All of the above, especially the graphics, help explain a lot - thanks!
One right now, a Rythmik F12. I plan to get a second.
Are there other woofers that might be a compromise of the transient response of the seas with the sensitivity of the Audax (also about the same price)?
btw. Where in Canada are you (I'm in Calgary)?
For the most part all frequencies below this point will wrap. There will be some ripple in the diffraction response and the subsequent reflections will cause comb filtering down to the point where the wall causes clean reinforcement. Within this range you may have issues but there are ways to minimise them.
Unfortunately, I find myself presently in the greater Toronto area. Uhg. I used to live in Whistler - now that was something special.
The reason I asked about 2 subs is because of LF localization. If you have 2 of them, they can be placed beside your mains (altho with other trade-offs possibly) and then you may xo a little higher than 80Hz without a problem, which would bring the Audax woofers sealed back into the running, for example. But if memory still serves, the Rythmik's don't like to go that high.
What was your goal for box volume for the 2 woofers?
The reason I asked about 2 subs is because of LF localization. If you have 2 of them, they can be placed beside your mains (altho with other trade-offs possibly) and then you may xo a little higher than 80Hz without a problem, which would bring the Audax woofers sealed back into the running, for example. But if memory still serves, the Rythmik's don't like to go that high.
What was your goal for box volume for the 2 woofers?
While personally I think the whole sealed/ported argument is a little ridiculous. and older then dirt. If you're swayed by it, there are plenty of 6.5" woofers with an acceptable roll off and decent sensitivity.
The Madisound Speaker Store
A pair in 1 ft3 sealed gets an F3 of 67hz.
The Madisound Speaker Store
A pair in 1 ft3 sealed gets an F3 of 67hz.
Just stating my preference for sealed and thinking it would be the better choice for this project not only because of the improved transient response but because of size considerations as well.
Jay, that ScanSpeak is a nice affordable driver but I'm wondering if the larger outside diameter (180cm vs 146cm for the Seas) and box volume (for the pair, 28L vs 16L for the Seas) might be unsuitable for the OP's application of a bookshelf 3 way. I'm figuring baffle dimensions and box volume (or WAF in other words) might be a prime consideration and I'm trying to find out that parameter right now before I make any more recommendations.
Jay, that ScanSpeak is a nice affordable driver but I'm wondering if the larger outside diameter (180cm vs 146cm for the Seas) and box volume (for the pair, 28L vs 16L for the Seas) might be unsuitable for the OP's application of a bookshelf 3 way. I'm figuring baffle dimensions and box volume (or WAF in other words) might be a prime consideration and I'm trying to find out that parameter right now before I make any more recommendations.
That ScanSpeak looks quite interesting. As I am sure you guys have listened to many more drivers than I have, I have a question: looking at ScanSpeak, for a design where the woofer's role is 80 - 500Hz, what would a Revelator or Illuminator provide over this Discovery (Discovery has obbvious price and sensitivity advantages, and appears to have flatter FR)?
As to size, I had been assuming that with two woofers, a mid and tweeter, along with a front slot port (I had assumed i would need a port, and with against the wall placement it would have to be front ported) that these would be just under 24" tall. And of course, for WAF if they could be closer to 20" would be better (so if sealed works that would eliminate an inch or two).
Jay, the parameters in your show quite a bit lower efficiency for the 8434 than at Madisound - why? Are those Zaph's measurements?
As to size, I had been assuming that with two woofers, a mid and tweeter, along with a front slot port (I had assumed i would need a port, and with against the wall placement it would have to be front ported) that these would be just under 24" tall. And of course, for WAF if they could be closer to 20" would be better (so if sealed works that would eliminate an inch or two).
Jay, the parameters in your show quite a bit lower efficiency for the 8434 than at Madisound - why? Are those Zaph's measurements?
Those are Zaphs measurements.
The fiberglass cone SS developed is pretty great, showing an incredibly damped top end. The motor design is much more basic, there is rising distortion in the mid range, but as a woofer that wont be an issue. The higher end SS's have lower overall distortion, more xmax, and usually stronger motors.
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Rick, I'm going to apologize in advance because I think I'm going to muddy the waters a bit for you here.
First let me say that I like your choice of the Audax and Seas for your purposes. The way you want to use them makes good use of their strengths. Again, I'd probably look at a different tweeter though.
If you went with internal dimensions of something like 7x20x11 inches, you get about 25L to play with. You need about 16L sealed for the 2 Seas, maybe 2L for the Audax and now you have 7L left over for bracing, driver volumes, xo's, internal mid chamber walls, wall damping etc. So something like that should easily work nicely especially with the xo's being handled by a professional.
