[Kevin Haskins]

Here is the CAD work on the tower speaker.    Still has some work to go but you can get the general idea from the PDF.


The bottom is a powered sub, with a pair of 7" drivers optimized for bass.   It should be good in-room to 25Hz with about 110dB from 25Hz & up (each).     That provides plenty of headroom AND bandwidth.

The design is modular, with the new monitor stacking on top of the powered bass module.    The bass module will also have the option of powering the monitor.   I'm using Hypex Class D amplification on both and since I have the power supply in place, I figured I'd take advantage of it.     

This is a semi-active design in that the crossover between the tweeter and midbass is still passive.   If you choose to use the active tower, you can still run the top through a typical amplifier, or choose to run line-level outputs to the bass module and run the entire speaker from the included high-quality Class-D solution.     The advantage would be that I can more carefully control the integration between the monitor and the bass module when I have active circuits at my disposal, allowing me to run subsonic filters on the top and have more control over shaping the response compared to using passive circuits.   

Of course this is all vaporware at this point.   Implimentation will depend upon how everything measures. 

www.diycable.com/main/pdf/tower.pdf

Kevin Haskins
Exodus Audio

[Kevin Haskins]

Looks interesting, what's your target price range?

How much will you pay Marbles?   

Really, I don't have a target.   I'm going to develop the product and let the price fall where it may.    Right now that would be in the $3K-$4K a pair range considering both the monitors + the powered sub portion.    It's highly speculative at this point though because I don't even have a cost estimate on most of the parts.

[Carl V]

are these bass drivers the same driver's used in the MT module?
--the newly designed midwoofer, 'pull out all the stops desgin'.

Are your present DIY  XBL midwoofers  capable of being used
in such a manner, i.e., in a lower 'bass bin' with a plate amp?
At VSAC you had such a PE enclosure. under your MT monitor.

[TerryO]

are these bass drivers the same driver's used in the MT module?
--the newly designed midwoofer, 'pull out all the stops desgin'.

Are your present DIY  XBL midwoofers  capable of being used
in such a manner, i.e., in a lower 'bass bin' with a plate amp?
At VSAC you had such a PE enclosure. under your MT monitor.

I'm not Kevin, but the VSAC speaker was a hi-efficiency design that ended up with a problem that couldn't be rectified in time for actual use. BTW, the speakers in the Bottlehead/Tape Project room used the Exodus Audio XBL2 woofers (4 per channel) and they sounded great.

I believe that Kevin has plans for a new XBL2 woofer that would be used in the Bass Module and perhaps elsewhere, but the design details are still being formulated, as you can tell from Kevin's first post.

As an aside, I'm using my Keplers and lovin' it!

Best Regards,
TerryO

[Carl V]

are these bass drivers the same driver's used in the MT module?
--the newly designed midwoofer, 'pull out all the stops desgin'.

Are your present DIY  XBL midwoofers  capable of being used
in such a manner, i.e., in a lower 'bass bin' with a plate amp?
At VSAC you had such a PE enclosure. under your MT monitor.

I'm not Kevin, but the VSAC speaker was a hi-efficiency design that ended up with a problem that couldn't be rectified in time for actual use. BTW, the speakers in the Bottlehead/Tape Project room used the Exodus Audio XBL2 woofers (4 per channel) and they sounded great.

Uh yeah I forgot about that...and they did indeed sound good.

I believe that Kevin has plans for a new XBL2 woofer that would be used in the Bass Module and perhaps elsewhere, but the design details are still being formulated, as you can tell from Kevin's first post.

I was mulling in my mind the possiblity of using two of his XBL2 Midwoofers the ones in your
Keplers in a bass Bin...using a Plate-amp with PEQ bass boost.

As an aside, I'm using my Keplers and lovin' it!

Yes, that Kepler was a very nice sounding Monitor.  Tone & timbre were good
as were thier dynamics.  You haven't tortured Kevin with that Flamenco FIM CD have you?
Best Regards,
TerryO

[TerryO]

are these bass drivers the same driver's used in the MT module?
--the newly designed midwoofer, 'pull out all the stops desgin'.

