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Hi,
I've finished a new pair of Onken style speakers designed for HT. My first project uses the FE127E. I decided on a 6L box size to reach a hoped-for 80Hz cut-off (where the HT sub should take over). Dimensions were chosen based on convenient lumber sizes and to suit the final location I have in mind. I also made some aesthetic choices in terms of the shape & size and number of port vents.
I've had a lot of inspiration and help from the forum (such as Dave, Chris, Bob and others), the last thread I created in this regard is at: http://www.diyaudio.com/forums/showthread.php?s=&threadid=137666&perpage=25&pagenumber=1
Since this speaker is designed as an HT satellite I've named it after one !
And in case anybody likes the design I'll post my drawings (but do go and see what they're doing at planet10 where there is a wealth of design information and perhaps something more suited for your application)
[dear moderator, let me know if this is out-of-line, but I'm starting this new thread because the old one has a generic subject title that will soon get lost in the mists of time...]
EDIT: October 2014: I'm no longer using the FE127E (which is obsolete) but have moved on to using a Mark Audio driver, the CHN-70 - details start at Post 144.
I've finished a new pair of Onken style speakers designed for HT. My first project uses the FE127E. I decided on a 6L box size to reach a hoped-for 80Hz cut-off (where the HT sub should take over). Dimensions were chosen based on convenient lumber sizes and to suit the final location I have in mind. I also made some aesthetic choices in terms of the shape & size and number of port vents.
I've had a lot of inspiration and help from the forum (such as Dave, Chris, Bob and others), the last thread I created in this regard is at: http://www.diyaudio.com/forums/showthread.php?s=&threadid=137666&perpage=25&pagenumber=1
Since this speaker is designed as an HT satellite I've named it after one !
And in case anybody likes the design I'll post my drawings (but do go and see what they're doing at planet10 where there is a wealth of design information and perhaps something more suited for your application)
[dear moderator, let me know if this is out-of-line, but I'm starting this new thread because the old one has a generic subject title that will soon get lost in the mists of time...]
EDIT: October 2014: I'm no longer using the FE127E (which is obsolete) but have moved on to using a Mark Audio driver, the CHN-70 - details start at Post 144.
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Thanks for the positive feedback...
The sub is still on the drawing board. I am leaning towards something based on the SDX-7 (again, inspiration coming from Planet10). I have to decide if I want a floorstander for the front which will be based on the Moon + sub, or if I want more Moon's and a separate sub. What's your advice ?
I'll throw in a another photo of the Moon...
The sub is still on the drawing board. I am leaning towards something based on the SDX-7 (again, inspiration coming from Planet10). I have to decide if I want a floorstander for the front which will be based on the Moon + sub, or if I want more Moon's and a separate sub. What's your advice ?
I'll throw in a another photo of the Moon...
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Bigun said:
A couple of thoughts, but in the spirit of full disclosure, I've become far less of a fan of the HT experience as time passed by; wherein the full body immersion, sensory overload and frequently distorted perspectives of exaggerated sound and visual effects swamp the actual art of story telling, so I'll admit to a bit of a jaundiced attitude on the subject.
So... depending on how "extremis" you want to get, a single SDX7 / FE127E per side would certainly be a great combination start. Assuming your HT processor / receiver has appropriate bass management, you could even experiment with the "need" for a separate dedicated LFE woofer. (as in NOT)
i.e. When I last played with my Denon HT receiver ( at least 3 yrs ago - several lifetimes in this niche), I'd set the mains to small, which would feed the LF signals from those channels as well as the "LFE" information to the sub line level out. Of course the problem here is that you loose stereo separation of "regular" LF information from the generally non directional LFE "stuff"
If the room allows placement for dispersion, you could easily side mounting the woofers in an enclosure with the same footprint and profile as the Moonkens (sorry, but how could I resist) . They could be built either as a separate enclosure, or integrated into a single full height unit. (see the Planet10 Tysen design for such a configuration with a smaller wide band driver, the FF85K)
If your circumstances require the woofers to be forward firing, it would take a bit more aesthetic creativity to fit the SDX7 into the same profile cabinet, but I'm sure you could come up with something workable.
Parts to achieve XO dividing networks for the L&R mains channels at your chosen frequency won't be inexpensive, and there is the substantial difference in sensitivities between the FE127 and SDX7 to contend with.
Bi-amping, with either active or passive line level XO`s would be the ideal solution; if your processor or receiver has line level outs for those channels, you could use any adequately powered SS amp to power the woofers. Alternatively, there are any number of sub-woofer plate amps that include all the appropriate circuitry, but be advised that without modification, the XO stage of these would become the weakest link in your system.
Do any current receivers allow for the flexible configuration of bi-amping the front channels by looping through an external XO, and using either a separate power amp, or a couple of unused internal surround channels. I`ve seen some rigs with as many as 7.1 channels, who really needs 4 channels of rear and center surround
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I may be going in circles, but it seem that there's no need for such a thing as a Fonken-woof then...
If you have a good Fonken then it goes down to at least 80Hz (and likely lower). So it already produces sound covering all the directional frequencies. You only need an additional driver for where the Fonken leaves-off, which is for non-directional frequencies. In which case you don't need stereo, you can use a single sub-woofer optimally designed and placed (which may mean not underneath your Fonken with all the dimensional restrictions).
The Tysen (can you post a link to this design?) is a sealed box, so the FR driver doesn't go down as low as 80Hz so it needs to have the 2nd driver in the same box because the XO sits somewhere higher.
