hifiZen said:
The RonHorn Austin A166 offers much more. I can't recall the CC change recommended for the 166eSR -- Scott?
dave
It grew, but to what, I'm not sure. Have to ask Ron.
IIRC the factory ES-R cabinet is one of their better boxes (roughly based on the Nagaoka D-37). Not as refined as Ron's Austins of course, but not a bad design.
IIRC the factory ES-R cabinet is one of their better boxes (roughly based on the Nagaoka D-37). Not as refined as Ron's Austins of course, but not a bad design.
Scottmoose said:
Both the ESR cabinets have a much higher cut parts count and assembly time than the Austins. The 166 requires 42 cut parts per box , and the 206, 40
Since they follow the Nagaoka nested rectangular chamber format, it's (almost?) impossible to get all the necessary glue up and clamping complete in one session - and at over 4 full 4x8 sheets each for the 206, and 2 1/2 for 166, if you used MDF, they'd be nasty to move.
Very true Chris. Although in fairness, the build itself is pretty straight forward as it's all 90 degree cuts & butt joints. Just takes a while. Stepped expansion also has its uses for mugs like me, who have no tools beyond a blunt 35 year old hand-saw inherited from my grandfather. 😉 Nothing like as good as the Austin of course, but not bad. I wouldn't want to try shifting a pair around much though! The 208ESigma box is bad enough!
I remember a classic piece of TC understatement for a doubled version: "it'll be very heavy." Yeah, that's one way of putting it. 😉
I remember a classic piece of TC understatement for a doubled version: "it'll be very heavy." Yeah, that's one way of putting it. 😉
planet10 said:
Okay, now that looks pretty interesting... glad to know there is another option I hadn't read about yet. Regarding parts count vs. angled cuts, for me, I think the angled cuts are probably the easier of the two to deal with.
Some searching turned up a couple of threads:
166es-r in a austin a166 & construction ?
FullRangeDriver Forum » Austin Horn
Looks like the CC needs to shrink slightly for the 166ES-R, similar to 168 Sigma, sound right? So, it should be OK to start with the original plans and add filler blocks to the CC later. Ron suggests it should be hand-tuned.
Is there any stuffing / damping in the Ron horns? From what I can tell, there isn't, just a little bit inside the CC. I'm also wondering about the need for the rear wedge... I see photos for at least one pair built without the wedge.
Also, I wonder how critical the supra-baffle is to the sound... if there's room there to change the baffle shape without screwing up the sound.
hifiZen said:
Yes, yes, yes...
Plans are a bit sketchy. Windows wiped out all of Ron's original drawings, and retooling them hasn't hit the top of my queue yet. What there is is on the Frugal Horn site.
dave
Well, I'm half decent with AutoCAD (used to do a fair bit of architectural CAD work, still own a copy of acad 2k). No promises about being speedy, but I'll start with those PDF drawings and see what I can get done over the Thanksgiving break.
Ok!
I have a report on a FE166 metronome pair I put together this weekend...
Built exactly per the plan on the frugal-horn site (thanks!)
Included BSC circuit as recommended.
Cabinets went together fairly easily with lots of clamps (despite the weird angular shape...)
Sound Impressions:
**DISCLAIMER: the cabinet has not been stuffed, or lined in any way- naked plywood inside, no mods on drivers**
Soundstage:
Very VERRRRY good imaging- I am sort of a newcomer to hi-fidelity speaker systems, I previously have been using only high end headphones, where the image is placed between your ears. Before I built these, my idea of loudspeaker imaging was... "thats off to the right" or "thats off to the left", but with the metronomes, there is a continuous space between the speakers, and possibly stretching out beyond a foot or two, in which the performers and instruments occupy their own little spaces... COOL! It should be noted, however, that the "sweet spot" is TINY!
High end:
I dont feel any need for a tweeter- cymbals sound awesome!
Bass:
Ok, heres the deal... (Note: They need the "Loudness" switch on my old SS reciever to be in the "on" position, or else they sound thin...) These speakers model down to 40Hz, and I think they get there- very low bass for this little driver, so in that, I'm impressed - however, when you drive them to much more than a whisper volume, the speakers begin to sound flabby; to achieve significant volume, the "loudness" needs to be turned off- but then the thin sound returns. Also, I notice that when driven, the cones really move! (I think more than the Xmax parameter says they should) Is it possible that I have unrealistic SPL expectations for this system? They definitely cannot keep up with my 2-way Klipsch home theater towers (spl or bass wise)...
Midrange: This is the big hitch... Very "shouty" upper mids! I don't have too much test equip- but I would say that somewhere slightly below 1khz, there is a huge peak, and it is a little distracting/ fatiguing... any suggestions? please?
