Hi folks,
I've caught the diy bug and looking at putting together my first pair of full range speakers. I've looked at the fonkens, the zigmahornets and the Brines' FB-16s. I'm thinking that for my purposes the fe167e drivers will fit the bill. In terms of size I'm looking at a bookshelf and at the same time, I think the fe167e would offer some more bottom end. I've looked at the Fostex recommended designs for the fe167e and I like the idea of the "standard recommended bass reflex type " enclosure located at the bottom of the page:
http://www.solen.ca/pics/fostex/fe167e_enc.pdf
My concern is that it's a 15 litre box and may not give me the lower end punch that a bigger box may be able to. I then looked at Godzilla's measurement table and found a 25 litre box that's based on the simple fostex design but just expanded to 25 litres.
http://www.zillaspeak.com/FostexReflexCabsFE.asp
Can you share your thoughts as to this design and what I can expect. Has anyone used the design measurements on godzilla's site and if so, what did you think of it.
Thanks
I've caught the diy bug and looking at putting together my first pair of full range speakers. I've looked at the fonkens, the zigmahornets and the Brines' FB-16s. I'm thinking that for my purposes the fe167e drivers will fit the bill. In terms of size I'm looking at a bookshelf and at the same time, I think the fe167e would offer some more bottom end. I've looked at the Fostex recommended designs for the fe167e and I like the idea of the "standard recommended bass reflex type " enclosure located at the bottom of the page:
http://www.solen.ca/pics/fostex/fe167e_enc.pdf
My concern is that it's a 15 litre box and may not give me the lower end punch that a bigger box may be able to. I then looked at Godzilla's measurement table and found a 25 litre box that's based on the simple fostex design but just expanded to 25 litres.
http://www.zillaspeak.com/FostexReflexCabsFE.asp
Can you share your thoughts as to this design and what I can expect. Has anyone used the design measurements on godzilla's site and if so, what did you think of it.
Thanks
Go to these websites for details:
http://geocities.com/rbrines1/
at this site you buy the speaker plan, a floor standing one
http://www.quarter-wave.com/
at this site you get it for free.
cheers.
http://geocities.com/rbrines1/
at this site you buy the speaker plan, a floor standing one
http://www.quarter-wave.com/
at this site you get it for free.
cheers.
We did up a 15 litre for the FE167 when we were figuring our 1st round of driver mods... we tned it a bit lower then the factory box (increased port length to 2.5"). The 167 is capable of fairly prodigous bass in a big enuff box (ML-TL, ML-V (like Demetri), Metroniome)
It wasn't a Fonken but had more bass (not many of the other Fostex drivers can do midrange like a modded FE127 in a Fonken
dave
It wasn't a Fonken but had more bass (not many of the other Fostex drivers can do midrange like a modded FE127 in a Fonken
dave
My 167s in MLTLs are good for 40Hz, usable to the low 30s. Imaging's as good as it gets for driver larger than 4 1/2in, though something like the Fonkens would paste it in this respect (I can feel a comparison between the Fonkens, my 167s, Steve's Metronomes, Nicks OBs and Ed's Vofos coming on... 🙂 )
I posted something more detailed over on the WD forum, but I might as well add it here too.
Firstly, you need to be a bit careful here. The dimensions on Zillaspeak are actually for the discontinued FE167, not the current FE167E, which has different parameters. Jeff's copied them over from the Fostex site, for discontinued driver models.
If you want a good standmount / bookshelf for the 167, then I'd build something on these lines, if you didn't want to buy a set of plans from Bob (which IMO would be worth doing -Bob's a master at refining boxes). It has a similar volume to the Fostex box you mention, and a little more than the FB-16 apparantly has,but the alignment will probably be similar to Bob's (I don't know what the FB-16 internals are like, but I suspect we've got a similar take, though I usually prefer a narrower front baffle unless a full-blown WB box is wanted).
Internal dimensions 19in x 6.75in x 12in (HxWxD). Driver-centre 9.5in down from the internal top (i.e. at the half-way point). Port centre is 3in up from the internal bottom. Port is 2in in diameter and 2in long. Line the cabinet with carpet underlay or similar, top, bottom, rear and one side-wall, or stuff it 0.2lbs ft^3 of material in the upper 10in.
As you can see from the attached FR graph, this gives an EBS alignment, which should give decent extension without boom (which you'd get from a reflex box if you used a QB3 max-flat alignment. Impedance is steeper than an MLTL floorstander, but nothing to get worked up about. Driver excursion is fairly mild too. Should make a nice little standmount.
Firstly, you need to be a bit careful here. The dimensions on Zillaspeak are actually for the discontinued FE167, not the current FE167E, which has different parameters. Jeff's copied them over from the Fostex site, for discontinued driver models.
If you want a good standmount / bookshelf for the 167, then I'd build something on these lines, if you didn't want to buy a set of plans from Bob (which IMO would be worth doing -Bob's a master at refining boxes). It has a similar volume to the Fostex box you mention, and a little more than the FB-16 apparantly has,but the alignment will probably be similar to Bob's (I don't know what the FB-16 internals are like, but I suspect we've got a similar take, though I usually prefer a narrower front baffle unless a full-blown WB box is wanted).
