Cynosure Project

[GBBinaural]

Let me start of by saying that I have never built a DIY speaker project. I recently learned about this website so I figured I would bounce a few questions of of the experts to see what kind of feedback I get.

I am leaning towards building the "Cynosure" project that is posted on Parts Express:

http://www.partsexpress.com/projectshowcase/cynosure/index.cfm

I have concerns about the frequency response graph of this project:

Frequency Response

What I am interested in is what you all think of this project. I like the idea of the wide, very low profile enclosure. I am open to other speaker options.

Also, I believe that I will build JUST this center channel at first but what do you all think of possibly mating this speaker with some surrounds? Can I do a MTM or a MMT, or a MMMT using the same drivers? I really don't know what I am doing...YET so I am just hoping that these forums will help me end up with a successful DIY project.

Thanks

 

[GBBinaural]

Bump...

My concerns about the frequency response is that it varies from ~84db to ~91db. That seems like a bit much but I am a newbie so I am hoping that someone can decipher it a bit for me.

Thanks

 

[planet10]

My opinion: MTMs already have issues. The person who gave us sideways MTMs shoild be pilloried... This one just makes everything worse. A single one of the TBs should be better sonically.

The FR isn't all that bad... ignore the LF bump and it is ~+/- 3dB

dave

 

[GBBinaural]

Well...at least you are honest. Do most people feel that way about horizontal MTM's? This particular project does state that it turned out to have exceptional off axis performance. The crossover design is limiting each "pair" of speakers (outside, middle, inside) to a certain range does that help at all with your extra disdain since this is a MMMTMMM design?

I really appreciate the response. I am open to ANYTHING really...I just know that I want a nice sounding center channel that I can incorporate into a fireplace mantle. That is why it needs to be low profile.

As far as the frequency response goes. It may be not be "all that bad" but is it something that should be a good bit better if possible?

 

[planet10]

Do most people feel that way about horizontal MTM's? This particular project does state that it turned out to have exceptional off axis performance. The crossover design is limiting each "pair" of speakers (outside, middle, inside) to a certain range does that help at all with your extra disdain since this is a MMMTMMM design?

A lot of people feel the same as i about horizontal MTMs (i'm personally not a fan of vertical MTMs either), but a lot of people are also swayed by the fact that there are so many hirizontal centres out there (only way the manufacturers can fit something that looks like the surrounds on top of the TV. "More drivers has to be better doesn't it..."

The power tapering certianly means the designer thot about the problem, The exceptional off axis is probably in the vertical... the whole idea behind an MTM is to get symetrical and limited vertical dispersion and wide horizontal dispersion... turning it on its side is counter to the whole concept.

I really appreciate the response. I am open to ANYTHING really...I just know that I want a nice sounding center channel that I can incorporate into a fireplace mantle. That is why it needs to be low profile.

I'm a full-range guy. I'd say get an FE127 and put it into the 4.5 liter box... actually i firmly hold that -- given you aren't jamming people into the "poor seats" -- that no centre (ie a virtual centre) is the best centre.

IAs far as the frequency response goes. It may be not be "all that bad" but is it something that should be a good bit better if possible?

Have a look at the real world measurements of some of the big buck speakers in stereophile or hi-fi news... FR is just one of many important parameters in a speakers performance... and in the immortal words of Ed Schilling "i can make the measuremenst look anyway i want"

Further, if that FR is a measure and not a sim, everything below 300 Hz has to be taken with a grain of salt (maybe a whole box given we don't know their context)

Whenever i see a speaker with a passive XO & ruler flat FR i start getting worried... if the XO is simple i consider it excellent design... if it is complex then i wonder how much of the life of the speaker has been sucked out of it.

dave

 

[Scottmoose]

True. If you really want a centre channel (as a fan of 1970s Quad I'm with Dave -they improve dialogue imaging for off-axis viewers / listeners, beyond that, I can live cheerfully without them), then a 127 or 167 in a sealed box would be a good choice providing you're not trying for 120db peaks. I don't like horizontal arrays of drivers like that -dispersion is not going to be great IMO. Still, YMMV. Some people like them, though that might be because they haven't heard anything else? The 'stretching' of the image can be rather disconcerting, to my ears.