Otherwise, very detailed sound- much clearer than the klipsch- (and I think they would be, even without the shoutiness)
In general:
Some stuff sounds great on these- small ensemble vocal music and jazz in particular. at low volume, even Portishead sounds great (a big surprise, with all the bass), The imaging blows me away- but most Rock sounds nasal, and lifeless... (probably because of the big midrange peak) In rock, the drums seem to lack "punch", and the bass guitar (while present) sounds distant and dry... This may be, again, due to the bass/ spl tradeoff- they have difficulty filling the room with sound...
P.S. they're big, but they look cool!
I have a report on a FE166 metronome pair I put together this weekend...
Built exactly per the plan on the frugal-horn site (thanks!)
Included BSC circuit as recommended.
Cabinets went together fairly easily with lots of clamps (despite the weird angular shape...)
Sound Impressions:
**DISCLAIMER: the cabinet has not been stuffed, or lined in any way- naked plywood inside, no mods on drivers**
Soundstage:
Very VERRRRY good imaging- I am sort of a newcomer to hi-fidelity speaker systems, I previously have been using only high end headphones, where the image is placed between your ears. Before I built these, my idea of loudspeaker imaging was... "thats off to the right" or "thats off to the left", but with the metronomes, there is a continuous space between the speakers, and possibly stretching out beyond a foot or two, in which the performers and instruments occupy their own little spaces... COOL! It should be noted, however, that the "sweet spot" is TINY!
High end:
I dont feel any need for a tweeter- cymbals sound awesome!
Bass:
Ok, heres the deal... (Note: They need the "Loudness" switch on my old SS reciever to be in the "on" position, or else they sound thin...) These speakers model down to 40Hz, and I think they get there- very low bass for this little driver, so in that, I'm impressed - however, when you drive them to much more than a whisper volume, the speakers begin to sound flabby; to achieve significant volume, the "loudness" needs to be turned off- but then the thin sound returns. Also, I notice that when driven, the cones really move! (I think more than the Xmax parameter says they should) Is it possible that I have unrealistic SPL expectations for this system? They definitely cannot keep up with my 2-way Klipsch home theater towers (spl or bass wise)...
Midrange: This is the big hitch... Very "shouty" upper mids! I don't have too much test equip- but I would say that somewhere slightly below 1khz, there is a huge peak, and it is a little distracting/ fatiguing... any suggestions? please?
Otherwise, very detailed sound- much clearer than the klipsch- (and I think they would be, even without the shoutiness)
In general:
Some stuff sounds great on these- small ensemble vocal music and jazz in particular. at low volume, even Portishead sounds great (a big surprise, with all the bass), The imaging blows me away- but most Rock sounds nasal, and lifeless... (probably because of the big midrange peak) In rock, the drums seem to lack "punch", and the bass guitar (while present) sounds distant and dry... This may be, again, due to the bass/ spl tradeoff- they have difficulty filling the room with sound...
P.S. they're big, but they look cool!
GratefulTony said:
Tony,
I can think of a few reasons your Met's bass is MIA. First, you say you're using the Fostex FE166's. I don't remember a design for the 166's, only the 167's. The lower Q of the 166 would result in less bass, especially with a SS amp ahead of them. A resistor in series with teh + lead to the driver might help resotre some bass (at the expense of burning some power in the resistor). Scottmoose could probably advise if a port change would be advised to adapt the 166 to the 167 cabinet.
If the drivers are brand new, you'll need to give them lots of time to break in before they sound like they should. The Hemp Acoustics drivers in my Met's took MONTHS to fully break in, and I nearly gave up on them while I was waiting! They sound much smoother now, it was worth the wait.
The lack of damping in the cabinets may be adding to the midrange 'shout'. For mine, I bought a yard of fine netting at the fabric store (like for a bridal veil), and cut a tapered 'sock' the rough size of the cabinet interior, and long enough to reach a bit below the driver. I sewed up the sock with heavy thread, filled it with teased out fiberfill, and closed the bottom with a drawstring so I can open it for adjustment. I can get the sock in and out through the driver hole. A string is stapled inside the cabinet a little below the driver to hold up the sock. I used something under a pound of fiberfill per speaker (roughly 0.5 lb/ft^3, which IIRC is MJK's recommended starting point in his MLTL designs) and I have never felt the need to go play with the stuffing after that. The cabinet is otherwise unlined and unbraced.
One last thing, your photo shows the speakers well out into the room. You may want to try them closer to the wall. If that restores some of the bass, you may need to either keep the near-wall placement, or modify the BSC to your taste.
