Help building a Klipsch and other speaker (1 Viewer)

[Henry_W]

As few facts as possible - I am building a center with older Klipsch tweeter (K-77), Klipsch Mid (K-55-v with K400 lens), Klipsch type 'E' crossover and a couple of small woofers (I have just purchased a couple of Fostex FE168Z for the first go round). It is apparently a tough task for a newbie but it is somethng I want to try - an attractive center channel that fits the traditional top of an RPTV and has a tone and timbre match to sides and mains. I can't seem to rouse much interest on most DIY boards, so most of my education is intensive review of archived messages.

My biggest issue is the woofers (especially with the ability for the horns to stand alone). Where I stand - a box that I have designed with both WINISD and Unibox (just can't rectify the different port dimensions suggested by each) that will have 42L Vb (inclusive of internal components) - with a preference for a rectangle slot in the rear. The crossovers - Reciever managed below 80hz to the sub and crossover at 700hz to the mid. Overall box efficiency should be around 96db.

Am I on the right path? any ideas would be greatly appreciated. Explicit identification of flaws in my approach (like depending on unibox and isd) will not damage my ego beyond repair...

 

[Greg Monfort]

First things first, have you queried the guys on the HE or Klipsch forums? And if so, did you get any useful info? What are your other speakers you're trying to blend to?

GM

 

[Henry_W]

Yes - checked at both places. HE got no responses on two posts (makes me wonder if my newness offered too large an opportunity for education). The Klipsch folks were as helpful as they always are and helped me to this point - some great guys at Klipsch tech support provided me with the existing woofer T/S prams that are with the crossover. The biggest issue is box building - which few of the Klipsch folks could help since they tend to work with existing boxes. One other DIY site seemed intent on pointing me to a single driver setup, with little input on my project - so here I am - somewhat self educated with a high probability of error. I am resorting to trial and error, mainly because I get stuck on an idea until I discover the answer.

I have an HT/Music set up. Tubes are with my brother (as well as my Klipschorns) waiting for when I build a room for them - after seventeen years he may feel like he owns them! I am very pleased to date with the setup (except the center) for both HT/Music. I have Heresy front and sides with infinity rears supplemented by an SVS 20-39PCi for the LF. The RPTV and speakers are in a wall to wall builtin cabinet/bookshelf (rather attractive if I say so myself). The crossover, Tweeter and mid (squawker) drivers and horn lens are from Heresy and match my existing speakers. The delimma is the 12 inch woofer used by the heresy doesn't fit that top of TV scenario - also, being rear projection, I have little concern with shielding if the speaker is on top. The Heresy SPL is 95db.

The crossover to the mid is at 700hz. With the reciever managing the LF below 80hz to the sub, I have looked at tuning the Fostex speakers to 65hz to cover the lowest freq I expect from the center and keeping a fairly flat response through the 700hz crossover point (at around 97db in parallel). As a full range, I may well be overpaying for freq response I won't use, but in my mind I an paying for the efficiency and a decent SPL to the tuning point.

I currently plan on a single rectangle vent in the back if I can keep the box far enough from the wall. 42l includes all interior stuff including vent.

Whew - sorry about the length here Greg, but you have been so useful to other folks I though I would give you as much as I thought fit. Thanks for your thoughtful response..

 

[Greg Monfort]