However, I haven't heard them myself. I know they’re good but I don’t know exactly how good. Tony Gee likes the Seas in this monitor http://www.humblehomemadehifi.com/download/Humble%20Homemade%20Hifi_Nebular%20Monitor_copy.pdf, and Linkwitz uses it in his PLUTO-2.1 omni-directional loudspeaker. What I do know is what I use – the Revelators in Zaph|Audio - ZD5 - Scan Speak 15W8530K00 and Vifa XT25. I’m running them sealed in the best cabinet I could build, crossed to a sub at 80 Hz and they are jaw droppingly good - detail, dynamics, imaging, instruments and voices emerging out of an inky dark, soundless background.
Now, let's stop for a second and do some accounting.
Using current prices at Solen:
Audax = $93
Seas = 2 x $99 = $198
And I’m going to add in a guestimate of the extra xo for a 3-way = $50
So you’re looking at around $340 to cover between about 80 to 2500 Hz.
Now here are a few of the big boys that you can get for the same kind of money that will cover the same range.
https://www.solen.ca/pdf/scan/18w8531g00.pdf - $228
https://www.solen.ca/pdf/sb/Satori/mw16p.pdf - $284
The Madisound Speaker Store - $320 (from the States tho and will probably need more work in the xo to kill the HF resonance)
All of those will go below 80 Hz sealed in volumes that will work for you. You'll only need 1 and use it in a 2-way, but believe me, that will be more than adequate.
You should take a serious look at the Kairos using the Satori by a very well respected designer - http://meniscusaudio.com/images/The%20Kairos%20Monitor%20Speaker%20by%20Jeff%20Bagby.pdf. Yes I know it's ported, but you could just as easily change that to a sealed allignment.
Not that I think that distortion measurements tell the whole story, but they are a good starting point. Below are the graphs for the Seas L16RN-SL again, then the Scan Discovery again, then the Revelator 18W8531G00, followed by the Satori and then the Scan 18WU4741T (the 4 ohm version). Look in particular at the 3rd harmonic in the usable frequency range. The winner is number 4.
First let me say that I like your choice of the Audax and Seas for your purposes. The way you want to use them makes good use of their strengths. Again, I'd probably look at a different tweeter though.
If you went with internal dimensions of something like 7x20x11 inches, you get about 25L to play with. You need about 16L sealed for the 2 Seas, maybe 2L for the Audax and now you have 7L left over for bracing, driver volumes, xo's, internal mid chamber walls, wall damping etc. So something like that should easily work nicely especially with the xo's being handled by a professional.
However, I haven't heard them myself. I know they’re good but I don’t know exactly how good. Tony Gee likes the Seas in this monitor http://www.humblehomemadehifi.com/download/Humble%20Homemade%20Hifi_Nebular%20Monitor_copy.pdf, and Linkwitz uses it in his PLUTO-2.1 omni-directional loudspeaker. What I do know is what I use – the Revelators in Zaph|Audio - ZD5 - Scan Speak 15W8530K00 and Vifa XT25. I’m running them sealed in the best cabinet I could build, crossed to a sub at 80 Hz and they are jaw droppingly good - detail, dynamics, imaging, instruments and voices emerging out of an inky dark, soundless background.
Now, let's stop for a second and do some accounting.
Using current prices at Solen:
Audax = $93
Seas = 2 x $99 = $198
And I’m going to add in a guestimate of the extra xo for a 3-way = $50
So you’re looking at around $340 to cover between about 80 to 2500 Hz.
Now here are a few of the big boys that you can get for the same kind of money that will cover the same range.
https://www.solen.ca/pdf/scan/18w8531g00.pdf - $228
https://www.solen.ca/pdf/sb/Satori/mw16p.pdf - $284
The Madisound Speaker Store - $320 (from the States tho and will probably need more work in the xo to kill the HF resonance)
All of those will go below 80 Hz sealed in volumes that will work for you. You'll only need 1 and use it in a 2-way, but believe me, that will be more than adequate.
You should take a serious look at the Kairos using the Satori by a very well respected designer - http://meniscusaudio.com/images/The%20Kairos%20Monitor%20Speaker%20by%20Jeff%20Bagby.pdf. Yes I know it's ported, but you could just as easily change that to a sealed allignment.
Not that I think that distortion measurements tell the whole story, but they are a good starting point. Below are the graphs for the Seas L16RN-SL again, then the Scan Discovery again, then the Revelator 18W8531G00, followed by the Satori and then the Scan 18WU4741T (the 4 ohm version). Look in particular at the 3rd harmonic in the usable frequency range. The winner is number 4.
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I hope people won't mind if I approach this differently. On the technical details and components you seem to be getting good advice. But I think as much as we need to consider the technical aspects and components, we need to treat this as if you were going to a HiFi shop and buying speakers. You still need to make the same consideration.
When advising people on buying audio equipment is
- Budget
- Circumstances
- Goals
Under Goals would be preferences and priorities. Can't get what you want until you know what you want.
So, start with Budget, because that really defines the entire project.
Next, Circumstances, in what size room and for what type of music will the system be used? Further how do you listen - loud, modest, etc..? What type of music do you listen to - Rap/Dubstep/Techno/Club - have very different requirements than Jazz or Classical.
