AudioKinesis 1x12 Cab Part Two

[thudfromafar]

I remember looking into it, but don't remember saying that I'd definitely do it. If I did say that... oops... sorry!! Unfortunately yours has already been shipped.

This looks like one possible solution, but I wasn't able to find a source for it in the US.

Invalid Link Removed

There's about 1/4" clearance underneath the crossover board, so if we're really careful not to use screws that are too long, some beefy threaded inserts in the right place could probably hold the external tophat in place when we need it, and then when it's not in use the screws could be used to seal up the holes so that we don't have air leaks.

Thud, try your cab and see if it works for you as is. If not, let me know.

I think you said it wayyy back when the cab was still in design, iirc. Maybe you're right that it was just thrown out as a consideration, I don't remember exactly. No big deal. As long as there's some way for me to pole mount it... I just don't want to try and then kill the crossover or something so I'll need your help.

 

[DukeLeJeune]

I think you said it wayyy back when the cab was still in design, iirc. Maybe you're right that it was just thrown out as a consideration, I don't remember exactly. No big deal. As long as there's some way for me to pole mount it... I just don't want to try and then kill the crossover or something so I'll need your help.

Okay, someone just sent me a link to a US source for what looks like a very promising external tophat. I have ordered one to make sure it will do what we want and figure out the best way to install it.

 

[thudfromafar]

great

 

[Vic]

Okay, someone just sent me a link to a US source for what looks like a very promising external tophat. I have ordered one to make sure it will do what we want and figure out the best way to install it.

Can I see the link? I'm curious about the design.

 

[DukeLeJeune]

Can I see the link? I'm curious about the design.

Sure, here it is:

[Invalid or Expired Link Removed]

Credit (and a big THANK YOU) to 1n3 for finding it for me. I subsequently found a few others using the search term "mounting bracket" instead of "external top hat", but this one looks to me like it's the best made. I came across accounts of the cheaper ones cracking.

Once I've worked out how to mount the external top hat so that it can be mounted and removed fairly easily without leaving an air leak, I'll post the details. It will involve finding and marking the center of gravity, removing the woofer and ports and crossover board, and drilling some holes, at a minimum.

 

[Lee Barker]

Heavy points to Duke for (a) listening to a customer, (b) acknowledging the possibility of a change, (c) doing the homework (with help, yes,) to find a solution, and (d) thinking through the process.

Between musician and innovator, it just doesn't get any better than this!

 

[Vic]

Sure, here it is:

[Invalid or Expired Link Removed]
...
Once I've worked out how to mount the external top hat so that it can be mounted and removed fairly easily without leaving an air leak, I'll post the details...

Interestingly, that was the same one I found, but had the same question. I'll be very interested to see what you come up with on this.

 

[DukeLeJeune]

Thanks, Lee!

Interestingly, that was the same one I found, but had the same question. I'll be very interested to see what you come up with on this.

My initial thought on how to attach the external top hat is this: Threaded inserts (or maybe T-nuts or hurricane nuts) with a bit of glue so you're less likely to push 'em out by accident; screws no longer than necessary (so they don't bump the crossover board); and put the screws back in (perhaps atop neoprene washers) when the external top hat is removed.

 

[Vic]

My initial thought on how to attach the external top hat is this: Threaded inserts (or maybe T-nuts or hurricane nuts) with a bit of glue so you're less likely to push 'em out by accident; screws no longer than necessary (so they don't bump the crossover board); and put the screws back in (perhaps atop neoprene washers) when the external top hat is removed.

That seems like a good solution to me.

 

[Jazzdogg]

Thanks, Lee!



My initial thought on how to attach the external top hat is this: Threaded inserts (or maybe T-nuts or hurricane nuts) with a bit of glue so you're less likely to push 'em out by accident; screws no longer than necessary (so they don't bump the crossover board); and put the screws back in (perhaps atop neoprene washers) when the external top hat is removed.

Your solution seems quite viable.

If the crossover were mounted to a thin, e.g., 1/8" or 1/4" thick, plywood platform roughly the same size as the cabinet bottom, the platform could be installed after installation of the threaded inserts, effectively sealing the holes while protecting the crossover from inadvertent contact with mounting bolts.

Do you use the two-dowel method to locate the cabinet's center of gravity?

 

[primeVibe]

If anyone desires to hear it, only till Tuesday, possibly Wednesday, I have "Acoustic Friendly" Thunderchild (with rear tweeter). Duke was kind enough to let me and some friends audition it. I'm in Logan UT 84332, about 30 minutes south of Duke, 75 minutes NE of Salt Lake City.