Are your present DIY  XBL midwoofers  capable of being used
in such a manner, i.e., in a lower 'bass bin' with a plate amp?
At VSAC you had such a PE enclosure. under your MT monitor.

I'm not Kevin, but the VSAC speaker was a hi-efficiency design that ended up with a problem that couldn't be rectified in time for actual use. BTW, the speakers in the Bottlehead/Tape Project room used the Exodus Audio XBL2 woofers (4 per channel) and they sounded great.

Uh yeah I forgot about that...and they did indeed sound good.

I believe that Kevin has plans for a new XBL2 woofer that would be used in the Bass Module and perhaps elsewhere, but the design details are still being formulated, as you can tell from Kevin's first post.

I was mulling in my mind the possiblity of using two of his XBL2 Midwoofers the ones in your
Keplers in a bass Bin...using a Plate-amp with PEQ bass boost.

As an aside, I'm using my Keplers and lovin' it!

Yes, that Kepler was a very nice sounding Monitor.  Tone & timbre were good
as were thier dynamics.  You haven't tortured Kevin with that Flamenco FIM CD have you?
Best Regards,
TerryO

The Flamenco CD did get a lot more play than most people would want in a relatively short time-span. Interestingly, it was that very evening that I first noticed that Kevin would develop a facial "twitch" whenever someone would stamp their foot on the floor .

I bought the CD for my own private reference collection, as it will tell you in short order if the cabinet tuning and stuffing are off. Those sharp, percussive sounds are a real test for any speaker, and perhaps more importantly, it's readily apparent to most listeners once they pay attention to that particular sound.

Best Regards,
TerryO

[kfr01]

Really looking forward to hearing more about these.  I've never regretted buying/building your 2641 towers for a minute.

[Kevin Haskins]

Yes, that Kepler was a very nice sounding Monitor.  Tone & timbre were good
as were thier dynamics.  You haven't tortured Kevin with that Flamenco FIM CD have you?

Ha!   Terry has tortured me with a number of recordings.   I have that sample recording from the speaker contest in my car CD player and my kids give me a anguished look whenever I turn it on.     

I'm using the same amplifier in the bass modules as I used at VSAC 2008 with the option of powering the top monitor from them.    The user can power the top with their own amplifier ala the standard passive crossover or they can opt to use the Hypex Class D solution I'm packaging in the bass module.    I figure I keep everybody happy that way.   The people who want to swap and match their own amplifier solutions can do so and those who want a complete cost-effective active design have it available with the bass module.   

It is a very green design too.   High efficiency and I'm hoping to pair it up with a Transporter driving a pair of speakers as a complete system.     That way I don't have to lug a bunch of equipment around at shows. 

[Kevin Haskins]

are these bass drivers the same driver's used in the MT module?
--the newly designed midwoofer, 'pull out all the stops desgin'.

Are your present DIY  XBL midwoofers  capable of being used
in such a manner, i.e., in a lower 'bass bin' with a plate amp?
At VSAC you had such a PE enclosure. under your MT monitor.

They are not the same driver.   This is a different midwoofer than I'm currently using in the Kepler kit.   This also is not a plate amp solution.   I'm custom designing a signal processing board and using the Hypex amplifiers I've been building for years in the application.   I know they sound great and they have a proven track record in terms of reliability.     

Plate amps suck.   

[dyohn]

Plate amps suck...

... electricity right out of the wall.    Why not design a plate amp using a Hypex module?  Sell it as a high-end DIY subwoofer solution... include a woofer widget... or maybe not.

[Kevin Haskins]

Plate amps suck...

... electricity right out of the wall.    Why not design a plate amp using a Hypex module?  Sell it as a high-end DIY subwoofer solution... include a woofer widget... or maybe not.

David,

I was thinking of that "Rainman" movie with Dustin Hoffman and Tom Cruise.    Dustin Hoffman is one of my favorite actors and that was one of his best roles.    Tom told him "K-Mart sucks".      I bet that one line in a movie cost K-Mart millions of dollars in lost revenue.   