What are your priorities? That is, how big can the speakers be? Do you stress bass weight over clarity, or would you sacrifice a degree of bass weight if it brought you absolute clarity?
Tied in with this are preferences, they are similar, but not quite the same. Myself I prefer Floorstanding/Tower speakers, that's just the way it is. I prefer large drivers, though in today's market, 10", 12", and 15" bass drivers are all but gone. But it is still what I prefer.
Approaching a project in this fashion informs the design. It informs the choice of drivers. It informs the cabinet design.
In your original design, you were, based on the information I found, you are looking at 5" bass drivers and 4" midrange drivers? I'm not sure if that creates a balanced system. Though certainly it can be made to work.
Next, consider the cabinet. Starting with a 5" or 6.5" woofer, if we want the cabinets somewhat proportional, can you squeeze an additional 4" speaker on the front face and still maintain reasonable proportions of dimensions?
Next, why a 3-way? Personally I prefer 3-way because it make driver selection easier. With a midrange you can limit each driver to its optimal range. But the design is slightly more dicey.
Next, the drivers have to be relevant to the design goals. The drivers for a 3-way Low-Bass, Mid-Bas, Tweeter system are much different than Woofer, Mid-Range, Tweeter, which in turn are different than a Woofer, Tweeter, Super-Tweeter design.
Any decision is the right decision if it meets the design objectives. In your case you seem to be looking at a Woofer, Mid-Range, Tweeter configuration.
So, we start there. Assuming you can come up with workable cabinet dimensions, you are probably better off with a 3" Cone Midrange or a 2" dome Midrange.
Though not etched in stone, using the Golden Ration (1.618), each progressively longer cabinet side should be 1.62 larger than the previous.
So, if we assume a 6.5" bass driver, we need a cabinet of about 8" wide. So, 8" x 1.62 = 9.62" Deep, 9.62" x 1.62 = 15.58" High. Again, not etched in stone, but it sets a starting point.
So, dimensions (ball park) 8" x 9.62" x 15.58".
Is that enough room for a 3" or 4" Mid-Range driver combined with a 6.5" bass driver. Do keep in mind it is possible to get very good yet very small tweeters. Here is an example -
Dayton Audio ND16FA-6 5/8" Neodymium Dome Tweeter 275-025
Vifa BC25SC55-04 1" Square Frame Tweeter 264-1024
Dayton Audio ND20FB-4 Rear-Mount 3/4" Neodymium Dome Tweeter 275-035
There are still small but more expensive higher quality tweeters available. This just illustrates the point.
What I'm getting at is that you need to work out the design in concept weighing all the factors of price, goals, circumstances, etc...
Then you need to examine the mechanical realities. To use an extreme example, you can't want a 10" bass driver and still demand a tiny cabinet. The physical reality has to match the conceptual reality.
Then once you have the concept, you start searching for drivers that serve both the budget and the design concept combined with the physical realities.
One additional think to consider for Bass Reflex (ported) cabinets is - do you actually have room for it? Likely with a 3-way, the port is going to need to be on the back. The Port Diameter and the Port Depth will depend on the size of the cabinet and the frequency you want it to resonate at.
As an example, take a Dayton Classic 6.5" bass driver -
Dayton Audio DC160-8 6-1/2" Classic Woofer 295-305
It has an (fs) resonance frequency of about 34hz. That is roughly the range where you would want the cabinet to resonate, and that pretty much reflects the lowest frequency the speaker is capable of.
Take the cabinet dimension I gave you, which are internal dimensions. Then subtract an estimate of the Woofer volume (space) from the cabinet volume. Now use that volume to determine the diameter and depth of the port necessary to make that size cabinet resonate at the desired frequency.
You have about a 0.75 ft³ cabinet. We will subtract .015 Ft³ for the volume displaced by the woofer. That leaves 0.6 ft³.
Using this port calculator -
LinearTeam
Let's see what the possibilities are -
A single 3" diameter port tuned to 36hz would need to be 22 inches long.
A single 2" diameter port tuned to 36hz would need to be a modest 9.4 inches long.
A single 2" port tuned to 45hz would need to be 5.5 inches long.
One additional consideration, the Vas specification of the Dayton speakers is 0.87 ft³. For what it is worth.
Things to consider.
LinearTeam
Before you start choosing drivers, you need to take all these things into consideration.
First, treat it like you are buying a speaker and consider everything you would consider when doing that.
Next, work out the physical realities with potential drivers you are considering.
Next, work out the crossover frequencies relative to the drivers you have pick and that are consistent with the design concept.
I don't know if this is any help, and you are free to accept it or reject it as you see fit. But do give it some consideration.
For what it is worth.
Steve
When advising people on buying audio equipment is
- Budget
- Circumstances
- Goals
Under Goals would be preferences and priorities. Can't get what you want until you know what you want.
So, start with Budget, because that really defines the entire project.
Next, Circumstances, in what size room and for what type of music will the system be used? Further how do you listen - loud, modest, etc..? What type of music do you listen to - Rap/Dubstep/Techno/Club - have very different requirements than Jazz or Classical.