At a show last December I heard standard TC excel with bass and Thorell jazz guitar. Friday and today it was interesting to hear TC perform so well with another Thorell jazz guitar and a superb Thorell flat top equipped with only a K&K 3-element bridge pickup. I highly recommend the AF/TC for such use. Today a friend/TB member and I compared AF/TC with Acoustic Image Clarus 2R to his highly regarded commercial combo amp ($1600 street value). He plays upright and has a collection of electric basses all or most of which he built. The AF/TC just killed his commercial amp (will remain nameless because he may list it for sale).

My home audio system employs a pure analog Trinaural processor with three front main speakers, L/R/C. The matched main speakers are very good and employ technology available in no production loudspeaker.

I AB'd the AF/TC with the center stereo speaker, compensating for the AF/TC's +6 dB sensitivity. The "transparency" in the AF/TC mid-range is exceptional, very close to a good electrostatic speaker (I know this is difficult to believe). The AF/TC dynamic punch is incredible, better than any known commercial stereo speakers. In the stereo speakers the drivers alone minus Xo cost $700 per channel, paper in oil capacitors throughout, reverse heat sensitive Dueland resistors, litz coil, caps matched to .01 mF, exotic enclosures, etc.

The AF/TC's dynamic punch and sound intensity made me prefer it at first. I had to switch the program material and really tune in to the fine points to eventually notice the spatial effects and certain other properties made me prefer my home audio speaker. The AF/TC is that good.

I don't know about low bass cutoff for home audio because I employ a custom mode-flattening distributed sub array designed by Duke. But I'd imagine AF/TC is effective to at least the mid-40s, which is completely respectable and livable. I haven't heard this, but everything points to two AF/TCs being great stereo monitors. Pull one or both out for gigs and you're good to go as long as no one is home expecting to use the stereo! At 95 dB they require only about 1/4 the power of most home speakers.

With the flat top guitar, Thorell and I both preferred the AF/TC over my home audio speaker because of the AF/TC's dynamic presence and sound intensity. I wrongly thought my home stereo speakers would be preferred.

AF/TC ain't cheap but I really wonder what could possibly touch it within it's power and low-bass envelope. I worked at 2011 NAMM and heard the German AER amps and listened to pros and decent amateurs for a long time at the Phil Jones exhibit. For bass I am thoroughly convinced even the most costly PJ can't touch AF/TC for sound quality.

For flat top I've heard the AER played for hours by two very good pros. AER sounds really superb with flat top (best commercial hi-volume gear) but til I AB them I'd chose the AF/TC (on flat top the AER is much closer call than PJ on bass). Again, I think the AF/TC's dynamic punch, sound intensity, and transparency make it preferable.

Lastly, we briefly heard my Bill Lawrence Telecaster through the AF/TC. I think Duke turned off the tweeter but he can chime in here. The Tele had a remarkable, pleasant presence, and same as all the other basses/guitars, the AF/TC reproduced nuance of playing style exceptionally well. We unfortunately had no distortion box to see how that performed. Duke downplays performance with electric solid body, but my first impression is that it works better than he will openly admit (he's always his own worst critic, an admirable and seldom seen trait).

 

[mikeddd]

Duke: Would threaded inserts work? Would allow for a bolt-on installation and wouldn't leak any air. Been lurking the thread; thought I'd throw my idea in. Good luck with it.

Mike

*edit*
Guess I should've read the rest of the thread before posting my groundbreaking idea. You came up with the idea two posts down from the one below. LOL! Carry on, please...nothing to see here...

Sure, here it is:

[Invalid or Expired Link Removed]

Credit (and a big THANK YOU) to 1n3 for finding it for me. I subsequently found a few others using the search term "mounting bracket" instead of "external top hat", but this one looks to me like it's the best made. I came across accounts of the cheaper ones cracking.

Once I've worked out how to mount the external top hat so that it can be mounted and removed fairly easily without leaving an air leak, I'll post the details. It will involve finding and marking the center of gravity, removing the woofer and ports and crossover board, and drilling some holes, at a minimum.

 

[Derek Kiernan]

*snip*

Lastly, we briefly heard my Bill Lawrence Telecaster through the AF/TC. I think Duke turned off the tweeter but he can chime in here. The Tele had a remarkable, pleasant presence, and same as all the other basses/guitars, the AF/TC reproduced nuance of playing style exceptionally well. We unfortunately had no distortion box to see how that performed. Duke downplays performance with electric solid body, but my first impression is that it works better than he will openly admit (he's always his own worst critic, an admirable and seldom seen trait).

I suspect that he engaged the rolloff filter, not turning off the tweeter. I've run guitars through the AF/TC with Bill Lawrence's new microcoils through low capacitance cables and gotten outstanding results.