Plate amps have their place but I have irrational expectations for the finished Exodus speakers.    They represent my best-effort and I'm designing everything from scratch.    This just isn't a product where I want to cut corners and plate amps typically use the cheapest parts that the Chinese can source.   Price is the #1 determining factor with plate amps.   The caps in particular are often lucky to last five years before failing.     

Everything I'm using in these finished speakers is top-notch.   I'm not dogmatic about magic parts but I am about parts quality, Q/C and overall design quality.   In other words I'll pay for high quality Panasonic built caps, but nothing blessed by a virgin.   Opamps are high quality but I'm not going to piss money down the drain using a $100 part where a $1 one will work just as well.    Both you and I know that there are many times when the $1 part outperforms the $100 part.    Each choice will be made based upon what I feel is best for the application and I don't really care about the cost nor the audiophile dogma surrounding it.   

In terms of Hypex plate amps.   They already sell a product.   It cost about twice as much as your typical plate amp and wouldn't sell.         Ok... it would sell but not in high enough quantity to monkey around with.   


           

 

[TerryO]

Ha!   Terry has tortured me with a number of recordings.   I have that sample recording from the speaker contest in my car CD player and my kids give me a anguished look whenever I turn it on.     

Kevin,
I don't know if I'll have my latest recording done in time for you to get it as your Christmas present. This one will feature me singing my personal interpretation of favorite German Christmas Carols, with Bagpipes, Castanets and Flugle-horn backup. I don't believe that anyone has done this before, but it will astonish the listener.
BTW: In the softer passages you'll hear the bellowing of a herd of stampeding Bull Elephants. I didn't originally think it would work...but it does!

I'm using the same amplifier in the bass modules as I used at VSAC 2008 with the option of powering the top monitor from them.    The user can power the top with their own amplifier ala the standard passive crossover or they can opt to use the Hypex Class D solution I'm packaging in the bass module.    I figure I keep everybody happy that way.   The people who want to swap and match their own amplifier solutions can do so and those who want a complete cost-effective active design have it available with the bass module.   

It is a very green design too.   High efficiency and I'm hoping to pair it up with a Transporter driving a pair of speakers as a complete system.     That way I don't have to lug a bunch of equipment around at shows. 

That looks like the ideal portable setup! The added bonus is that it would also sound great.

Best Regards,
TerryO

[doorman]

How much for just the castanets??
Don

[dyohn]

Bwa ha!  A Rainman reference, how silly of me to miss that.  I agree, it is one of Hoffman's best performances and one of my favorite films.

Caps!  Doh!  Thank you.  I use an old plate amp I bought from North Creek about 8 years ago on my 2-channel sub and it's been giving me strange issues like suddenly developing a ground loop hum where before there was none, random power fades, etc.  Caps!  Time to pull that bad boy, break out the soldering iron and replace them and see if that's the problem.  Thanks!

I was actually half-kidding about the Hypex plate amp, but it's interesting to know that they have one. And yes, more often than some might expect the $1 part at least equals the $100 part.  And often the $1000 one too. 

I think your dual-chassis all-active design will be a killer system... a Meridian-killer system.    I look forward to what it'll do when it's here.  I'm working my Stereophile contacts for ya.  Fall '09 time frame? 

[TerryO]

How much for just the castanets??
Don

Don,
The Castanets are what you're paying for, all the rest is thrown in as a free bonus.
 aa

Best Regards,
TerryO (aka "Mario Lanza")

[Carl V]

Plate amps suck...

[/quote]
In terms of Hypex plate amps.   They already sell a product.   It cost about twice as much as your typical plate amp and wouldn't sell.         Ok... it would sell but not in high enough quantity to monkey around with.   

[/quote]

I've owned a few hypex plate amps in the past via Adire i.e.,200 & 500.  They seemed
pretty good.  LR-4 XO nice power....Taller than most maps.  I still have their big
boy ADA1200...wish now I had bought a few more or their lower powered versions.

2-12dB XO for 24db slopes, 3-PEQ, phase, gain......very nice actually. Were these
Asian, German or a Washington Combonation?