What are your priorities? That is, how big can the speakers be? Do you stress bass weight over clarity, or would you sacrifice a degree of bass weight if it brought you absolute clarity?
Tied in with this are preferences, they are similar, but not quite the same. Myself I prefer Floorstanding/Tower speakers, that's just the way it is. I prefer large drivers, though in today's market, 10", 12", and 15" bass drivers are all but gone. But it is still what I prefer.
Approaching a project in this fashion informs the design. It informs the choice of drivers. It informs the cabinet design.
In your original design, you were, based on the information I found, you are looking at 5" bass drivers and 4" midrange drivers? I'm not sure if that creates a balanced system. Though certainly it can be made to work.
Next, consider the cabinet. Starting with a 5" or 6.5" woofer, if we want the cabinets somewhat proportional, can you squeeze an additional 4" speaker on the front face and still maintain reasonable proportions of dimensions?
Next, why a 3-way? Personally I prefer 3-way because it make driver selection easier. With a midrange you can limit each driver to its optimal range. But the design is slightly more dicey.
Next, the drivers have to be relevant to the design goals. The drivers for a 3-way Low-Bass, Mid-Bas, Tweeter system are much different than Woofer, Mid-Range, Tweeter, which in turn are different than a Woofer, Tweeter, Super-Tweeter design.
Any decision is the right decision if it meets the design objectives. In your case you seem to be looking at a Woofer, Mid-Range, Tweeter configuration.
So, we start there. Assuming you can come up with workable cabinet dimensions, you are probably better off with a 3" Cone Midrange or a 2" dome Midrange.
Though not etched in stone, using the Golden Ration (1.618), each progressively longer cabinet side should be 1.62 larger than the previous.
So, if we assume a 6.5" bass driver, we need a cabinet of about 8" wide. So, 8" x 1.62 = 9.62" Deep, 9.62" x 1.62 = 15.58" High. Again, not etched in stone, but it sets a starting point.
So, dimensions (ball park) 8" x 9.62" x 15.58".
Is that enough room for a 3" or 4" Mid-Range driver combined with a 6.5" bass driver. Do keep in mind it is possible to get very good yet very small tweeters. Here is an example -
Dayton Audio ND16FA-6 5/8" Neodymium Dome Tweeter 275-025
Vifa BC25SC55-04 1" Square Frame Tweeter 264-1024
Dayton Audio ND20FB-4 Rear-Mount 3/4" Neodymium Dome Tweeter 275-035
There are still small but more expensive higher quality tweeters available. This just illustrates the point.
What I'm getting at is that you need to work out the design in concept weighing all the factors of price, goals, circumstances, etc...
Then you need to examine the mechanical realities. To use an extreme example, you can't want a 10" bass driver and still demand a tiny cabinet. The physical reality has to match the conceptual reality.
Then once you have the concept, you start searching for drivers that serve both the budget and the design concept combined with the physical realities.
One additional think to consider for Bass Reflex (ported) cabinets is - do you actually have room for it? Likely with a 3-way, the port is going to need to be on the back. The Port Diameter and the Port Depth will depend on the size of the cabinet and the frequency you want it to resonate at.
As an example, take a Dayton Classic 6.5" bass driver -
Dayton Audio DC160-8 6-1/2" Classic Woofer 295-305
It has an (fs) resonance frequency of about 34hz. That is roughly the range where you would want the cabinet to resonate, and that pretty much reflects the lowest frequency the speaker is capable of.
Take the cabinet dimension I gave you, which are internal dimensions. Then subtract an estimate of the Woofer volume (space) from the cabinet volume. Now use that volume to determine the diameter and depth of the port necessary to make that size cabinet resonate at the desired frequency.
You have about a 0.75 ft³ cabinet. We will subtract .015 Ft³ for the volume displaced by the woofer. That leaves 0.6 ft³.
Using this port calculator -
LinearTeam
Let's see what the possibilities are -
A single 3" diameter port tuned to 36hz would need to be 22 inches long.
A single 2" diameter port tuned to 36hz would need to be a modest 9.4 inches long.
A single 2" port tuned to 45hz would need to be 5.5 inches long.
One additional consideration, the Vas specification of the Dayton speakers is 0.87 ft³. For what it is worth.
Things to consider.
LinearTeam
Before you start choosing drivers, you need to take all these things into consideration.
First, treat it like you are buying a speaker and consider everything you would consider when doing that.
Next, work out the physical realities with potential drivers you are considering.
Next, work out the crossover frequencies relative to the drivers you have pick and that are consistent with the design concept.
I don't know if this is any help, and you are free to accept it or reject it as you see fit. But do give it some consideration.
For what it is worth.
Steve
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I came here asking for thoughts and opinions of those who klnow more than me - I appreciate all of them.
The reasoning for a 3-way is that I want the centre speaker to be a W-T/M-W instead of an M-T-M for both midrange clarity and reduced comb filtering issues.