I'm also strongly considering getting another AF/TC to use as a stereo setup as I like programmed music through it more than through my KRK studio monitors. We'll see what space and money I have when I move into a new apartment in a month or so. I feel like I'd be moving from a sweet spot a couple inches wide to one a couple feet wide

 

[primeVibe]

Looking at the TC on the floor, not even 2' high, my inner audiophile wanted it higher. So Duke lifted it higher where it might be used for stereo monitors. Interestingly, the change seemed to be only less bass and slightly more clarity, but I may have preferred it on the floor. Probably for stereo it would be preferred higher, but who knows? Duke, ya there?

Ryan Thorell and I were spaced about 10' immediately IFO of TC. Duke picked it up and turned it 90-degrees (can't remember which guitar for sure, maybe the flat top). Strangely, it was not like every other monitor you'd ever heard where you immediately feel like someone turned off the lights, so to speak. The sound was different, but not necessarily better or worse. Pretty cool, if not outright unbelievable, that persons in the audience seated so close but 90-degrees off axis could get such pleasant sound. I'm pretty sure relatively modest changes in spacing to the rear boundary wall can be used for some nuanced tone shaping.

At the TB member's home today, we damped the rear tweeter several times with a pillow. Under no circumstances did either of us prefer it damped, but rather we always preferred it open and functioning.

 

[DukeLeJeune]

Thanks, Prime!

I don't know about low bass cutoff for home audio because I employ a custom mode-flattening distributed sub array designed by Duke.

We both contributed to the design, and the concept traces back to Earl Geddes.

Lastly, we briefly heard my Bill Lawrence Telecaster through the AF/TC. I think Duke turned off the tweeter but he can chime in here.

Actually I had engaged the "tweeter rolloff" switch; the tweeter was still on, but rolling off gently north of 3.5 kHz or so.

Looking at the TC on the floor, not even 2' high, my inner audiophile wanted it higher. So Duke lifted it higher where it might be used for stereo monitors. Interestingly, the change seemed to be only less bass and slightly more clarity, but I may have preferred it on the floor. Probably for stereo it would be preferred higher, but who knows? Duke, ya there?

For home stereo use, it's a juggling act to get the optimum balance of imaging and boundary reinforcement in the bass region in a configuration that doesn't intrude on the room too much. Remember that you can plug one port if you're getting too much boundary reinforcement; that will drop the tuning frequency from 50 Hz to about 38Hz, raising the frequency where the low-end rolloff starts but making it more gentle, which often synergizes better with low end gain in a small room if the speakers are close to the wall(s).

At the TB member's home today, we damped the rear tweeter several times with a pillow. Under no circumstances did either of us prefer it damped, but rather we always preferred it open and functioning.

That low-level rear-firing tweeter, complementing a front-firing rectangular constant-directivity horn, has now found its way into my latest home audio speaker as well as into some custom studio monitors I'm working on. But it started out in a bass guitar cab. Derek Kiernan, who contacted me long ago about doing a cab for acoustic guitar and thus sparked development of the "acoustic friendly" version, has the very first one.

 

[loopee]

I'm getting excited......Duke says he'll start building my ThunderTots on Tuesday.....Yeah

 

[JxBass]

Pretty cool, if not outright unbelievable, that persons in the audience seated so close but 90-degrees off axis could get such pleasant sound. I'm pretty sure relatively modest changes in spacing to the rear boundary wall can be used for some nuanced tone shaping.

I really enjoy, almost prefer, listening to my TC off-axis when playing solo; a very full spectrum sound that has a nice ambiance to it, more so than when it's coming right atcha. Rear port wall positioning may have something to do with it as well.

Or maybe it's because my ears are unbalanced

 

[primeVibe]

I really enjoy, almost prefer, listening to my TC off-axis when playing solo; a very full spectrum sound that has a nice ambiance to it, more so than when it's coming right atcha. Rear port wall positioning may have something to do with it as well.

Or maybe it's because my ears are unbalanced

Exactly my point. My music interest started with a tube table top radio (AM only IIRC), then a tube portable TT w/ detachable speakers around the same time my dear parents bought my first guitar, then personal synthesizer studies with Patrick Gleeson (taught Herbie Hancock...I studied at Different Fur studio in SF where Pat and John Viera recorded Headhunters), worked at the Record Plant, etc, etc.

So I'm intimately familiar with live music and the finest systems reproducing it. I enjoy almost all types of music from classical to a sprinkling of heavy metal done right (a particular Ozzie Osbourne album comes to mind).

I know of no other Pro Sound or music instrument speaker providing TCs pleasant listening experience off axis. As previously mentioned, such speakers (except for AF/TC) sound like you turned the lights off when listening 90 degrees off axis: comb filtered, wooly, wavy, fuzzy, like cotton stuffed in your ears, etc.

The sound was even great while I sat behind AF/TC, so good that it took me a moment to realize I was sitting behind it! I double dare you to try that with another music/pro sound speaker!