>My biggest issue is the woofers (especially with the ability for the horns to stand alone). Where I stand - a box that I have designed with both WINISD and Unibox (just can't rectify the different port dimensions suggested by each)
====
I have no faith in either WRT vents based on others published sims. Haven't checked their cab Vb accuracy. I use BoxPlot in most cases since it mirrors the 'accurate enough' results I got with the early Margolis/Small HP calculator program, and MK's MLTQWT spreadsheet for tower designs since his has a much better handle on what the stuffing's doing than the rules-of-thumb formulas I developed over the years.
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>Yes - checked at both places. HE got no responses on two posts (makes me wonder if my newness offered too large an opportunity for education).
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Probably due to the subject matter. Most of the regular posters are like me in that any post on that forum referencing anything smaller than a fridge with 500Hz horns perched on top don't get past our filtered retinas. Not to mention that a theater horn loaded stereo system don't need no stinkin' imaging/soundstaging destroying CC.
See, all you have to do is mention HE and I put on my 'game face'.
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> The Klipsch folks were as helpful as they always are and helped me to this point - some great guys at Klipsch tech support provided me with the existing woofer T/S prams that are with the crossover.
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And they are?
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>One other DIY site seemed intent on pointing me to a single driver setup, with little input on my project
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Hey! Works for me! Oops, another 'game face'. Anyway, they have their HT applications, and can be excellent ones within their limitations, just not the Hot Ticket for yours.
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> - so here I am - somewhat self educated with a high probability of error. I am resorting to trial and error, mainly because I get stuck on an idea until I discover the answer.
====
Well, this makes us 'brothers in arms' then.
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>I have an HT/Music set up. Tubes are with my brother (as well as my Klipschorns) waiting for when I build a room for them - after seventeen years he may feel like he owns them!
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Hmm, this has the makings of a good pay-per-view event: "Horny brothers square off over the tube happy 17yr old Klipsch Belles in the opposing corners", or some such.
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> I am very pleased to date with the setup (except the center) for both HT/Music. I have Heresy front and sides with infinity rears supplemented by an SVS 20-39PCi for the LF. The RPTV and speakers are in a wall to wall builtin cabinet/bookshelf (rather attractive if I say so myself).
====
OK, just don't go too narcissistic on us. Is it DIY? Got any pics you can post?
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> The crossover, Tweeter and mid (squawker) drivers and horn lens are from Heresy and match my existing speakers. The delimma is the 12 inch woofer used by the heresy doesn't fit that top of TV scenario
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Why?
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- also, being rear projection, I have little concern with shielding if the speaker is on top. The Heresy SPL is 95db.
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Yep, OK.
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>The crossover to the mid is at 700hz.
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Slope? Any shelving, notching, etc.?
====
> With the reciever managing the LF below 80hz to the sub, I have looked at tuning the Fostex speakers to 65hz to cover the lowest freq I expect from the center and keeping a fairly flat response through the 700hz crossover point (at around 97db in parallel).
====
Without specs for either the Fostex or Heresy 12" about all I can say at this point besides the earlier feeble attempts at humor is that assuming the Fostex is a 6" driver, then even if butted up against each other their useable -12dB response is ~700Hz, ergo with a 700Hz XO it's compromised from the get-go from a purely technical POV. How audible it will be in your app. I can't even hazzard a guess due to the in-wall design.
At the same time, using sidewiding dual 6"ers gives a good facsimile of a 12"er's polar response in the horizontal plane, but vertically they are obviously very different so will be somewhat tonally mismatched.
WRT Fb, the Fostex must have ~ the FR/GD as the Heresys in their matching passband, with ~the same impulse response, so does the Fostex have close to the same Qms/Qes?
Ideally, the tweeter horn needs to be between the mid/LF and the mid at the bottom next to the TV. Are the Heresy components laid out this way if you flop them upside down (couldn't find a pic sans grill), and what does this do to the overall vertical layout across the front?
====
>As a full range, I may well be overpaying for freq response I won't use, but in my mind I an paying for the efficiency and a decent SPL to the tuning point.
====
Hmm, ideally you need a driver with the same roll off slope as the 12" since it's probably part of the Heresy's total slope, so an additional inductor and it's electrical effects may need to be factored into the design.
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>I currently plan on a single rectangle vent in the back if I can keep the box far enough from the wall. 42l includes all interior stuff including vent.
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OK, any particular reason for a rectangular vent? For the moment I consider the 42L suspect.
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>Whew - sorry about the length here Greg, but you have been so useful to other folks I though I would give you as much as I thought fit. Thanks for your thoughtful response..
====
You're welcome! Yeah, I can get all the design work I want when I give it away. Oh well, if I didn't enjoy it I wouldn't do it. Anyway, I'm pretty much reduced to vicariously playing speaker builder through other's projects, at least for the time being.
GM

 

[Henry_W]