So to get perfect timbre match across the front, that means the L/R mains are also 3-way, with the same drivers.
That's my thinking - as flawed as it may be
I'll look into the other suggestions more too.
Thanks for all feedback and suggestions.
Lots there to absorb Steve - thanks.
Some of the goals, were in my last response to jReave; I'll post others later (must go outside for a while now).
Everyone - please keep the great food for thought coming.
Actually, the horizontal Center speaker is an inherently poor design. Stand it on end, and it works much better. But, there are certain practical realities that dictate the a Center speaker must be what a Center speaker is.
One of the problems is that you have two bass drivers set apart on a horizontal plane. Why TWO bass drivers, simply two small drivers fit in the cabinet under your TV better than one larger bass drive.
This is one of the 'Circumstance' aspects I was talking about. If you have more space available then consider a bigger single bass driver to the side of a vertical Mid-Range/Tweeter configuration.
Also, some people, designers, feel that you have fewer conflicts if you have twin bass drivers in a Low-Bass/Mid-Bass configuration or in a HALF-way configuration, as in a 2.5-way or a 3.5-way. Because the bass driver only run in parallel in a limited range of frequencies, you have less conflict between them.
Also, keep in mind that small changes in speaker diameter make big changes in cone surface area. As an example, more or less, a 6.5" woofer is 1.7 times larger than a 5" bass driver. So one 6.5" is close to TWO 5". An 8" woofer is 3.3 times larger than a 5" speaker and 1.7 times larger than a 6.5" speakers.
You can get a relative estimate of the various speaker sizes, by simply calculating the Area of a circle of that given diameter.
Others may have more to say on this, but I suspect a better Center speaker would be a 6.5" bass or an 8" bass combined with a vertical Midrange/Tweeter combination.
Assuming of course, you have enough room for such a speaker.
Steve
Understood, 3 identical vertical speakers is the best scenario...
...but reality is all about compromises.
Another key reason for the two drivers is to get the sensitivity up.
But in a 3-way design, with the woofers only dealing with 500Hz and less, as long as the CTC spacing of the woofers is less than 27" (one wavelength at 500Hz) there should be a problem, right?
So long as the single woofer has sufficient sensitivity.
I think that the height of the tweeter and midrange will likely dictate the height of the centre speaker - certainly create enough room for a 6 1/2" or 7", probably an 8".
Ahhh.... a center channel too. Now it makes more sense.
I am completely with you on your center channel goals. I'll give it some more thought, but I think your 3-way design is probably the best way to achieve timbre matching around the multi-channel soundstage and when it comes down to it, the same vertically oriented speaker as a center channel just won't fit/work for many wifes, er.... I mean living rooms.
Note however that the timbre matching may not be absolutely perfect. Because of the differences in baffle widths and even in placement between speakers, diffraction effects will be different and the xo's will also have to be designed slightly differently. But here you're at an advantage because you're getting the xo's and voicing done by an expert. BTW, with your mains and/or surrounds, if you're designing/building the boxes, I'd suggest you choose a baffle width that is equivalent to the mid-woofer xo point, ie. about 500 Hz which means about 9" wide - perhaps 7" internal with 1" thick sides. This way simplifies the xo.
So back to the sealed vs sensitivity trade-off. If you can hear any differences, they'll only be subtle but I think the transient response is more noticeable than whether it's 86 or 92 dB in sensitivity. Unless of course your amp doesn't have enough power. But I doubt you need peaks of any more than 105dB, and starting with 86dB sensitivity, that's achieved with about 75 watts. 80 dB with only 1 woofer is another story though - I'd stick with 2 for the CC as well.
You can actually fit a 180mm driver onto a 9" wide baffle and that opens up a few more possible candidates for woofers, but of course the main's baffles will also need to be taller by an inch or 2 as well. Also, I figure that you probably know this already but just in case.... 1 of the beauties of those Seas drivers is the larger cone area on a smaller frame. It's almost like a driver 1 size larger. Lots of excursion as well.
I am completely with you on your center channel goals. I'll give it some more thought, but I think your 3-way design is probably the best way to achieve timbre matching around the multi-channel soundstage and when it comes down to it, the same vertically oriented speaker as a center channel just won't fit/work for many wifes, er.... I mean living rooms
.Note however that the timbre matching may not be absolutely perfect. Because of the differences in baffle widths and even in placement between speakers, diffraction effects will be different and the xo's will also have to be designed slightly differently. But here you're at an advantage because you're getting the xo's and voicing done by an expert. BTW, with your mains and/or surrounds, if you're designing/building the boxes, I'd suggest you choose a baffle width that is equivalent to the mid-woofer xo point, ie. about 500 Hz which means about 9" wide - perhaps 7" internal with 1" thick sides. This way simplifies the xo.