 

[primeVibe]

I suspect that he engaged the rolloff filter, not turning off the tweeter. I've run guitars through the AF/TC with Bill Lawrence's new microcoils through low capacitance cables and gotten outstanding results.

I'm also strongly considering getting another AF/TC to use as a stereo setup as I like programmed music through it more than through my KRK studio monitors. We'll see what space and money I have when I move into a new apartment in a month or so. I feel like I'd be moving from a sweet spot a couple inches wide to one a couple feet wide

At age 57 it's fun to still have new and enlightening listening experiences. Over the years I've heard electrostatic speakers many times. A friend's ancient Acoustat 3 panels sounded very good. Another acquaintance about 20 years ago had a pair of huge Sound Labs with electrostatic sub woofers, but it sounded pretty bad, likely needing a lot of setup help.

Duke's respect for stats rubbed off on me. They sounded excellent at Duke's place, and even better at one CES setup by the late Bob Crump, co-designer of the Blowtorch preamp with John Curl (legendary high-end audio names). Ray Kimber's 4-ch system with two huge Sound Lab stats in each corner playing proprietary "Iso-Mic" Kimber recordings is a high lite of my listening experience (that system will never again be exhibited, about $330k value).

As hard as audiophiles will resist this statement, there is a lot of the mid-range performance of the best stats in Duke's current technology including and especially the AF/TC. I used to think this mid-range characteristic of the stats (for which they are legendary) was from the light weight of the diaphragm, resulting in extreme speed.

Duke's 12" woofer cones are obviously many multiples heavier than a stat panel, yet Duke's system provides a very close replica of the stat's mid-range performance. So I now presume low-weight diaphragms are not a prerequisite to achieve stat-like mid-range performance. Rather, the mid-range performance seems related to dynamic power and a particular, linear radiation pattern (obviously a stat employs a sum total one diaphragm and has no Xo splitting the signal, with all it's phase/radiation pattern artifacts, etc).

In the bass range TC comprises a juggling act including sensitivity, power handling, cabinet size/weight, and bass cutoff rate/frequency (users may fine tune these parameters by plugging one or both ports). Duke's further unique expertise was to translate decades of high-end audio fanaticism to the mid-range/treble performance and Xo range between the two drivers.

I apologize if all this was covered earlier. Persons familiar with Duke's high-end audio speakers will not be too surprised at TC's unique excellence in the music/pro sound field. I estimate he spent a good year considering the bass parameters mentioned above, then a good year longer achieving his mid-range goals, which were obviously much higher than any prior music-pro sound standards.

 

[thudfromafar]

At age 57 it's fun to still have new and enlightening listening experiences. Over the years I've heard electrostatic speakers many times. A friend's ancient Acoustat 3 panels sounded very good. Another acquaintance about 20 years ago had a pair of huge Sound Labs with electrostatic sub woofers, but it sounded pretty bad, likely needing a lot of setup help.

Duke's respect for stats rubbed off on me. They sounded excellent at Duke's place, and even better at one CES setup by the late Bob Crump, co-designer of the Blowtorch preamp with John Curl (legendary high-end audio names). Ray Kimber's 4-ch system with two huge Sound Lab stats in each corner playing proprietary "Iso-Mic" Kimber recordings is a high lite of my listening experience (that system will never again be exhibited, about $330k value).

As hard as audiophiles will resist this statement, there is a lot of the mid-range performance of the best stats in Duke's current technology including and especially the AF/TC. I used to think this mid-range characteristic of the stats (for which they are legendary) was from the light weight of the diaphragm, resulting in extreme speed.

Duke's 12" woofer cones are obviously many multiples heavier than a stat panel, yet Duke's system provides a very close replica of the stat's mid-range performance. So I now presume low-weight diaphragms are not a prerequisite to achieve stat-like mid-range performance. Rather, the mid-range performance seems related to dynamic power and a particular, linear radiation pattern (obviously a stat employs a sum total one diaphragm and has no Xo splitting the signal, with all it's phase/radiation pattern artifacts, etc).

In the bass range TC comprises a juggling act including sensitivity, power handling, cabinet size/weight, and bass cutoff rate/frequency (users may fine tune these parameters by plugging one or both ports). Duke's further unique expertise was to translate decades of high-end audio fanaticism to the mid-range/treble performance and Xo range between the two drivers.

I apologize if all this was covered earlier. Persons familiar with Duke's high-end audio speakers will not be too surprised at TC's unique excellence in the music/pro sound field. I estimate he spent a good year considering the bass parameters mentioned above, then a good year longer achieving his mid-range goals, which were obviously much higher than any prior music-pro sound standards.

and I get mine wednesday

pretty happy to be a part of all this