completely new cabinets even for the MTM section am I reading you correctly?

Yes, exactly. the result would be one enclosure, but with the "froy section" being sealed separately. I would also plan on shaping the enclosures so the MTM section was waisted so as not to have a large flat panel section, giving excessive reflection. Does this make sense?

[John W]

Hi Mark,
Could I suggest that you take a look a the Ugly Duckling which uses the same drivers as the Froy and was developed by IJData to demonstrate LSPcad. It uses the Peerless XLS drivers and passive radiators for bass. You can down load the file http://www.ijdata.com/ugly_duckling.pdf

Of course if you have your sights set on the Excel 10" this doesnt help, but the slim cabinets are likely to have a much higher SAF than the 12"+ baffels and much larger cabs you'd end up with the Seas divers

John

[paulspencer]

The idea of using 4 x 10" drivers and bi-amping sounds like a good track to take to me. You can cross quite high, say 200 or 300 Hz, which can do a lot to improve the midrange, as well as the linearity and dynamics of the system. I suspect those 10" drivers will be fairly limited in the bass, however, in sealed boxes. TL's will be just too big. I think the system will be bass limited unless you either go with a vented alignment that you can live with, or cross to subwoofers.

I'd be suspicious of what you have heard in vented boxes. Sounds like a little experimentation is in order. How about making a pair of sealed/vented boxes - prototypes. Quick and simple. Perhaps room integration is an issue. You could try experimenting with some damping. Also you could design vented boxes with a lower tuning, a little like an EBS but not with quite the volume. The result is potentially tighter bass and lower GD.

If you still insist on sealed boxes, then perhaps you could cross to a sub in the midbass. Find the F3 of the sealed boxes, say 50 or 60 Hz then add a 2nd order high pass. Then use a 4th order slope with the sub.

I'd be wary of using a eq to get lower bass out of woofers, they just don't have the extension to do it with authority. What you get is the same GD as a vented box but less output and higher distortion! You may in fact end up with the weaknesses of a vented box without the advantage or more output!