And I go in yet more circles, because it seems you don't need the regular Fonken either...
If you are going to have sub-woofer (either single or stereo) you only need your Onken to go down to 80Hz which needs only 6L for a BR which brings me back to the Moon-Onken
If you have a good Fonken then it goes down to at least 80Hz (and likely lower). So it already produces sound covering all the directional frequencies. You only need an additional driver for where the Fonken leaves-off, which is for non-directional frequencies. In which case you don't need stereo, you can use a single sub-woofer optimally designed and placed (which may mean not underneath your Fonken with all the dimensional restrictions).
The Tysen (can you post a link to this design?) is a sealed box, so the FR driver doesn't go down as low as 80Hz so it needs to have the 2nd driver in the same box because the XO sits somewhere higher.
And I go in yet more circles, because it seems you don't need the regular Fonken either...
If you are going to have sub-woofer (either single or stereo) you only need your Onken to go down to 80Hz which needs only 6L for a BR which brings me back to the Moon-Onken
For surround sound, in partial circles at least, go you must?
Even for 2.0 musical listening only, and with mains that can extend as low as the neighborhood you're discussing, there are still lots of good reasons to consider dual woofers / distributed bass .
Yes, the Tysen incorporates a bass driver in each cabinet, as the FF85K is crossed over at approx 300Hz, IIRC.
Dave, care to elaborate on that?
Even for 2.0 musical listening only, and with mains that can extend as low as the neighborhood you're discussing, there are still lots of good reasons to consider dual woofers / distributed bass .
Yes, the Tysen incorporates a bass driver in each cabinet, as the FF85K is crossed over at approx 300Hz, IIRC.
Dave, care to elaborate on that?
Re: JX92S?
Do you have the JX92S already?
If by "this", you mean a derivation on the Fonken (Prime ), who knows for sure - but I'd be inclined towards the driver for which this enclosure was optimized ( i.e. FE127E) , and for which there is a fair amount of anecdotal evidence that it works quite well indeed.
Of course, several years experience with this particular combination could well be taken to color my own opinion, but there are other builders as well....
boudy said:
Do you have the JX92S already?
If by "this", you mean a derivation on the Fonken (Prime ), who knows for sure - but I'd be inclined towards the driver for which this enclosure was optimized ( i.e. FE127E) , and for which there is a fair amount of anecdotal evidence that it works quite well indeed.
Of course, several years experience with this particular combination could well be taken to color my own opinion, but there are other builders as well....
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Re: Re: JX92S?
Yes I already have them and like them better than most other FR's I've heard to date. I have 120A's in my desktop OBs and enjoy them as well, but otherwise I'm not a Fostex fan.
I know that the specifics of the design have to change to accommodate different drivers, I'm wondering if the general approach is feasible.
Anyone have an Onken calculator handy?
chrisb said:
Yes I already have them and like them better than most other FR's I've heard to date. I have 120A's in my desktop OBs and enjoy them as well, but otherwise I'm not a Fostex fan.
I know that the specifics of the design have to change to accommodate different drivers, I'm wondering if the general approach is feasible.
Anyone have an Onken calculator handy?
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Most likely I'm wrong on this count, but you don't need an 'Onken' calculator. It's really the same thing as BR. At least when I use a BR calculator to review other people's Onken speakers, their designs match up with the BR results.
Try this: http://micka.de/org/en/index.php#ideal
The idea is that you use long thin ports. In the calculator I've linked above you can enter dimensions for your 'own box'. You can adjust them to get the response curve you are looking for (i.e. mostly flat). People have all sorts of guidelines, like a 'real Onken' needs ports that are at least 35cm long. I say phooey - so long as the port has enough 'resistance' to the air-flow it will dampen the BR resonance which is the hallmark of the Onken. Shorter ports just mean they have to use high aspect ration openings (long and thin). This forces the air into contact with a much larger surface area along the port and it's this that provides the air flow resistance.
Now having said that, the other guys (Dave, Chris etc.) have forgotten more about Onken design than I've learned...
Try this: http://micka.de/org/en/index.php#ideal
The idea is that you use long thin ports. In the calculator I've linked above you can enter dimensions for your 'own box'. You can adjust them to get the response curve you are looking for (i.e. mostly flat). People have all sorts of guidelines, like a 'real Onken' needs ports that are at least 35cm long. I say phooey - so long as the port has enough 'resistance' to the air-flow it will dampen the BR resonance which is the hallmark of the Onken. Shorter ports just mean they have to use high aspect ration openings (long and thin). This forces the air into contact with a much larger surface area along the port and it's this that provides the air flow resistance.
Now having said that, the other guys (Dave, Chris etc.) have forgotten more about Onken design than I've learned...
Bigun said:
Depends on the alignment you're shooting for.
True, though some folks believe it's a form of TL.
Well, you ideally use at least (8) vents (the original had (13) metal tubes) that ideally sum their areas to = driver Sd, with 0.75*Sd the acceptable minimum.
No, the vents must be < ~35 cm long to keep vent pipe harmonics reasonable. It's this spec that keeps most modern drivers from being suitable for proper Onken loading due to not having a large enough Vas.
A 'real' Onken's 'claim to fame' is its massive vent system which has a high acoustic efficiency not unlike some PR vent systems, while the more resistive vents that rely on friction and/or damping that Dave prefers does the opposite in that it reduces vent efficiency, so an apples n' oranges comparison with each having its own merits/trade-offs.
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