The new Exodus Audio KIT61

Kevin P · « **on:** 28 Mar 2005, 10:06 pm »

The new Exodus Audio KIT61 using the Adire Extremis 6.8 & Usher 9550-C. The low frequency response of this monitor speaker 17"h x 10"w x 12.5"d enclosure embarrasses most full range tower speakers. Expect low frequency performance well into the 20s in-room and 30-35 anechoic.

The Extremis uses Adire's new XBL^2 motor technology allowing unusally low distortion & power compression along with extended bandwidth. The Usher 9550-C is one of the best bang/$ tweeters on the market. It performs with the very best tweeters at any price for a $70 retail price. Combine the two with a good crossover design and you have one of the most remarkable monitor speakers in the world.

Price? The kit is $399/pr including everything but the wood. The design accomidates the Parts Express 0.75ft^3 assembled enclosures ($85 each) making this one of the easiest to assemble kits on the market.

Availability..... soon... very soon.

For some scale here is a picture with CD case on top.

A simple on-axis response measured from 1M with Liberty Praxis, Autopod, M-Audio Transit & calibrated mic.

klh · « **Reply #1 on:** 28 Mar 2005, 11:57 pm »

I was just reading about this elsewhere on the web. Re: the KIT261 and the LCR, will they be voice compatable (and if not will a compatable center channel be designed)? Also, will other surround type speakers be designed (and if so, will they be compatable with the LCR, KIT61 and/or KIT261)? Sorry, one more questions... do you know how efficient the previously mentioned speakers are? Thanks.

Kevin P · « **Reply #2 on:** 29 Mar 2005, 02:22 am »

Sure.... really any of them could be used as a center channel speaker. They are all shielded and all have a wide enough bandwidth to do the job.

Laying them on their side will effect the dispersion though because the off-axis vertical response differs from horizontal off-axis response. You would need to position them sitting up for the best dispersion characteristics.

The LCR, as its name suggest, is a left/center/right speaker. It is designed to lie on its side and sit upright with an engineered power response that compliments that kind of arrangement. It uses a pair of Extremis 6.8s to cover the low end, a single CS-125 as a midrange and a single Usher 9950 as the tweeter. This is what I consider an "extreme" solution in that it has over 111db of headroom per speaker at a normal 8-10ft listening position. Having three across the front stage give you incredible output and linearity and really wide bandwidth..... true full range but having a beefy center channel is great. Once you hear this kind of set-up it is hard to go back to an anemic little underpowered center channel and the CS-125 has an absolutely gorgeous midrange. The downside of course is the size & expense. The LCR is not going to be an inexpensive speaker because you have about $360 in drivers alone per speaker. If size and expense is not an issue (I'm going to stick mine behind my projector screen) this will be the ultimate front stage speaker.

The MMT is a tower speaker with two Extremis 6.8s & the Usher tweeter. It is not really designed as a center channel but would match up well with a single KIT61 used in that role.

In smaller sizes we have the KIT41 and some variations of it soon to be released. There is an MTM (which doesn't give the best horizontal dispersion laid on it's side), which you traditionally see used as a center channel, which could be combined with the KIT41 for surrounds. I'm also designing a MT with the CS-125 & the Usher for a computer monitor so there will be options with the CS-125 also.

The KIT61 is about 86db/1W/1M in terms of efficiency. This is a somewhat vague measurement though because it says nothing about how the system acts under power. One of the benefits of the XBL^2 motor design is that it has much less power compression. This means that under power it plays louder and more dynamic than a normal driver. This makes the Adire drivers sound much more efficient than their 1W/1M specification would suggest.

klh · « **Reply #3 on:** 30 Mar 2005, 07:22 pm »

Thanks for the response. The LCR sounds like it'll be a great speaker. Will the MTM or any other surrounds be designed so they can be placed on or near a wall? Do you know if dipole/bipole speakers are in the works?

Kevin P · « **Reply #4 on:** 31 Mar 2005, 01:04 am »

We are working on some surrounds with the WR-125 & Usher that are designed to use on the small wall-mount brackets or close to a room boundry. The MTMs could be used that way but it would make sense to port them out the front rather than rear.