So back to the sealed vs sensitivity trade-off. If you can hear any differences, they'll only be subtle but I think the transient response is more noticeable than whether it's 86 or 92 dB in sensitivity. Unless of course your amp doesn't have enough power. But I doubt you need peaks of any more than 105dB, and starting with 86dB sensitivity, that's achieved with about 75 watts. 80 dB with only 1 woofer is another story though - I'd stick with 2 for the CC as well.
You can actually fit a 180mm driver onto a 9" wide baffle and that opens up a few more possible candidates for woofers, but of course the main's baffles will also need to be taller by an inch or 2 as well. Also, I figure that you probably know this already but just in case.... 1 of the beauties of those Seas drivers is the larger cone area on a smaller frame. It's almost like a driver 1 size larger. Lots of excursion as well.
and when it comes down to it, the same vertically oriented speaker as a center channel just won't fit/work for many wifes, er.... I mean living rooms
The only way that could really work is with an AT screen. Any other way and you'd have to raise the screen too high. I think the compromise of a well designed centre (hence all of this effort) will make for a better HT experience than having the screen a few feet higher than it should be.
Good points - when this finally turns into a real project i will bring them up with Dennis and Jim.
Actually, according to Peak SPL Calculator (spl calculator); an 86db efficient speaker, against a wall with 75 watts would only give 105db if you are 4 feet away. I expect to be 15 feet away, so 86db efficient needs more like 850 watts to hit 105db peaks. Getting it to 90db efficient only needs 300 watts, and 92 gets it down to 200.
Then the discussion becomes, does that 1 speaker need to hit 105db by itself? How much do the other speakers contribute, or do they? That discussion gets much more convoluted.
The Seas are really nice - I'm just a bit concerned about the sensitivity. 2 together just might do the trick.
Now those SS Discovery seems worth more exploring...
Thanks Jay - I understand some of that
Since I'm not a speaker designer, just an HT and audio enthusiast trying to figure out the best drivers for a HT and m-ch music system upgrade, in layman's terms...
...what difference would I experience in the 80 - 500 Hz range when listening to Dark Side of the Moon 5.1 SACD if my speakers had Revelator 18W/8531G instead of Discovery 18W/8434G00?
That could help me understand some of the differences between a $70 and a $210 driver.
As far as distortion at Zaph's test level goes, there's practically no difference in that range of frequencies. What happens when the volume is cranked? Hard to say for sure, but the 8531 should hold together better.
The 8531 has a serious advantage if used in a wider range, as it will go deeper in a smaller box with a lot more authority, and its distortion profile stays completely clean (and low) until it drops off.
The 8531 has a serious advantage if used in a wider range, as it will go deeper in a smaller box with a lot more authority, and its distortion profile stays completely clean (and low) until it drops off.
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Two drivers vs one driver (unless I am mistaken) will only give you at 3dB boost in sensitivity. 3dB is twice the Acoustic Power, but it is only a slight increase in loudness.
This depends on how you wire the two bass drivers. If you wire them in parallel for a resulting 4 ohms, then you might get a bit more boost, but then your AV amp will have to drive 4 ohms - some can and some can't, and some can better than others.
Keep in mind the AV amp will adjust the amp channels to balanced Reference Levels at the Prime Seating Location. Plus or minus 3db or 6 db is not going to matter because the amp is going to compensate for it.
Both the Dayton Classic 6.5" and the Dayton Classic 5.25 inch have ~88db Sensitivities. But the 6.5" with about 1.6 times the cone area, will have an impedance of a solid 8 ohms. 88dB Sensitivity in general is on the high side for a Bass driver.
As far as a midrange, the Dayton Reference 3" full range combined with one of the many Dayton tweeter should work fine. Here are the specs on the 3" full range -
http://www.parts-express.com/pdf/295-380s.pdf
It is well functional from 130hz up to about 2Khz and generally functional up to about 8khz.
Keeping in mind the functional range has to exceed the working range. Meaning if you are crossing over at 500hz, the speaker should be functional down to about 250hz (more or less).
There is also a truncated version of the 3" speaker, that might buy you some space -
Dayton Audio RS75T-8 3" Reference Full-Range Driver Truncate 295-336
The Dayton Reference 4" Full Range -
Dayton Audio RS100-8 4" Reference Full-Range Driver 295-352
The frequency response on this is a little flatter than the 3", and it seem good from 100hz up to about 6khz, though it does go higher -
http://www.parts-express.com/pdf/295-352s.pdf
Next draw it out on some 1/4" x 1/4" graph paper to scale. You should be able to get some circle templates to very closely approximate the various speaker sizes.
Once you have that consider - ported or sealed? If ported - Front Port or Back?
What cabinet volume do you need to accommodate both the drivers and the ports?
From what I understand, the W(MT)W Center is configured that way not for acoustical perfection, but for visual appeal to the user. I suspect, though not as visually symmetrical, the design could just as easily be WW(MT).
Most of the design aspects of a Center speaker are for visual aesthetics, not sound quality.
Next, are you also building Front Left/Right speakers as well, or are you adding a Center to existing speakers? If you are building all three, then you want they all based around the same drivers and design.