Internal dimensions 19in x 6.75in x 12in (HxWxD). Driver-centre 9.5in down from the internal top (i.e. at the half-way point). Port centre is 3in up from the internal bottom. Port is 2in in diameter and 2in long. Line the cabinet with carpet underlay or similar, top, bottom, rear and one side-wall, or stuff it 0.2lbs ft^3 of material in the upper 10in.
As you can see from the attached FR graph, this gives an EBS alignment, which should give decent extension without boom (which you'd get from a reflex box if you used a QB3 max-flat alignment. Impedance is steeper than an MLTL floorstander, but nothing to get worked up about. Driver excursion is fairly mild too. Should make a nice little standmount.
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Scottmoose said:
Good work Scottmoose..
Maybe baffle step compensation should be taken into account....otherwise speakers will exhibit any bass.
I'd assumed these would be used on a shelf or similar (I can't see the point of stands when using a moderate sized driver or larger -you might as well just build a floorstander for them & have done with it). Hence I didn't bother giving any BSC values.
If desired, I'd use a 4ohm resistor paralleled with a 1.2mH inductor. The 167 doesn't benefit as much from a zobel as some of the other units, but again if desired, an 8ohm resistor with a 5uF cap would do the trick.
If desired, I'd use a 4ohm resistor paralleled with a 1.2mH inductor. The 167 doesn't benefit as much from a zobel as some of the other units, but again if desired, an 8ohm resistor with a 5uF cap would do the trick.
Thanks Scott,
You helped me avoid a whole bunch of frustration. I assumed that the reference in godzilla's table to fe167 was simply a typo that missed the "e" after the 167. Thanks for the dimensions, they're exactly what I was looking for. One last question. It seems that my needs may either be met by the enclosure you described or by going for the fonkens. Can you explain what the major differences would be between the two.
Thanks
You helped me avoid a whole bunch of frustration. I assumed that the reference in godzilla's table to fe167 was simply a typo that missed the "e" after the 167. Thanks for the dimensions, they're exactly what I was looking for. One last question. It seems that my needs may either be met by the enclosure you described or by going for the fonkens. Can you explain what the major differences would be between the two.
Thanks
The 167s will go lower, louder & have very good imaging by most standards. The Fonkens counter with imaging that borders on the supernatural. I gather electrostatics start shaking whenever their name is mentioned. 🙂
If I wanted a pair of standmounts / bookshelves, I'd go for the Fonkens. Keep the larger drivers for floorstanders. Depends on what you listen to.
If I wanted a pair of standmounts / bookshelves, I'd go for the Fonkens. Keep the larger drivers for floorstanders. Depends on what you listen to.
Not my phrase Ed. I suspect there's a little exaggeration there, but the reports I hear suggest it's not actually as much as we'd think.
A comparison might be possible at some point over the next few months. 🙂
A comparison might be possible at some point over the next few months. 🙂
Scottmoose said:
The mFonken isn't quite as boxless as the full-blown Fonken...
My Fonkens image better than my Acoustat 2s ever did
dave
Scottmoose said:
Relatively the Fonken is a big speaker compared to the mFonken (13l vrs 4.5l)
And a µFonken is in the works.
🙂
dave
Scott,
At the risk of abusing your generosity would you be kind enough to give me similar measurements for a 20 litre box. I'm thinking that a standmount may fit in better for me.
I'm curious Scott, do you use a software program to put together these numbers? Either way, its quite impressive.
Thanks
At the risk of abusing your generosity would you be kind enough to give me similar measurements for a 20 litre box. I'm thinking that a standmount may fit in better for me.
I'm curious Scott, do you use a software program to put together these numbers? Either way, its quite impressive.
Thanks
That was a standmount. 😉
Reducing volume to 20 litres (hold all dimensions as per above, just reduce internal depth to 9.5in) without any other changes gives a ~max-flat alignment. If you went for this shallower, reduced volume box, then I'd increase vent length to 2.5in. On the whole, I'd go for the larger box if possible; the difference in dimensions isn't great.
Software? Martin King's MathCad worksheets. They don't / can't design cabinets for you (you have to know how to do that yourself) but they're IMHO the finest modelling software publically available for simulating enclosures, and allow details to be adjusted / refined and their effects examined.
Reducing volume to 20 litres (hold all dimensions as per above, just reduce internal depth to 9.5in) without any other changes gives a ~max-flat alignment. If you went for this shallower, reduced volume box, then I'd increase vent length to 2.5in. On the whole, I'd go for the larger box if possible; the difference in dimensions isn't great.
Software? Martin King's MathCad worksheets. They don't / can't design cabinets for you (you have to know how to do that yourself) but they're IMHO the finest modelling software publically available for simulating enclosures, and allow details to be adjusted / refined and their effects examined.
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