We don't have a dipole under development. We are aiming to get all the current designs to market first and then we will work on additional projects. I personally wouldn't mind doing a dipole with the Extremis & the WR-125 but there isn't any kind of time frame at the moment.

klh · « **Reply #5 on:** 31 Mar 2005, 01:35 am »

OK. Thanks for for the clarification

kfr01 · « **Reply #6 on:** 20 Apr 2005, 04:57 am »

Alright, here's my attempt at building a speaker the wife will enjoy with a very cheap and easy finish.

I used this spray: http://www.cornerhardware.com/item_266164/Rust-Oleum/Rust-Oleum/American-Accents-Bleached-Stone-Textured-Spray-Fin/item.html after sanding and priming multiple times. Then put a clear protective coat on top of the stone spray. They turned out pretty good by my non-artsy standards. The roundover router bit on the front baffle helped improve the "not an MDF box" look quite a bit. Neither the countersink diameter nor the countersink depth for the Extremis cutout was quite right. Would I do this again I would "get it right" on a test baffle first, before charging forward. The tweeter fit snug and is flush.

I used dual terminals on the back and plan to mount a crossover box to the stands that have yet to be built.

The Exodus kit comes well packaged and everything is in top-notch form.

The sound --- wow! I am absolutely shocked by how complete and full the sound is coming from a rather simple 2-way bookshelf. This Kit is a fantastic value, easy to build, and sounds great. My favorite types of music are jazz and classical. The kit REALLY excels at these types of music. Other bookshelves that -require- a subwoofer to augment the bass always seem to get bloaty because of the requisite high crossover frequency. "Oh, listen, there's the sub kicking in." With the Extremis the bass is just there. Nice and accurate and dead-on in the image. I also tested them out with some r&b/rap and rock. They played really well with the rock. The kick drums kicked, the bass guitar was defined. Very good. The r&b/rap was also good... but the clean bass might actually take some getting used to for this sort of music. Some bass heavy dance-type r&b and I think almost all rap tracks are meant to have boomy, dirty and too-hot bass, I think. The bass this kit puts out is neither boomy nor dirty and is excellently balanced. Rap/boom fans might want to consider a sub to augment the Kit61. For stereo listening of other kinds of music I can't say enough about these speakers... Bravo! (Now I'm itching to move these to the rears and try a pair of LCR's).

If I was to make one modification, I would probably sandwich some MDF behind the tweeter or seal the tweeter off from the Extremis chamber. I don't think it affects the sound any, but touching the Usher tweeter's front plate reveals a hint of vibration when the Extremis is moving. Also, friendly tip - be sure to test tweeter fit WITH the speaker clips and speaker wire attached. I made the unfortunate mistake of testing tweeter fit only with the driver itself. When I finally got the speaker all finished and ready to mount the tweeter, jumping out of my pants w/ excitement, I learned that the little notches were too small. So, then I had to route the notches a little larger. In the process I hit some of my finish and had to touch some of that up with a few short sprays of left over paint. Anyway, test the notches.

Here are some pics:

ooheadsoo · « **Reply #7 on:** 20 Apr 2005, 05:05 am »

Very nice job! I hope to be able to hear these speakers one day.

Kevin, do you think you could post the reverse null response of the speakers when you have a chance?

Kevin P · « **Reply #8 on:** 20 Apr 2005, 04:11 pm »

Quote from: ooheadsoo

Very nice job! I hope to be able to hear these speakers one day.

Kevin, do you think you could post the reverse null response of the speakers when you have a chance?

Are you just looking for the crossover point? My prototype set of speakers are over at the Adire showroom at the moment so I don't have a set of speakers to pull apart, change the polarity and measure.

The reverse null gives about a 15-20db narrow dip at around 3.1K. The crossover is about a 4th order acoustical on the tweeter and 6th order acoustic on the woofer. Those are approximations because we don't use cookie cutter crossover designs that are a simple 1st, 2nd, 3rd, 4th order etc...

Kramer · « **Reply #9 on:** 20 Apr 2005, 04:12 pm »

Quote from: kfr01

Alright, here's my attempt at building a speaker the wife will enjoy with a very cheap and easy finish.

Why didnt you offset the tweeter?

