CSS FR125S Cabinet

[Scottmoose]

Nice plan.

 

[inrank]

is that for the open baffle or the 1.5 way ones?

for the OB's, what kind of -3dB figure would i be looking at with 1x Fr125s and 2x RS225-4?

 

[lovechild]

Hi,

IMO all your plans are nice, but the OB one in particular.

But, for OBs you will aslo need some real space behind, AFAIK 3 - 5 feet for optimum performance, and it's not so easy to get some real bass from an OB - but I'm not an expert in OB at all - just reporting what I read...

What is wrong with the 1.5 way Jim suggested or the 45 degrees bipol from chrisb and dave?

best, LC

 

[inrank]

i dunno, lol

i just wanna make somthing different. (thats relativley easy to make)

in terms of aethetics, i prefere 'wide and thin' rather than 'thin and deep', so what would the best configuration be for this driver....

(i dont need that much bass as i allready have a subwoofer)

 

[planet10]

Re topfiring 2nd driver. I both instances of this config i've listened to (the EPI 250 & Linn isobarik) the speaker used the wall as part of the design.

The isobariks -- even as colored as they are) are a killer speaker.

dave

 

[inrank]

i am really liking the OB design, is 2ft from wall really too close?

 

[lovechild]

The isobariks -- even as colored as they are) are a killer speaker.

pretty cool looking too...

An externally hosted image should be here but it was not working when we last tested it.

Now the question is, will the FRs also have killer sound in this setup - as walways, only one way to find out ... what you think inrank.

btw. would they need a crossover or will both run fullrange???

LC

 

[Scottmoose]

2 foot too little? Nope, just make sure there's some heavy damping behind them, same as with the bipole. Actually, I've found dipoles are more forgiving about space behind them tha bipolars are. Odd, but there you go.

Oh, full range would be fine. Nothing particularly revolutionary about that -it's just like the Isobariks did, with full-range units. Guys -I loved the Isobarik too. I had a chance to buy a pair 18 months or so back, and I've been kicking myself ever since that I didn't. Most accurate bass I've ever heard. Ate amps for breakfast though, and rotten imaging. GM and I were talking about them via email a few days back. Output transistors tremble at the very mention of their name to this day over here in the UK. Flat Earthers still weep tears of joy. Best not mention the 6 pack Aktiv version with 6 Naim Audio NAP135 monoblock power amps though or you'll have them in hysterics.

Nice picture BTW

 

[inrank]

ok, so i have two options.

either...

1xFR125S and two woofers (mabye the Dayton RS225S-4) in Open Baffle

Or

1xFR125S facing forward and a WR/FR125S facing up in a 25 sealed cabinet.

cant decide...

here is a scale (rough) of the OB...

An externally hosted image should be here but it was not working when we last tested it.

 

[inrank]

OB apeals to me a lot aswell because i could make the side stands removable so it could be flatpacked as i go between home and uni.

although i would need a crossover, would a 2 way with two 4 ohm RS225's be best? and what would be the best crossover freq?

and is it a problem that the FR125S's are 86dB efficient and the RS225's 92dB efficient?

 

[planet10]

\although i would need a crossover, would a 2 way with two 4 ohm RS225's be best? and what would be the best crossover freq?\

You really should be bi-amping somewhere between 150 and 250 Hz....

You top woofer isn't going to do much except rattle the baffle. I'd put them both down near the floor, inside the wings.

dave

 

[planet10]

Something like this.

 

[inrank]

ok, so how can i bi amp it at 150-250Hz?

i was planning on making a gainclone, so does that mean i need to make two of them? and an active crossover?

thanks

is the sensitivity of the two drivers a problem?

 

[inrank]

also, what about this design?

An externally hosted image should be here but it was not working when we last tested it.

using 2 10" woofers rather than two 8"s, in a baffle 800mm x 300mm.
found these, http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=290-361 there cheap but would they be rubbish?
can i do better for max of £40 each?

thanks in advance

 

[westend]

Somewhere along the line I missed your intention for this build. If you want a good OB setup I would eliminate the FR125 altogether unless you plan to scavenge them from the previous project. I experimented with them in OB last fall and I think there are better choices to get some bass and volume. The 10" Goldwood from PE you linked to has potential but you mentioned you have a sub so I don't follow with that. If you're looking to experiment with OB and need a set to rock in your dorm room I'd hit up the thrift stores and/or Ebay for some likely canidates to keep cost low. If you can afford it the Visaton B200, Hemptone 8", or the Hawthorne 12" seem to be the darlings of the OB camp. Although I haven't heard them, the dipole with front firing FR125 and rear firing WR125 should be a sweet setup. More of the better stuff from both drivers and more bass, too. BTW, Planet 10's advice about placing the woofers lower substantiate what I found to give the most bass response in an OB alignment.

 

[inrank]

hi, sorry for the confusion.

all i want is the best use of this driver, i could buy other drivers but ive already got this one so i feel the need to use it and not wast it.

i like the idea of OB as it could be essentially flatpacked as i go between home and uni.

yes i do have a sub, but i want to try to use it as little as possible and just for movies.

and the other thing, as i am a design student, i want to have somthing different but also as simple as possible.

🙂

 

[planet10]

We tried FR125 in an OB, and it was limited to what it could do in the low bass -- that spawned an FR125/Extremis (or other suitable woofer(s) OB project similar to the one proposed here. With active XO the 125s would be just fine.

dave

 

[inrank]

yeah that sounds the kind of thing, but the extremis is a bit too much at the moment, have you any pics of this configuration?

 

[Scottmoose]

Re your last OB, that looks very much like the new Jamo type, and as Siegfried Linkwitz notes on his website, with the driver centres being so far apart, the polar response is going to be 'interesting'

 

[inrank]

Re your last OB, that looks very much like the new Jamo type, and as Siegfried Linkwitz notes on his website, with the driver centres being so far apart, the polar response is going to be 'interesting'

is that interesting good or bad? 😉

whats the driver centres?