css fr125s

[joe perry]

would it be possible to build a good sounding floorstander
with 4 fr125s per speaker in a ported or sealed or
transmission line enclosure

would this speaker be phase and time coherent if all
the drivers were firing forward ??????

basically i am looking for a fairly high output floorstander
with decent bass response to around 40hz so my
thoughts are that the more drivers the better when
it comes to bass and power handling

thanks for any help or reply

[ruerose]

you're better pairing the fr125s with an extremis 6.8 in a 2-way design like the the RAW series drivers.

Because the FR is a full range driver, there will be comb filtering.

[edjosh23]

joe perry,

With 4 full range drivers you will run into lobing issues.
If you want to run that route you could use 4 wr125s and a single tweeter. You can look at Cal's wr125st MTM and perhaps do something similar but adding 2 more woofers (all of your woofers would be wr125s, not wr125st).

Josh

[chrisb]

Think something like the HT3, less the ribbon. To keep things simple, a single FR125 and Extremis per side will be much more coherent than multiples of the smaller driver, and kick some serious a-s-s as far as bass extension is concerned.

You can get as elaborate as you like with the XO. Note that RAW's crossovers tend to be high order & parts count (more than some smalll SET amps ) - you could probably get by with something much simpler to start - 1st order at around 120-150 maybe?

[TerryO]

Originally posted by chrisb
Think something like the HT3, less the ribbon. To keep things simple, a single FR125 and Extremis per side will be much more coherent than multiples of the smaller driver, and kick some serious a-s-s as far as bass extension is concerned.

You can get as elaborate as you like with the XO. Note that RAW's crossovers tend to be high order & parts count (more than some smalll SET amps ) - you could probably get by with something much simpler to start - 1st order at around 120-150 maybe?

I've thought about using much the same combination as Chris mentions, especially in a quasi-Basszilla configuration. If you do go 1st order, I'd suggest that you give the FR's some slack and a chance to obtain a lot more headroom by crossing over at least 2 octaves over the FR 125's FS. The higher in frequency you go, the cheaper the componets of your crossover become, but I think that 275 to 350 Hz would be as high as you'd want to try in order to stay out of the usual vocal range. Also, my general impression is that if you do go for a low order crossover that you'd want those drivers physically a lot closer together in order to better integrate the drivers. The HT-3 uses a high order crossover to prevent a loss of focus at the crossover frequency due to the physical distance and orientation between the drivers. One option you may want to entertain is the use of a higher order on the Extremis, tailored to integrate with the 125's 1st order crossover.

Please note that I'm not a crossover Guru and therefore any or all of my advice should be taken with a healthy (or not so healthy!) helping of Salt


Hope some of this may help.
Best Regards,
TerryO

[Cal Weldon]

Hi Joe,

I like the others ideas of an Extremis with an FR.

My MTM which is actually a 2.5 way, is a bit of a conundrum to me. I really like the sound they produced but they can't be pushed, not at all.

Consequently, they have been banished to a shelf for bad behaviour.

I think the Extremis is needed for the low end and if you are cutting the FR off at 100 to 200 then I would use a second order. I tried a first order at about 100 and it hardly made a difference. The little WR's still flopped around like crazy. I really think they need to be cut off steeper.

You might even want to consider an FR on the front, a WR and small tweeter on the back, and a side mounted Extremis.

Or go crazy like me and start throwing plate amps and stuff at it and see how many drivers and other gear you can fit into one cabinet and still have it sound good.


Message to self: Stop promoting your self-serving style of building, someone might actually follow your lead.