They are good looking speakers, aren't they? 😀
Bill
Hmmm... I see... I guess using the right driver would help ;-)
I guess I was under the impression that the FE166 and FE167 were basically the same speaker~ just that the 167 was magnetically shielded and the 166 wasn't... whoops! (should've checked the specs!)
Would any cab modifications be able to properly salvage this, or would I just be better off getting the right drivers?
I guess I was under the impression that the FE166 and FE167 were basically the same speaker~ just that the 167 was magnetically shielded and the 166 wasn't... whoops! (should've checked the specs!)
Would any cab modifications be able to properly salvage this, or would I just be better off getting the right drivers?
You can artifically raise the Qe & Bl factor of your 166s by adding a 4 - 5ohm resistor in series with the driver. That should bring the bass up, and take down some of the midrange that's bothering you. You don't say what your amp is, but with the exception of some class T amps, and Nelson Pass's Zen & First Watt designs, this is not a driver that likes low output impedance solid-state amplifiers at all, without some series resistance to reduce it's damping factor. This will reduce the efficiency, but rebalance the sound.
The internals require some damping -at the very least, line the rear panel from the top to just below the driver to prevent any reflections from the rear wall coming back out through the cone.
The cabinets are specifically intended for near-wall placement, so try experimenting with the position a bit.
Finally, the 166 is known for a somewhat forward midrange. Phase plugs will help here, as will some basket damping etc.
For future reference, the FExx6E and FExx7E series units all have very different parameters -it's more than just shielding. The up-side is even with series resistance added, the large motor of the 166 will provide good detailing, so it's not a disaster.
The internals require some damping -at the very least, line the rear panel from the top to just below the driver to prevent any reflections from the rear wall coming back out through the cone.
The cabinets are specifically intended for near-wall placement, so try experimenting with the position a bit.
Finally, the 166 is known for a somewhat forward midrange. Phase plugs will help here, as will some basket damping etc.
For future reference, the FExx6E and FExx7E series units all have very different parameters -it's more than just shielding. The up-side is even with series resistance added, the large motor of the 166 will provide good detailing, so it's not a disaster.
Ok, so you're saying that I could get good results by adding series resistance to alter the Q of the system- and it would be unnecessary to just swap out the drivers?
(The amp is less than ideal, BTW, its just an old sony ss receiver from the 80's)
I will definitely add some damping also...
Thanks!
-Tony
(The amp is less than ideal, BTW, its just an old sony ss receiver from the 80's)
I will definitely add some damping also...
Thanks!
-Tony
GratefulTony said:
Yup. The damping will help too. Then modify hell out of the drivers.
The amp should do OK for now. No, it's not ideal, but with the series R in place it should do a passable enough job.
GratefulTony said:
Keep in mind that the Fostex is going to show up every wart your receiver has, and that with the efficiency of the driver will be operating where it is at its worst. The series R will not only help rebalnace things but will push the receiver into a bit better opperating zone. Prepare to be gobsmaked when you start borrowing amps to try out... 2-15 watts of tube, T-amp, or high output impedance SS should be top of your list.
dave
Ok, so as for modding the driver, I should be thinking things like:
-phase plugs
-ENABL
-basket damping
-series resistance
-polyfill beneath whizzer cone?
and for the cabinet, I should be:
-adding some internal damping in the top of the enclosure, and especially behind the driver
-moving them closer to the wall
(and thinking about trying out some better amps)
Q: If I were to switch to a different amp, would I need to remove any series resistance to bring the Q back down to normal? or should I be able to leave it in place?
-I am thinking about trying one of the 41Hz T-amp kits on for size~ how much power would I need to get full spl from these speaks? Will 5W do it? or should I think about the higher power models? I see that THD goes up with output drive on many versions, including the commercial T-amp, so though it may claim to be capable of 15W, those higher powers may not sound as clear...
So: with the adjusted Q, will the drivers be able to reach a healthier volume without so much excursion?
As a physics student, I guess I am obligated to understand what is going on here, so let me give it a shot:
-With the lower Q of the FE166, the resonance phenomena occur over a wider frequency range; not necessarily properly tuned for this cabinet; the driver may be happy to provide a lot of excursion for a little drive at a frequency where the cab is also attempting to bolster response, so the cone is free to flap in the wind unfettered, possibly providing too much bass where the resonance of the cab, and the resonance of the cone overlap, overloading the cone and suspension (maybe contributing to what I described above as a "flabby" sound), but not necessarily using the cab and driver in their fullest synergy to produce proper response over a range; but with the higher Q of the adjusted circuit, or the FE167, the resonance phenomena is limited to a smaller range about f0, and the resonance of the cab should fall below, and not overlap with this resonance, allowing for LESS bass response in some freq. bands, but more in others, along with less speaker excursion for certain freq.s and thus the ability to apply more drive to attain more broadband bass without overdrive at resonance...
right track? or am I completely wrong?