Ed's right about the FR graphs. Admiral John Fisher once commented 'When I was Controller, I had an excellent secretary. When I asked him for facts, he asked me what it was I wanted to prove! There is no doubt facts are most misleading.' Beware taking them at face value, unless you have the background detail / context, and also know how to interpret from that what is happening and why.

 

[GBBinaural]

I am continuing to learn more and more about loudspeaker design. I appreciate all of the responses so far. I have a new question now. I would like to input this project into a software solution (Speaker Workshop). Would it be possible to actually do that in this free software given the complexities of this speaker? Below is the crossover design:

Crossover - Cynosure

Can this crossover be constructed in Speaker Workshop? I am a total newb so if anyone can walk me through this process that would be great.

Thanks

 

[badman]

Parts Express projects

These are typically terrible designs. Most of their 'designers' don't address the serious issues of diffraction, baffle step, other stuff.

Better diy is out there, projects like those at www.zaphaudio.com are a good start.

 

[Godzilla]

I dont have these anymore but they worked great in a 5.1

http://www.zillaspeak.com/recycledsystem.asp

TB Bamboo's are currently my left and right in my home theater system.

http://www.zillaspeak.com/Bamboo.asp

i would keep them and make a center also using one TB Bamboo driver. They are less fatiguing when used with solid state - like my cheapie Yamaha receiver - than any of the Fostex i have heard.

Just my 2 cents.

Godzilla

 

[GBBinaural]

I appreciate the fast response. I have taken a look at some of Zaph's projects and they seem to be well executed. I am however in a bit of a spot and I really need the overall style (IE...long short design) of the cynosure project since it is going to actually BE my fireplace mantle. What I am trying to do is get THAT project into a loudspeaker design software package so I can begin to learn what happens to response curves when the crossover and or speakers are altered. I am not dead set on building that exact project but it will be something very similar. Any help on how to build that type of crossover in Speaker Workshop would be great.

 

[planet10]

since it is going to actually BE my fireplace mantle

You may need to rethink the project entirely then. I have a cliebt that sets his centre on the mantle, and he has to remove it anytime he fires up the fireplace because it gets hot. If you do go ahead you may want to buy a couple cases of drivers because you could well need to replace them regularily as they go off song from the fireplace heat (& smoke unless you have an insert) or just die.

dave

 

[GBBinaural]

HMMM...I guess that is a possibility. I do not expect to burn many fires however. I would imagine that quite a few people though have a setup that requires a Plasma type TV or in my case a projector screen on the same wall as a fireplace. In that case one would really need a solution to not have a large cube sitting in front of the fireplace. The design that I was considering would allow me to remove the speaker from the mantle area if needed. What I am trying to do is build the crossover from this project in the Speaker Workshop software but I am a total newb so I was hoping for some help on how or IF this can be achieved or if I would need a different software package. I will continue to browse the tutorials that I have found for Speaker Workshop...Thanks for all of the responses.

 

[LAL]

Well, I am going to buck the trend here. I am currently using 4 of the four inch Tangband titanium full range drivers closely spaced in a horizontal array for a center channel. They sound fine. Voices are exceptionally clear. The four will move lots of air without distortion when crossed over to a sub at 80HZ. I know all about comb filtering theory but I am not entirely convinced that the ear hears the way the microphone measures. I suggest you try it this way. If you don't like it you can use the drivers for your LR and surrounds. Unless your listening position is considerably off axis from the center channel speaker I think you will like it.

 

[planet10]

Unless your listening position is considerably off axis from the center channel speaker I think you will like it.

And unless your listening position is considerably off axis i think a virtual centre is the best centre....

dave

 

[MPM]

Well, I am going to buck the trend here. I am currently using 4 of the four inch Tangband titanium full range drivers closely spaced in a horizontal array for a center channel. They sound fine. Voices are exceptionally clear. The four will move lots of air without distortion when crossed over to a sub at 80HZ. I know all about comb filtering theory but I am not entirely convinced that the ear hears the way the microphone measures. I suggest you try it this way. If you don't like it you can use the drivers for your LR and surrounds. Unless your listening position is considerably off axis from the center channel speaker I think you will like it.