Kevin P · « **Reply #10 on:** 20 Apr 2005, 04:41 pm »

Quote from: kfr01

Alright, here's my attempt at building a speaker the wife will enjoy with a very cheap and easy finish.

I used this spray: http://www.cornerhardware.com/item_266164/Rust-Oleum/Rust-Oleum/American-Accents-Bleached-Stone-Textured-Spray-Fin/item.html after sanding and priming multiple times. Then put a clear protective coat on top of the stone spray. They turned out pretty good by my non-artsy standards. The roundover router bit on the front baffle helped improve the "not an MDF box" look q ...

Nice work! I've updated the drawings to point out the amount of countersink for both drivers. It's always best to have the actual drivers your trying to mount because there always seems to be something that you overlook when just going from raw plans.

Kevin P · « **Reply #11 on:** 20 Apr 2005, 04:46 pm »

Quote from: Kramer

Quote from: kfr01
Alright, here's my attempt at building a speaker the wife will enjoy with a very cheap and easy finish.

Why didnt you offset the tweeter?

The picture I posted was of a prototype. The final version of the KIT61 has it centered on the baffle. There is a theoretical advantage to having the tweeter at odd distances from every baffle edge. In practice it wasn't audbile and keeping them centered up simplified the building plans.

Kevin P · « **Reply #12 on:** 20 Apr 2005, 07:34 pm »

I just updated the documentation on the KIT61 for those who have downloaded the assembly guide.

Changes:

#1. New Brace shown in drawings. This eases crossover mounting as you have room to fasten it to the floor of the enclosure with this new brace design.

#2. Crossover schematics simplified.

#3. More notes on countersinking dimensions for the drivers.

#4. We cut the ports to length before shipping them so we removed directions for cutting the port to the correct length.

There is also some more measurements on the web page. I scooped these from Dan Wiggins who measured a impedance plot also.

Exodus Audio KIT61 Page

kfr01 · « **Reply #13 on:** 20 Apr 2005, 08:39 pm »

Good call on the new brace design. The old one would have made things a bit cramped had I wanted to mount the xo inside the speaker.

Stands are drying w/ glue as I type this. They were made out of 3 very thick MDF stair peices. They aren't pretty. My wife informed me that the stands as I currently have them built - "will have to change." Whatever. <$20 for two quick and heavy stands is worth it... I'm dying to hear the speakers on proper stands!! (Rather than a desk or coffee table).

That said, anyone know of any cheap + easy + stylish stand designs that would suit the Kit61?

ooheadsoo · « **Reply #14 on:** 20 Apr 2005, 10:00 pm »

Thanks, Kevin, I just wanted to see how deep the null is/the shape.

Kevin P · « **Reply #15 on:** 20 Apr 2005, 11:16 pm »

I'm building up a pair out of granite next month. I'll measure it for you then and post it.

DanWiggins · « **Reply #16 on:** 21 Apr 2005, 04:37 am »

Quote from: ooheadsoo

Thanks, Kevin, I just wanted to see how deep the null is/the shape.

It's not as deep as many would think would be ideal; however that's a side effect of the crossover design. The phase is actually linear from ~300 Hz to 5 kHz, well past the crossover on either side. As a result there's a bit of overlap in phase of the two drivers, and the null is "only" 15 dB down or so. Of course, it is a full effective 6th order crossover, so it still rolls off really hard (keeping off-axis lobes to a minimum).

If properly done, you can do linear phase to an octave beyond the XO - it's not just limited to first order networks!

Dan Wiggins
Adire Audio

kfr01 · « **Reply #17 on:** 21 Apr 2005, 05:27 am »

Hey guys, thought I'd post one last picture of the pair on proper stands. I still need to sand / prime / paint my stands, but they'll probably remain unfinished while I enjoy my speakers for a couple weeks. The sound continues to impress. I'll be in this spot every evening for some time. Next on the todo list: cord management and new entertainment center.

kfr01 · « **Reply #18 on:** 25 Apr 2005, 11:45 pm »

I couldn't stand the raw mdf, so I finished my stands. These stands cost $20 each and went together very fast. I'm quite pleased with my idea to use thick MDF stairs.

Not bad, right?