Whether you can use Ported or Sealed, and Front Ported or Rear is another one of those circumstance driven aspects. Will the Center be in the open? On an open shelf under the TV? In a closed backed equipment cabinet? These all matter both when buying and when building. If there is a large center post in the back of the equipment stand, you probably don't want the port firing into that post.
If in a closed backed cabinet, then you probably don't want a ported cabinet at all.
Keep in mind, in a 5.1 Surround System, the bass is handled by the Sub and the Fronts. The Center speaker doesn't really need ultra-deep bass. If it has basic bookshelf bass or a bit less that is probably fine. I would say upper bass, and mid-range clarity are the most important factor, so don't get too hung up on great bass response for the Center, that will probably haunt you in the end.
As to the cost of the speakers, assuming a decent implementation, let me explain by analogy. If you meet are less knowledgeable person on stereo equipment and you tell them you have $5,000 stereo, there reaction is likely to be - Wow, that must be really loud - Wow, that must have incredible bass.
Well - No and No. A good system isn't any louder than a basic consumer system, and a good system doesn't have a lot of perceived bass. Bass is something rookies desire.
Bass, like sex, is something young men desire to excess.
What you get from better drivers very carefully implemented is CLARITY. Clarity of bass as much as clarity of mid-range and treble. If you want loud with intense bass, then build a low cost system. But if you want absolute clarity, then spend some cash.
Which bring us full circle to BUDGET. Budget frames everything and is the point to start.
Play a game with yourself. Ask yourself if you can spend $500 on a finished Center - Yes, No, or Maybe? One of those has to be the answer. If YES, then can you spend $1000 on just the finished Center - Yes, No, or Maybe? If the answer to $500 is NO, then can you spend $250 on a finished Center - Yes, No, or Maybe? Going by your gut, some number is going to feel good, and some number are going to make you feel uneasy. The UNEASY Feeling number are probably out.
So, even more so back to the beginning. Define the entire project - Center only, Front Only, Front and Center, or what...? You tell us.
Then the Budget? If your budget is too low for your design goals we will tell you. If your design needs some tweaking, we will help you.
First design in concept; what do I (you) envision the final system looking like? Bookshelf? Floorstanding? Finely crafted wood? Basic black boxes? Etc..?
Then design in size. What do I need to both fit and function in the space available? Another circumstance consideration.
Then design in components that meet the goals and budget.
Then design in details. Work out all the fine details and trust me there are hundreds more than you imagine. Workout the cabinetry. Workout the Crossover. Workout the misc hardware. Work out the aesthetics.
Then test, and start again. Based on what you have, what do you need to tweak to truly get what you want?
Keep going until your kids turn surly, and your wife threatens divorce, and your bank about is down to nothing, then you are done ...sort of ...more or less ... in a manner of speaking.
One last NOTE: The drivers I used were for purposes of illustration. There are plenty of other fine drivers out their, but you need to nail down your budget first. Then find drivers that fit both the budget and the design concept and goals. Nothing wrong with Dayton, I just have no idea of your budget, design concept, or goals, so take them as illustrative of my various points, and no more.
In one man's opinion.
Steve
This depends on how you wire the two bass drivers. If you wire them in parallel for a resulting 4 ohms, then you might get a bit more boost, but then your AV amp will have to drive 4 ohms - some can and some can't, and some can better than others.
Keep in mind the AV amp will adjust the amp channels to balanced Reference Levels at the Prime Seating Location. Plus or minus 3db or 6 db is not going to matter because the amp is going to compensate for it.
Both the Dayton Classic 6.5" and the Dayton Classic 5.25 inch have ~88db Sensitivities. But the 6.5" with about 1.6 times the cone area, will have an impedance of a solid 8 ohms. 88dB Sensitivity in general is on the high side for a Bass driver.
As far as a midrange, the Dayton Reference 3" full range combined with one of the many Dayton tweeter should work fine. Here are the specs on the 3" full range -
http://www.parts-express.com/pdf/295-380s.pdf
It is well functional from 130hz up to about 2Khz and generally functional up to about 8khz.
Keeping in mind the functional range has to exceed the working range. Meaning if you are crossing over at 500hz, the speaker should be functional down to about 250hz (more or less).
There is also a truncated version of the 3" speaker, that might buy you some space -
Dayton Audio RS75T-8 3" Reference Full-Range Driver Truncate 295-336
The Dayton Reference 4" Full Range -
Dayton Audio RS100-8 4" Reference Full-Range Driver 295-352
The frequency response on this is a little flatter than the 3", and it seem good from 100hz up to about 6khz, though it does go higher -
http://www.parts-express.com/pdf/295-352s.pdf
Next draw it out on some 1/4" x 1/4" graph paper to scale. You should be able to get some circle templates to very closely approximate the various speaker sizes.
Once you have that consider - ported or sealed? If ported - Front Port or Back?
What cabinet volume do you need to accommodate both the drivers and the ports?