>>I have no faith in either WRT vents based on others published sims.
Fair enough - I am a beginner with no background, so your advice is most valuable.
>>See, all you have to do is mention HE and I put on my 'game face'.
Well done - just like being there.
>>And they are? (T/S on Heresy woofer K-22)
Fo=35hz, Fi=33.04hz, Re=6.9 ohms, Le=1 mh, SPL=93.28db, Qms=5.3, Qes=.446, Qts=.411, sd=.053 sqM, Xmax=4mm, Vas=.143 cuM, Pmx=100Watts, BL=14TM, no=1.33%, ni=1.06%, Vg=2.83V, Cms=359 uM/N
>>Well, this makes us 'brothers in arms' then.
You poor SOB - There is no twelve step program for us, yet..
>>OK, just don't go too narcissistic on us. Is it DIY? Got any pics you can post?
Yes it is DIY and is one of those rare carpentry projects where I am pleased with most all aspects. My profile says I cannot send attachments - another attempt to keep the niave away . I'll send private message with pics - I am especially proud of the Heresys that are set in the ceiling.
>>> The crossover, Tweeter and mid (squawker) drivers and horn lens are from Heresy and match my existing speakers. The delimma is the 12 inch woofer used by the heresy doesn't fit that top of TV scenario
====
Why?
Well, simply asthetics and what I want to do. Folks tend to tell me to get a full size (which I have tested and do like - although the sound is very focused to a single sweet spot) but I have this inate belief that this center can be made and made well. The full size would require wall cabinet modifications and I have already told you how proud I am of that! I also believe that it is more functional as a set top box.
>>Slope? Any shelving, notching, etc.?
Man, you got me there. I have no idea and if not included in any of the specs above, I don't have the foggiest idea where to get the info.
>>WRT Fb, the Fostex must have ~ the FR/GD as the Heresys in their matching passband, with ~the same impulse response, so does the Fostex have close to the same Qms/Qes?
Here are the Fostex (6.5in)T/S that I have found: Fs=60hz, Re=7.6ohms, Qms=4.53, Qes=.4, Qts=.37, Vas=15.27l, Xmax=1.25mm,no=1.18%, SPL=94db, P(music)=80Watts The Le is interpolated from a similar Fostex speced at .056 mH which could be a falicy that I have to review when I recieve units.
>>Ideally, the tweeter horn needs to be between the mid/LF and the mid at the bottom next to the TV. Are the Heresy components laid out this way if you flop them upside down (couldn't find a pic sans grill), and what does this do to the overall vertical layout across the front?
Layout is initially MHM where H=horns with Tweeter on top and mid on bottom closest to TV (a traditional Heresy setup - with the woofer below that in the standard cabinet). I have the width of the TV to play with - any replacement TV will be at a minimum just as wide - for speaker placement in baffle (since I have forced a height restriction based on my preferences). I can go so far as to turning the tweeter vertical and having an MSTM where S is the Squawker Mid horn.
>>Hmm, ideally you need a driver with the same roll off slope as the 12" since it's probably part of the Heresy's total slope, so an additional inductor and it's electrical effects may need to be factored into the design.
Now that is a real opportunity for me to learn something. I understand the doctor like Hmm but my mind turns to skiing when you mention slope. Hopefully some small info flow will give me a way to understand and incorporate this in the design without having to call Greg for help with every millimeter change...
>>OK, any particular reason for a rectangular vent?
Yep - I can construct a rectangle in the cabinet design with much more assurance than I can a round thingy. Getting a length of tube correct is no problem, but constucting one that is 4.45678934 in. diameter is another matter
>>For the moment I consider the 42L suspect.
Probably with good reason. I have SWAGed the space occupied by the lens, drivers, crossover and vent and hand calculated a couple of designs. I compared these to the box calc in winISD and it has matched (I have to add the internal stuff to the overall Vb for that calc to work - so when I say 42l the box sizing calc is 51l as an example). The SWAG is accurate enough to get me in the ballpark to validate that the box would work - or at least so I have led myself to believe (after all - if you want to play God you better be dang confident ).
Thanks again Greg - your insight, humor and overall good personness (that didn't pass spell check) is very much appreciated. Also, thanks for allowing me to publically display my ignorance....

 

[Greg Monfort]

>>And they are? (T/S on Heresy woofer K-22)

Fo=35hz, Fi=33.04hz, Re=6.9 ohms, Le=1 mh, SPL=93.28db, Qms=5.3, Qes=.446, Qts=.411, sd=.053 sqM, Xmax=4mm, Vas=.143 cuM, Pmx=100Watts, BL=14TM, no=1.33%, ni=1.06%, Vg=2.83V, Cms=359 uM/N

>>Well, this makes us 'brothers in arms' then.