Any specs and/or pics of your enclosure? Would love to see it. I'm working on something similiar but with 3" tb drivers in a vertical array of 4. Will be my new computer speakers.

 

[GBBinaural]

LAL...I am interested in your project as well. One of the first things that I am hoping to do once I learn how to build crossovers in Speaker Workshop is to use some 4" drivers to see what the results are looking like. Speaking of which...it is a bit surprising that people always respond and just weigh in on the system but nobody actually answers the question being asked which was....

Can I build a crossover as complex as the one used in the Cynosure project in Speaker Workshop?

I definitely appreciate all of the opinions on the project and I very well may end up building something totally different but I have an idea of what I need to do and I am just trying to learn all I can about things like crossover design.

 

[LAL]

MPN
I have no pictures. I have been experimenting with various cabinet configurations using the TB titanium drivers in short arrays, both horizontal and vertical(as well as in various single driver cabinets). Ultimately I am restricted to a center channel cabinet no taller than 7 inches which is why the horizontal array design appealed to me. This was prompted by the PE center channel using the 3 inch TB and Roger Russell's line array using full range 3 inch drivers, the IDS-25.

GB Binurnal
I am not the guy to ask about building crossovers. I have built lots of speakers both big and small but have always used a kit and have let the kit designer assemble the crossover. You should be aware that crossover design done well is difficult and time consuming and that no computer program alone will do it for you. That's not to say that you should not have some fun with it yourself, but if you really want it done right then I would leave it to the experts. That is one reason why I am enjoying playing around with the extended range drivers with no crossovers. That and the fact that I really am impressed with the sound quality that single driver systems can provide.

 

[MPM]

MPN
This was prompted by the PE center channel using the 3 inch TB and Roger Russell's line array using full range 3 inch drivers, the IDS-25.

You and me both, I just haven't built any projects yet. I personally like a soft topend(speakers that is). I would like to hear an IDS-25 type speaker with the same driver they used in the cynosure. Use the phantom center channel and some type of surrounds with the same driver. Sounds expensive to me.

 

[santiu]

Came across this thread and thought i'd chime in as I just built one of these speakers over the long weekend. I bought all the parts for it years ago when I had just started to get into DIY speakers (project was chosen almost solely because the speaker looked cool) but never got around to actually building the damn thing. Finally had some free time this holiday season and put the sucker together. The speaker does indeed look very cool (at least to me).

Sound-wise I think the speaker performs quite well. Even though the speaker is very wide, the sound is still well focused. I'm actually very impressed with that little neo tweeter, it's very pleasant sounding. The speaker also does a great job of playing music. Granted, the Cynosure replaced my roommates old Yamaha HTiB center channel, so i imagine just about anything would have sounded worlds better. Off-axis performance is nothing to write home about. It's not horrendous, but it's not amazing either.

I'm sure there are better designs out there. Now that I've learned more over the years, I don't think i would build another MTM on it's side style center. But I had the parts, and figured I'd give it a try. Overall, I'm quite happy with the results.

On a construction side note, this was my first experience with thin, flimsy, flat mounting flanges like the Tang Band W3-926S has. Personally i found these to be a total pain to work with and don't look very nice either.

 

[John L]

I dont have these anymore but they worked great in a 5.1

http://www.zillaspeak.com/recycledsystem.asp

TB Bamboo's are currently my left and right in my home theater system.

http://www.zillaspeak.com/Bamboo.asp

i would keep them and make a center also using one TB Bamboo driver. They are less fatiguing when used with solid state - like my cheapie Yamaha receiver - than any of the Fostex i have heard.

Just my 2 cents.

Godzilla

That fleckstone finish on your center 'dialogue' speaker looks like a piece of styro-foam that has been sculptured to taste. I love it. Do they really look that way in real life like they do in the pictures?

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An externally hosted image should be here but it was not working when we last tested it.