SCC300 on the bottom

David Ellis · « **on:** 26 Jan 2004, 12:58 am »

In this forum I would like to address the questions and concerns about this project. I will also offer that... it ain't finished yet. It started almost 18 months ago, but has taken a back-seat to other priorities.

I am fairly confident the driver compliment will be the SCC300, W18EX001 with some mods, and the OW1F.

The W18EX with some mods is necessary because the SCC300 sensitivity is a very solid 90db. The mods are simple neo magnets which add about 1.6db to the W18EX. The result is a more senstive driver that will mate with the SCC300 easily. Adding the magnets also makes the W18EX faster, and drops the Qes... Qts, but these things are a small issue IMO.

Upon tentative completion, I'll again test the OW1 and OW1F for sound quality desparity. At this time, nobody can discern any audible difference between these drivers. There is a single and very good explanation for this. Oskar uses a very thin ferrofluid placed carefully around the voice coil gap. The use of this very thin fluid is possible because Oskar's tolerances are very tight. With tight tolerances the thin fluid works just fine. The use of thinner fluid impeeds voice coil movement very little. Thus far the impact is NOT audible. The only impact of using the OW1F appears to be greater power handling.

Since the power handling of the W18 woofer is greatly enhanced, the tweeter arena will be the area of power handling weakness for this 3-way. Using the OW1F will easily fix weakness. Using the OW1F appears to be a win-win situation.

Dennis found a pleasing crossover, but the impedance dropped to 4 ohms. When I complete another pair of cabinets, I'll work on the crossover with the sole focus of maintining higher impedance. This should be viable due to a woofer impedance of 6 ohms. For the moment, I asked Dennis not to spend more time on this crossover. This is because I am capable and really enjoy this work. If I hit snags, I'll obviously call the wise old sage for advice.

I am encouraged by this speaker for the following reasons.

1. The bass is amazing.

2. The midrange of the W18 is better too. This follows decreased IMD and decreased thermal compression.

3. The power handling, sensitivty and SPL potential are whopping huge!

I am disouraged by this speaker for the following reason.

1. The size/mass of the cabinet is whopping huge! This contributes to a speaker that is NOT wife friendly - even when constructed well. It is slow to build and very heavy. Shipping will only be possible via pallet - expensive.

My goal with the 1801 was a loudspeaker with killer midrange/highs, and very decent bass to 40hz. It was intended to be a two-way speaker that I could enjoy for a lifetime. I believe this goal is accomplished.

My goal with this 3-way project is a world class loudspeaker in all aspects. I believe this will happen, but the cost/labor involved is significant. The kit will probably cost about $1200 (?), and I might sell the first completed speaker for $3k. After this, the cost will rise. They are extremely time consuming to build. I now understand why Avalon and Kharma charge $20k for their speakers. The cabinets take considerable time and effort.

Dave

Al Garay · « **Reply #1 on:** 26 Jan 2004, 03:39 pm »

What are the approximate dimensions?

Too bad that it does not provide an upgrade path for existing 1801s.

Al

David Ellis · « **Reply #2 on:** 26 Jan 2004, 04:31 pm »

These pictures should provide a general idea of the dimensions. These are the rough test-mule cabinets. They are 22" deep.

Given the 90db/watt sensitivity of the SCC300 woofer and low crossover point, there is no way the 86.5 db W18E will work.

Al Garay · « **Reply #3 on:** 14 Feb 2004, 06:50 am »

Hi David,

Is the tweeter sealed in the top compartment?

Would the OWII be a closer match in sensitivity, 90db?

This could really be a 3-way that Avalon Acoustics would be proud to have for about $15k.

Thanks,

Al

David Ellis · « **Reply #4 on:** 14 Feb 2004, 08:31 am »

Quote

Would the OWII be a closer match in sensitivity, 90db?

Good thought Al, but no.

The 6db acoustic rise from @150hz to 1200hz via the baffle step loading makes an 86-87db tweeter easily viable. This is because the tweeter becomes 92-93db after the baffle step. This is true with ALL loudspeakers.

The only change among various loudpspeakers is when the baffle step begins. Louspeakers with bigger baffles start & end their baffle step lower. Loudspeakers with smaller baffles start & end their baffle step higher. In all cases the impact is a 6db bump from low frequency to high frequency.

The tweeter might be an OW1F... time will tell.

Have you heard the bass from the Avalon speakers?

Quote

Is the tweeter sealed in the top compartment?