>You poor SOB - There is no twelve step program for us, yet..
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Nope.
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>>> The crossover, Tweeter and mid (squawker) drivers and horn lens are from Heresy and match my existing speakers. The delimma is the 12 inch woofer used by the heresy doesn't fit that top of TV scenario
====
>Well, simply asthetics and what I want to do. Folks tend to tell me to get a full size (which I have tested and do like - although the sound is very focused to a single sweet spot) but I have this inate belief that this center can be made and made well.
====
You lost me. A Heresy as CC has a narrow 'sweet spot'?
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> The full size would require wall cabinet modifications and I have already told you how proud I am of that! I also believe that it is more functional as a set top box.
====
OK.
====
>>Slope? Any shelving, notching, etc.?

>Man, you got me there. I have no idea and if not included in any of the specs above, I don't have the foggiest idea where to get the info.
====
Klipsch tech should be able to give you all the particulars on the XOs.
====

>>WRT Fb, the Fostex must have ~ the FR/GD as the Heresys in their matching passband, with ~the same impulse response, so does the Fostex have close to the same Qms/Qes?

Here are the Fostex (6.5in)T/S that I have found: Fs=60hz, Re=7.6ohms, Qms=4.53, Qes=.4, Qts=.37, Vas=15.27l, Xmax=1.25mm,no=1.18%, SPL=94db, P(music)=80Watts The Le is interpolated from a similar Fostex speced at .056 mH which could be a falicy that I have to review when I recieve units.
====
Since they're full range, Le is low enough that it will affect the XO a bit, though how audible the difference will be compared to the Heresys.......
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>Layout is initially MHM where H=horns with Tweeter on top and mid on bottom closest to TV (a traditional Heresy setup - with the woofer below that in the standard cabinet). I have the width of the TV to play with - any replacement TV will be at a minimum just as wide - for speaker placement in baffle (since I have forced a height restriction based on my preferences). I can go so far as to turning the tweeter vertical and having an MSTM where S is the Squawker Mid horn.
====
Well, by my standards you're screwed then, since as I've already pointed out, even if the two Fostex were butted up against each other, they're only going to decently couple to ~700Hz, the XO point. Spread apart like you want is completely unacceptable from a good engineering POV unless you're willing to angle in the portions of the baffle they are mounted to. This will narrow up the sweet spot in both the horizontal and critical listening distance since they will be angled so that they combine at the primary listening position.
====
>>Hmm, ideally you need a driver with the same roll off slope as the 12" since it's probably part of the Heresy's total slope, so an additional inductor and it's electrical effects may need to be factored into the design.

>Now that is a real opportunity for me to learn something. I understand the doctor like Hmm but my mind turns to skiing when you mention slope. Hopefully some small info flow will give me a way to understand and incorporate this in the design without having to call Greg for help with every millimeter change...
====
The rate of a driver's, box, XO, roll off is its slope and is measured in dB/octave. A driver's or box is an acoustic one, and of course an electrical one is just that. 1st order is 6dB/octave, 2nd/12dB, 3rd/18dB, 4th/24dB, etc.. If a speaker was designed to combine a 2nd order acoustic slope to a 4th electrical, then we wind up with a 6th order (12+24 = 36dB/octave) combined slope.

What I was referring to is that say the heresy is 4th combined, but using the standard Klipsch on the Fostex it would only be 2nd, so there would be much more overlap between the Fostex/horns than between the Heresy's 12"/horn, audibly affecting tonal balance, ergo imaging/soundstaging. Adding an appropriate sized inductor would roll off the Fostex at ~the same point/slope as the 12", but its DCR would be added to the Fostex, increasing their Qts/lowering eff..

Not trying to be discouraging, but this probably isn't going to be a walk in the park, and without some good measurements or graphs from Klipsch could turn into a tweaker's nightmare. Factor in you've painted yourself into a corner WRT allowable speaker height......