I'm new to all this thiele-small stuff... but learning...
(P.S. Ive really been learning a lot here- thanks a ton everyone!)
-phase plugs
-ENABL
-basket damping
-series resistance
-polyfill beneath whizzer cone?
and for the cabinet, I should be:
-adding some internal damping in the top of the enclosure, and especially behind the driver
-moving them closer to the wall
(and thinking about trying out some better amps)
Q: If I were to switch to a different amp, would I need to remove any series resistance to bring the Q back down to normal? or should I be able to leave it in place?
-I am thinking about trying one of the 41Hz T-amp kits on for size~ how much power would I need to get full spl from these speaks? Will 5W do it? or should I think about the higher power models? I see that THD goes up with output drive on many versions, including the commercial T-amp, so though it may claim to be capable of 15W, those higher powers may not sound as clear...
So: with the adjusted Q, will the drivers be able to reach a healthier volume without so much excursion?
As a physics student, I guess I am obligated to understand what is going on here, so let me give it a shot:
-With the lower Q of the FE166, the resonance phenomena occur over a wider frequency range; not necessarily properly tuned for this cabinet; the driver may be happy to provide a lot of excursion for a little drive at a frequency where the cab is also attempting to bolster response, so the cone is free to flap in the wind unfettered, possibly providing too much bass where the resonance of the cab, and the resonance of the cone overlap, overloading the cone and suspension (maybe contributing to what I described above as a "flabby" sound), but not necessarily using the cab and driver in their fullest synergy to produce proper response over a range; but with the higher Q of the adjusted circuit, or the FE167, the resonance phenomena is limited to a smaller range about f0, and the resonance of the cab should fall below, and not overlap with this resonance, allowing for LESS bass response in some freq. bands, but more in others, along with less speaker excursion for certain freq.s and thus the ability to apply more drive to attain more broadband bass without overdrive at resonance...
right track? or am I completely wrong?
I'm new to all this thiele-small stuff... but learning...
(P.S. Ive really been learning a lot here- thanks a ton everyone!)
GratefulTony said:
yes, yes, yes.
The original mod used very low density foam in a strip supporting the top edge of the whizzer (furnace filter foam to be specific). Whether this is required once the driver has been EnABLed has yet to be determined.
Series R is very much amp, room, and placement specific. You should make sure it is easily accessible.
For example. We strated playing with added R to FE126 in Brynn. With the Paramours in Chris' small room the recommended 5 ohms was way too much, 2 was better (we only tried 0, 2, 5 ohms). Chris is now installing a double post terminal cup to make it easy to play with different R.
dave
GratefulTony said:right track? or am I completely wrong?
I'm new to all this thiele-small stuff... but learning...
Basically what's happening is the FE166E, being a low Q unit (i.e. it has a light cone, stiff suspension & a high-power motor etc.) is naturally well-damped (arguably overdamped) in the LF. Now, if you combine that with an amplifier with a low output impedance (high Damping Factor), the amp can't help correct for this damped LF behaviour / low driver Qts. High DF amps work best with high Qt drive units, which are underdamped in the LF. Conversely, a high output impedance (low DF) amplifier will work best with a low Qt driver and / or system where their own relatively underdamped response in the LF will help raise the overdamped behaviour of the drive unit in the same region. It's all about getting the balance right.
Adding series R will artificially raise the Qt (actually the Qe and Bl) of the drive-unit, which has the same effect as lowering the DF of your amplifier. That amp will need changing at some point as it's not the last word in sound-quality, but at least with series R in place you'll be getting some well-rounded bass. At present you'll have a decreasing response below the driver mass-corner with a peak at Fc -worst of both worlds.
Scott
Ok, well, at least I tried 🙂
so, its less a product of the Q itself, and more a product of the LF damping that determines driver Q... I cant remember the equations for damped harmonic oscillation off the top of my head (shame on me!)- but this is starting to sound familiar-
adding the series resistance will compensate for the high damping factor of the SS amp- and consequently, change the Qts
-or something...
I will be able to test this weekend- will post back with results-
...in the meantime, exams!!
so, its less a product of the Q itself, and more a product of the LF damping that determines driver Q... I cant remember the equations for damped harmonic oscillation off the top of my head (shame on me!)- but this is starting to sound familiar-
adding the series resistance will compensate for the high damping factor of the SS amp- and consequently, change the Qts
-or something...
I will be able to test this weekend- will post back with results-
...in the meantime, exams!!