Yes and no. All Hiquphon tweeters are sealed via their integral chamber as provided by Oskar. I suppose this infers a "yes". Hence,there is no need to construct an additional lumber chamber. However since the spirit of your question pertains to some lumber enclosure behind the tweeter the answer is "no".

Al Garay · « **Reply #5 on:** 14 Feb 2004, 08:45 pm »

Nope. Unfortunately, I have not found anyone in WA with Avalon's. I would love to hear the Eidolon's with Ayre Acoustics gear. Gives me a good benchmark to compare my current setup (1801 with AKSA/BentAudio).

The closest I have come is a friend who built a clone of the Ascent's using the Eton 11.2 kit, which uses the same 11" woofer and possibly the same mid, Eton 5-880... though I'm not certain that the Ascent used the same one or was it an Accuton? Anyways, the bass was extended down to about 27Hz. Tight. Quick. Though, not much energy. Did not make my kids dance.

My 1801s with the single sealed SCC300 does make my kids (and picture frames) dance. I found out they like Dire Straits, Eagles, BTO, Santana along with their Disney music. I imagine the 3-way you are planning will also make them want to dance.

Al

David Ellis · « **Reply #6 on:** 14 Feb 2004, 10:55 pm »

Well,

When you have the time, I suggest auditioning the Avalon stuff. It is good , oh yes. The auditon will also provide a very good understanding of where the 1801 and SCC300 fall into the mix.

I don't feel proper commenting further.

If you and your wife have the urge to visit LasVegas, try to constrain the date to very early January. This is when CES happens. You will have the opportunity to audition EVERYTHING if you attend CES.

Dave

Figo · « **Reply #7 on:** 15 Feb 2004, 01:17 am »

do you think that the 3 way with the SCC300 will be better than the L26/W26 3way?

other way around?

also, how about price/cabinet size wise.

David Ellis · « **Reply #8 on:** 15 Feb 2004, 02:25 am »

Quote

do you think that the 3 way with the SCC300 will be better than the L26/W26 3way?

Yes.

Quote

also, how about price/cabinet size wise.

The kit cost(s) will be the retail cost of components. The completed speaker cost will encompass the time & materials involved. Since the 12" woofer requires considerably more cabinet it'll be more expensive in a completed speaker.

Shipping will be the big issue really. They 12" woofer cabinet is very big and very heavy. It will have to be shipped on a pallet and this isn't cheap for small business guys like me. The 10" woofer cabinet will be viable for shipping via FedEx ground or DHL. I need to inquire about DHL. While FedEx is pretty decent about delivering packages, their logistics and billing are a "pain in the neck". DHL might be easier.

I haven't completely decided on completed speaker cost yet. This will remain undecided until I finish the projects. There are a few more details concerning cost in my first post above.

stvnharr · « **Reply #9 on:** 15 Feb 2004, 08:05 am »

Shipping on a pallet may not be cheap, but it does insure that the product will arrive in good order. It is worth the cost. This has been confirmed by me, as well as by a long time audio dealer that I know.
There still seems to be no free lunch.

David Ellis · « **Reply #10 on:** 15 Feb 2004, 12:35 pm »

Yes, I have heard this too. Thanks for the input.

Dave

Figo · « **Reply #11 on:** 15 Feb 2004, 05:40 pm »

Quote from: David Ellis

The kit cost(s) will be the retail cost of components. The completed speaker cost will encompass the time & materials involved. Since the 12" woofer requires considerably more cabinet it'll be more expensive in a completed speaker.

Shipping will be the big issue really. They 12" woofer cabinet is very big and very heavy. It will have to be shipped on a pallet and this isn't cheap for small business guys like me. The 10" woofer cabinet will be viable for shipping via FedEx ground or DHL. I need to ...

excellent. So, are you replacing the L26/W26 idea with the SCC300 idea?

also, do you have a vague idea of when it will be finished?

David Ellis · « **Reply #12 on:** 15 Feb 2004, 05:48 pm »

Quote

excellent. So, are you replacing the L26/W26 idea with the SCC300 idea?

Nope, both projects will happen.

These speakers might seem very similar. Inded the kit cost will likely be very similar. Therefore the completed speaker might be similar in cost too - until considering the cabinet. The significantly bigger cabinet of the SCC300 speaker is much more difficult and the cost will be commensurately higher.

Dave

Al Garay · « **Reply #13 on:** 16 Feb 2004, 12:16 am »

Are you thinking rear-ported? What about sealed? I expect the sealed will be easier to position, closer to rear-wall.