Back to the original inquiry?  Would 2 of the Kepler XBL2 Midwoofers work well as
a Bass Bin in say a 1ft3 PE enclosure or a DIY 1.5--2.0 ft3 enclosure?

[Kevin Haskins]

2-12dB XO for 24db slopes, 3-PEQ, phase, gain......very nice actually. Were these
Asian, German or a Washington Combonation?

Back to the original inquiry?  Would 2 of the Kepler XBL2 Midwoofers work well as
a Bass Bin in say a 1ft3 PE enclosure or a DIY 1.5--2.0 ft3 enclosure?

Wiggins plate amp was made in Lynnwood Washington.   I'm sure he had to source transformers from overseas and most components come from all over the globe but the PCB, plate and final assembly where done in-house.   It didn't fit in the stereotype of "Plate Amps Suck".     

The current EX-6.5 will work great in a 1.0 cubic foot PE box used at a bass cabinet.   I'd tune it to around 40Hz and you need a good 3" diameter flared port for a pair of those drivers.    You may be able to get by with smaller if you have moderate SPL needs.   The larger cabinet isn't really needed although you can push it up to about 1.5 cubic foot.

[Kevin Haskins]

How much for just the castanets??
Don

I'm not sure I catch your meaning.   Are you talking about the thingies on the bottom of the cabinet?   They are just a computer model at this point.    I'm probably going to revise the base so that it has a wider footprint for stability.    I don't have any plans to sell portions of the design to the DIY market.     They get built in the factory and we just wouldn't be set-up to deliver parts and pieces of the final product.   

[Kevin Haskins]

I think your dual-chassis all-active design will be a killer system... a Meridian-killer system.    I look forward to what it'll do when it's here.  I'm working my Stereophile contacts for ya.  Fall '09 time frame? 

Oh.... I'm not going to speculate right now.   There is lots of work yet to be done and I'm not going to rush it.    The drivers are pretty much finalized (one more revision on the midwoofer) but the cabinet stuff is nothing but computer models at this point and the crossover work hasn't started.    I almost have a first prototype PCB done on the signal processing but I'll need the drivers and the prototype cabinets to do the final revision.    I'd say Fall of next year is a realistic time-frame because once I finalize everything it is still 90 days to get a production run done and into stock. 

[Kevin Haskins]

I've been working on this all day.   I have the bass module pretty much dialed-in.   It will require some adjustments once I get prototypes but they should be small ones that are more about voicing it rather than drastic changes.

The 3dB down point in free-space is @ 31Hz and it's about 11dB down @ 20Hz.   I may need to adjust this because that kind of low frequency curve will give us an in-room peak @ 30-50Hz.    It is not unusual to see that in commercial speaker designs but I'll play with it in a couple rooms before finalizing the bottom-end response.   The great thing with the active set-up is I can tailor it in ways that just are not possible with a passive filter.   



The system has a crossover @ 60Hz between the monitor and bass modules when driven by the active crossover.   It is a 2nd order acoustic so it allows for good overlap and sharing of the bass load among three 7" drivers.   I actually like some overlap when the bass unit has good clean response and the upper midwoofer has the capability of playing lower.   It shares the load of producing the midbass among all three drivers and you don't see large off-axis nulls due to the wavelength this low.    Each of these drivers is equal to about a typical 8" Scan-Speak driver (or 10" if you are using typical drivers) so you have plenty of output capability.    I'm estimating I'll have 110dB from 25Hz & up from each speaker.    The tuning frequency of the lower cabinet is around 26Hz so much of the contribution on the bottom is from the port, keeping distortion low within the speaker's bandwidth.   Also the active design has allowed me to provide great protection under port tuning for all the drivers.   You won't be able to drive it into significant distortion without the amp clipping.   You are at stupid output levels at that point.   

This is a true full-range speaker!   The in-room response will be flat to 20Hz and it will be capable of clean output throughout it's bandwidth.    It should achieve that with a very reasonable footprint of 10" Wide, 17" deep & 44" tall.