Your best option appears to be to mount a Heresy sideways like the mains on the top shelf, with a spacer to tilt it down.
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>Yep - I can construct a rectangle in the cabinet design with much more assurance than I can a round thingy. Getting a length of tube correct is no problem, but constucting one that is 4.45678934 in. diameter is another matter
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??? You use standard tube sizes, whether cardboard/PVC/whatever, and adjust length to suit.
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>Probably with good reason. I have SWAGed the space occupied by the lens, drivers, crossover and vent and hand calculated a couple of designs. I compared these to the box calc in winISD and it has matched (I have to add the internal stuff to the overall Vb for that calc to work - so when I say 42l the box sizing calc is 51l as an example).
====
Good! When talking Vb, it should always be net.
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> The SWAG is accurate enough to get me in the ballpark to validate that the box would work - or at least so I have led myself to believe (after all - if you want to play God you better be dang confident ).
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Well, the only thing I'm confident of right now is that I don't have a magic bullet for you to hit your targeted goal.
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>Thanks again Greg - your insight, humor and overall good personness (that didn't pass spell check) is very much appreciated. Also, thanks for allowing me to publically display my ignorance....
====
You're welcome, it's what I'm here for, and hopefully lift the veil a bit for a peek into the realm of good audio reproduction.....

GM

 

[Henry_W]

Thanks again Greg - I have taken all to heart and only have the following comments or questions. Thanks for the time to help...
>>You lost me. A Heresy as CC has a narrow 'sweet spot'?
=======
Specifically with my wall cabinet the shelve over the TV does not allow me to angle a Heresy (which I do on my front L/Rs). The best I can figure is the sound is reflecting in odd ways and gives me a small sweet spot - this is not a speaker issue as I can best tell. A Heresy on the floor in front of TV sounds OK, but really is disorienting - I assume this is due to the distance from the front L/R.
========
>>Not trying to be discouraging, but this probably isn't going to be a walk in the park, and without some good measurements or graphs from Klipsch could turn into a tweaker's nightmare. Factor in you've painted yourself into a corner WRT allowable speaker height......
Your best option appears to be to mount a Heresy sideways like the mains on the top shelf, with a spacer to tilt it down.
==========
This is the info I needed - Your stuff on XOs and slope will help me tremendously in framing questions and learning more. This may well prove to not work as I would like, but I imagine the experimentation will be extremely educational. I will also need some decent measurement capabilities of my own as I move forward. Thanks for looking closely and educating.
======
>>Well, by my standards you're screwed then, since as I've already pointed out, even if the two Fostex were butted up against each other, they're only going to decently couple to ~700Hz, the XO point. Spread apart like you want is completely unacceptable from a good engineering POV unless you're willing to angle in the portions of the baffle they are mounted to. This will narrow up the sweet spot in both the horizontal and critical listening distance since they will be angled so that they combine at the primary listening position.
=========
I am not married to any specific layout. Instead of butting up the speakers, would you see any other forward facing set up (such as side by side woofers) that would offer an opportunity for improvement?
=====
Lastly - I do not have to have all speakers in the same box nor do I have to use the Fostex (if the Fostex don't work I can build a couple of small single driver full range speakers - horns of course - and then be able to participate in the single driver forums with the appropriate amount of self rightouesness ) Since the horns could stand outside of the box (as they do on many/most systems) there are other options I am considering as well.
Your answers will probably close the thread and I will start the initial build testing phases. If I approach anything near success I will be updating here for any of the interested. Outstanding conversations - I appreciate your patience.

 

[Greg Monfort]