How far from rear-wall do you expect these needing to be ... measure to the front baffle. Wondering if these will need to be 4' to 6' from rear wall, which would be a bigger WAF than the size. Also, we have a 9' foot entertainment center (along a 18 foot wall). And the 1801s are happy being 24" to 30" inches away from rear wall and close to the sides of the ET. It's not as ideal as having them 6' apart. It's all about comprimises and we are very happy how the family room looks. Now, trying to improve the sound with the added bulky furniture.

Thanks,

Al

David Ellis · « **Reply #14 on:** 16 Feb 2004, 12:55 am »

They will be sealed. I find this matches room lift much better than ported when the sealed f3 is below 40hz. All things are a compromise though.

I am learning there are very significant room variations. They dramatically effect the lift/response below 200hz (or so). My 1801s in Kevin Becker's home had a huge quantity of midbass/bass. It was a striking change when compared to placement in my room. The difference was/is construction. Kevin' has a 1/2 concrete wall in his basement listening room. I have a 10' sheetrock wall. The latter is much softer in the bass region. Because of room/construction issues I cannot make a pervasive statement about room placement and the desired bass response.

The sound balance in the midbass region will likely be darn similar to the 1801, so the result will be the same.

Dave

Al Garay · « **Reply #15 on:** 17 Mar 2004, 04:31 am »

Hi David,

Welcome back. In regards to this ultimate 3-way, how would you describe the difference between this design and the combination of the 1801b with a pair of sealed 3.0cf subs?

Thanks,

Al

David Ellis · « **Reply #16 on:** 17 Mar 2004, 12:48 pm »

Al,

Dennis tried using an electronic crossover between the midrange (W18) and the woofer (SCC300). He was easily able to move the crossover point, but NOT able to contour the slopes to fit the drivers. The result was a slightly erratic frequency response with the electronic crossover. When using passive components, it's possible to accomplish a custom slope contour for each driver while still accomodating the rest of whats possible via electronic crossover. The result is an acoustic filter that's measures and sounds perfectly flat. The result was a passive filter that looked better when plotted and sounded better to the ear.

Because almost NO drivers are perfect, an electronic crossover will never equal the sound quality of a well implemented passive crossover. This is simply because the passive crossover will be flatter.

There are other issues extant. One of them is room modes. They are tenacious below 300hz is darn near every room. The audible need for a flat crossover between a midrange and subwoofer decreases as the crossover frequency drops. An erratic frequency response becomes less important at lower frequencies. This is simply because low frequency room modes will swamp response imperfections.

Again, there are other issues present when discussing the difference between a monintor/sub versus 3-way setup. The entire disscussion is VERY long. I think the above comments are probably the most significant when addressing your concern because the drivers are the same.

Please let me know if further explanation is necessary.

randog · « **Reply #17 on:** 17 Mar 2004, 04:09 pm »

I would be interested in experimenting with this. I just purchased a pair of SCC300 drivers from Jeff and am having 3.0 cubic foot enclosures fabbed that will sit under the 1801's. I decided on front rather than down-firing.

First I'll try it the conventional way, but if that doesn't work as well as I'd like, perhaps I could integrate the new crossover into the setup

That would be an interesting experiment.

Dave, will the new crossover design be proprietary?

Randy

Al Garay · « **Reply #18 on:** 17 Mar 2004, 07:05 pm »

The Ellis 1801 drivers will not work with the 3-way. The tweeter is a variant of the OW1 called OW1F and the woofer is the W18EX001 which has greater sensitivity. It would have been nice to provide an upgrade path but it would have restricted the design too much esp. shooting for a world-class 3-way.

I won't mind saving my dollars to buy the additional drivers. And I would not mind trying the 4ohm crossover (hint: for Beta testing). That would be no different from the Avalon Eidolon which would be a good target.

By the way, Ellis' crossover designs are proprietary. And we do want to protect his interest to honor the services that he provides us.

Thanks,

Al

randog · « **Reply #19 on:** 17 Mar 2004, 07:17 pm »

Quote from: Al Garay

By the way, Ellis' crossover designs are proprietary. And we do want to protect his interest to honor the services that he provides us. ...

Of course, that's why I asked. And it's not like I'm not a customer, which is also why I asked. The 3rd reason I asked is because Dennis Murphy regularly gives away his own crossover recipes, so it wasn't clear to me if the crossover design was being contracted by Dave or not (as proprietary)... which, of course, is why - I - asked.