suggestions for FAST driver/enclosure

[IMGDEAD]http://i455.photobucket.com/albums/qq271/tilroh/phono/4amp6quotMLTLampsubs_zps9ducbu9o.jpg~original[/IMGDEAD]

I've built a pair of 55Lt vented boxes with Dayton Audio RS225-8 8" Reference Woofers driven by a 50w/c transistor amp.
I use them with the Fostex FF165WK MLTLs which are powered by a EL34 tube amp in winter and a SMSL TPA3118D2 in summer.
The active XO is 80hz. Equalization is taken care of by the FooBar MathAudio plugin.

I'd like to replace Fostex MLTLs with smaller boxes.

The idea of a FAST system is extremely appealing. Has anyone found a good match for the RS225-8s? What enclosure volume? Sealed? XO point?

I like paying for plans.

I'm in Australia so driver selection is limited.:mad:

Thanks, Mack
 
Here is my FAST with the RS225-8. The 10F/8424 is a superb driver to go with RS225 but even a TG9FD would work. Visaton B80 works well, PS95-8, P830986, SB65WBAC25-4, and even FF85Wk. All of them go with a Dagger back chamber that's inside the main woofer cabinet (tall 3 sided sealed (stuffed) pyramid about 1.5liters - no parallel walls zero back reflection. ) that should be enough choices for you. If you use Foobar you can implement Linkwitz transform and go sealed sub. XO at 350Hz.

http://www.diyaudio.com/forums/full-range/273524-10f-8424-rs225-8-fast-ref-monitor.html

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Hi there X: superb response graph for the Ref monitor rss288/10F...how does it sound compared to your Danley single point horn...which you refer too as your goto reference? ...Michael

Two very different speakers. The 10F/RS225 is a direct radiator and has all the pitfalls and advantages of such a speaker: reflections from walls and ceilings diffuse the sound but very easy direct sound when not pushed hard. They don't go very loud as the single 8in woofer runs out of Xmax when used with LT. Dual 8's in a tapered stuffed PMC style TL would be another story though. The 10F on top cannot be faulted. About as low of a distortion mid tweet that you can buy and the fiberglass cone has a glass like smoothness to mids and female vocals.

The point source multiway horn on the other hand limits spray from walls and ceilings and the direct to reflected sound ratio is very high. Like headphones as they say but without the image or soundstage stuck in between your ears. The horns get louder have less distortion and have an ease of dynamics that is amazing. However they are more complicated to make and to tune even with miniDSP.

The 10F/RS225 is easily flatter frequency response so technically - is more of a monitor. The sound is as intended by the recording engineer.
 
Those small boxes (Alpair 7's?) sitting on top of the woofer modules wouldn't work with a higher xover point?

jeff

I think the 7.3a MLTLs would work but they are too good as computer monitors. Up close they have quite an impact.
There is a Dayton SD215A-88 8 DVC under the desk taking care of 100Hz and below. MathAudio (for Mac) levels everything out.

[IMGDEAD]https://i455.photobucket.com/albums/qq271/tilroh/phono/My%20desk%20speakers%20-%201_zpsogeuzz19.jpg[/IMGDEAD]
 

Bob Brines

Member
2003-01-31 10:11 pm
I think the 7.3a MLTLs would work but they are too good as computer monitors. Up close they have quite an impact.
There is a Dayton SD215A-88 8 DVC under the desk taking care of 100Hz and below. MathAudio (for Mac) levels everything out.

[IMGDEAD]https://i455.photobucket.com/albums/qq271/tilroh/phono/My%20desk%20speakers%20-%201_zpsogeuzz19.jpg[/IMGDEAD]

One of my better efforts, no? And no, they are TL's, not MLTL's. But more to the point, I have uses those speakers successfully with the larger RSS315HF-4's. I see no reason why they would not work well with the 225's.

Bob
 

Bob Brines

Member
2003-01-31 10:11 pm
I've found a dealer near me that carries the Scan-Speak 10F/8424G00.


Just to double check....

XO is at 300Hz

That's about as low as you can safely go.

sealed box vol is 1.5Lts

Thanks! Mack

That will work. I used a 4"x10" PVC pipe and stuffed it with rock wool. Behaves pretty much like in free air. Doesn't matter if the pipe is open or closed.

Bob
 

Bob Brines

Member
2003-01-31 10:11 pm
Do what you need to do to get the results you want. However, I was admirably successful running a Hasch XO at a nominal 300Hz (actual 268Hz) to an Audax HM210C0. Easily played [email protected] Distortion was only a problem at the bottom end which is typical of resonant cabinets (the Audax).

Doing the modeling, excursion doesn't become a problem until ~200Hz. If you but the 10F in 1l or less, excursion will never be a problem.

Bob
 

Bob Brines

Member
2003-01-31 10:11 pm
BTW here are some graphs of what I took to LSAF in Dallas. It is a work in progress and the cabinet (the Audax) needs some work. But....

Bob
 

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Veleric

Member
2016-02-26 6:26 pm
And no, they are TL's, not MLTL's.

Bob,
Not being able to see the internals, it's impossible (for me) to know for sure, but it seems likely from the pic that the terminus opening is smaller than the pipe area. So when you say that it's a "TL and not an MLTL", do you really mean it is a "negative taper TL and not an MLTL"? I'm definitely not trying to be argumentative, I'm just trying to be sure I understand.

Also, I'm curious is you have any experience with the MA Pluvia vs. the A7.3? It's half the price, so I'm wondering what you lose, if anything.

Thanks,
Eric
 
---- I used a 4"x10" PVC pipe and stuffed it with rock wool. Behaves pretty much like in free air. Doesn't matter if the pipe is open or closed.

Bob

Having only built BIBs MLTLs and TLs this tiny enclosure seems very strange to me. I guess volume is only needed for lower frequencies.

I think I'll build some sorta pods for the 10F/8424G00s, how heavy do the pods need to be to avoid being vibrated by the drivers? Do they need to be securely mounted? Vague questions I know.

I've ordered the XO, and have found local sources for the drivers. I'm forging ahead in spite of "knowing" those weeny 3.5" drivers are just too small to sound rich and full:confused:.

Thanks! Mack