>Specifically with my wall cabinet the shelve over the TV does not allow me to angle a Heresy (which I do on my front L/Rs). The best I can figure is the sound is reflecting in odd ways and gives me a small sweet spot - this is not a speaker issue as I can best tell. A Heresy on the floor in front of TV sounds OK, but really is disorienting - I assume this is due to the distance from the front L/R.
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OK, got the picture.
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>This is the info I needed - Your stuff on XOs and slope will help me tremendously in framing questions and learning more.
====
Yeah, since I only scratched the surface of this subject.
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> This may well prove to not work as I would like, but I imagine the experimentation will be extremely educational. I will also need some decent measurement capabilities of my own as I move forward. Thanks for looking closely and educating.
====
Glad to. In-walls, especially those with shelving, etc., are an acoustic nightmare to get even remotely decent FR across a soundstage of any width.
====
>I am not married to any specific layout. Instead of butting up the speakers, would you see any other forward facing set up (such as side by side woofers) that would offer an opportunity for improvement?
====
Not sure I follow. For good summing of multiple sources, whether two woofers, or a woofer and horn, there are physical limits as to how far apart they are based on the XO point/slope. Once you start compromising this, then the tonal balance changes/may audibly suffer. If you were building three speakers instead of trying to match one to two others, then some acceptable compromises can be made, such as a steeper XO slope, since they will all sound the same.
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>Lastly - I do not have to have all speakers in the same box nor do I have to use the Fostex
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I assumed as much, but the spacing issue means using smaller drivers, which causes other tonal compromises.
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> (if the Fostex don't work I can build a couple of small single driver full range speakers - horns of course - and then be able to participate in the single driver forums with the appropriate amount of self rightouesness )
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There ya go!
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> Since the horns could stand outside of the box (as they do on many/most systems) there are other options I am considering as well.
====
Well, they would need to be on a baffle to mimic the same diffraction issues as the others for best integration. DD/DTS don't recommend using all the same speakers just for a lack of a better suggestion.
I was pretty tired last night, but in retrospect, the 12"er will fit on the top shelf in a custom angled baffle cab with the same net volume as the Heresy, with a separate MT horn cab mounted to the bottom side of the shelf. The extra distance between the two Vs the Heresy's layout can be compensated for by adjusting baffle angles without any obvious audible difference.
Yeah, I like it, so you'll need a Heresy woofer. The horn cab should have the same width/depth/layout dims as the top portion of the Heresy, with as close as practical to the same materials/lining/grill. The woofer cab will have to be compromised of course, but starting with the height being so that the gap between the top of the cab and the top of the cavity is the same as for the Heresys to get the same general cavity resonances, ditto the depth to rear wall dims, then increase the width as required to get the correct net volume if the extra depth doesn't do it. Since the Heresys are on their sides, this isn't a big deal, and indeed may require baffle wings on the CC to get additional LF loading if it sounds anemic in the midbass/lower mids, comparatively speaking.
A bit of a woodworking challenge, and will look a bit strange, but it appears you're up to the task. WRT baffle angle, draw a side scale view of the Heresy's vertical on axis distance/angle, then do the same for the CC's woofer and horn cab so they hit the same point at the listening position to get their respective angles. They shouldn't be different enough to be any worse off axis than when you had one sitting down in front, and will probably be considerably better. You'll be able to use the Heresy XO as is, so all that will be left to do once installed is to use your pre-pro's time delay feature to rotate the CC back in time to match the mains.
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>Your answers will probably close the thread and I will start the initial build testing phases. If I approach anything near success I will be updating here for any of the interested. Outstanding conversations - I appreciate your patience.
====
My pleasure! I believe you'll be happy with this based on your other comments. If not, I disavow all knowledge of this thread since someone obviously hijacked my ID.
BTW, you or your wife really needs to add well stuffed teddy bears/car shaped pillows/whatever to ya'll's hobbies to help with those cavity resonances......
Now about those Fostex......
GM

 

[Henry_W]

Great - another alternative (I know I asked for it) . Are you related to my wife - she also seems to find ways for me to spend money.....
I may be silent for a while as I balance work and cabinet building - I will probably do at least two, most likely three designs, giving my thoughts on each result. Getting the 12" ahould be no problem - I'll probably end up with two like everything else.
Next - let's fix an overpriced, anemic BMW convertable audio system. I was thinking about the space and I believe we can turn the trunk (we could seal it - kind of worthless for anything else) into two folded horns with exits to the side of each seat. A tube amp (siesmicly mounted of course) with a retractable turntable should help me get advice both on the HE forum and the single driver forum. Keeping the cartridge tracking with 2.5 g will be a challenge, but WTH - life is boring without spending money on the impractical .

 

[Greg Monfort]

>Great - another alternative (I know I asked for it) . Are you related to my wife - she also seems to find ways for me to spend money.....
====
At least you appear to be able to afford to.....
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>Next - let's fix an overpriced, anemic BMW convertable audio system. I was thinking about the space and I believe we can turn the trunk (we could seal it - kind of worthless for anything else) into two folded horns with exits to the side of each seat. A tube amp (siesmicly mounted of course) with a retractable turntable should help me get advice both on the HE forum and the single driver forum. Keeping the cartridge tracking with 2.5 g will be a challenge, but WTH - life is boring without spending money on the impractical .
====
Well, it's all doable, and has been done by Chrysler in the '50s, except for the patented speaker design, but considering the Beemer's space limitations I assume you're joking. FWIW, 1-1.5g is the ideal tracking force. Higher/lower damages the grooves over time.

GM