From what I understand, the W(MT)W Center is configured that way not for acoustical perfection, but for visual appeal to the user. I suspect, though not as visually symmetrical, the design could just as easily be WW(MT).
Most of the design aspects of a Center speaker are for visual aesthetics, not sound quality.
Next, are you also building Front Left/Right speakers as well, or are you adding a Center to existing speakers? If you are building all three, then you want they all based around the same drivers and design.
Whether you can use Ported or Sealed, and Front Ported or Rear is another one of those circumstance driven aspects. Will the Center be in the open? On an open shelf under the TV? In a closed backed equipment cabinet? These all matter both when buying and when building. If there is a large center post in the back of the equipment stand, you probably don't want the port firing into that post.
If in a closed backed cabinet, then you probably don't want a ported cabinet at all.
Keep in mind, in a 5.1 Surround System, the bass is handled by the Sub and the Fronts. The Center speaker doesn't really need ultra-deep bass. If it has basic bookshelf bass or a bit less that is probably fine. I would say upper bass, and mid-range clarity are the most important factor, so don't get too hung up on great bass response for the Center, that will probably haunt you in the end.
As to the cost of the speakers, assuming a decent implementation, let me explain by analogy. If you meet are less knowledgeable person on stereo equipment and you tell them you have $5,000 stereo, there reaction is likely to be - Wow, that must be really loud - Wow, that must have incredible bass.
Well - No and No. A good system isn't any louder than a basic consumer system, and a good system doesn't have a lot of perceived bass. Bass is something rookies desire.
Bass, like sex, is something young men desire to excess.
What you get from better drivers very carefully implemented is CLARITY. Clarity of bass as much as clarity of mid-range and treble. If you want loud with intense bass, then build a low cost system. But if you want absolute clarity, then spend some cash.
Which bring us full circle to BUDGET. Budget frames everything and is the point to start.
Play a game with yourself. Ask yourself if you can spend $500 on a finished Center - Yes, No, or Maybe? One of those has to be the answer. If YES, then can you spend $1000 on just the finished Center - Yes, No, or Maybe? If the answer to $500 is NO, then can you spend $250 on a finished Center - Yes, No, or Maybe? Going by your gut, some number is going to feel good, and some number are going to make you feel uneasy. The UNEASY Feeling number are probably out.
So, even more so back to the beginning. Define the entire project - Center only, Front Only, Front and Center, or what...? You tell us.
Then the Budget? If your budget is too low for your design goals we will tell you. If your design needs some tweaking, we will help you.
First design in concept; what do I (you) envision the final system looking like? Bookshelf? Floorstanding? Finely crafted wood? Basic black boxes? Etc..?
Then design in size. What do I need to both fit and function in the space available? Another circumstance consideration.
Then design in components that meet the goals and budget.
Then design in details. Work out all the fine details and trust me there are hundreds more than you imagine. Workout the cabinetry. Workout the Crossover. Workout the misc hardware. Work out the aesthetics.
Then test, and start again. Based on what you have, what do you need to tweak to truly get what you want?
Keep going until your kids turn surly, and your wife threatens divorce, and your bank about is down to nothing, then you are done ...sort of ...more or less ... in a manner of speaking.
One last NOTE: The drivers I used were for purposes of illustration. There are plenty of other fine drivers out their, but you need to nail down your budget first. Then find drivers that fit both the budget and the design concept and goals. Nothing wrong with Dayton, I just have no idea of your budget, design concept, or goals, so take them as illustrative of my various points, and no more.
In one man's opinion.
Steve
Last edited:
BlueWizard,
The project is to upgrade the 5.0 parts of a current 5.1 (ultimately a 5.2). The current 5.0 is 3 Kef iQ3 across the front and a pair of iQ1 in the rear. The current system sounds great, the upgrade will have to be a significant step up sonically in order to be worthwhile.
The fronts will be against a wall, so they will be either sealed or front-ported (I have always assumed that in order to get a quality 6 1/2" driver to crossover to a sub at 80Hz that it will be ported - some of this discussion has been otherwise, and i am open to reasons to go sealed).
The use is both HT and multi-channel SACD and DVD-A.
I do not have the skills to build my own speakers, but I have the grey matter and desire to explore requirements and come up with driver selection. I will have the speakers built by Jim Salk (Salk Sound) whose crossovers get designed by Dennis Murphy (Philharmonic Audio); the first project I did with the two of them turned into the WOW1 Mini Monitor for Salk Sound.
As to budget, it is more determine what the upgrade will cost, then save to get it. I suspect the 5.0 will cost in the $3500 - $6000; largely dependent on final driver selection.
The project is to upgrade the 5.0 parts of a current 5.1 (ultimately a 5.2). The current 5.0 is 3 Kef iQ3 across the front and a pair of iQ1 in the rear. The current system sounds great, the upgrade will have to be a significant step up sonically in order to be worthwhile.
The fronts will be against a wall, so they will be either sealed or front-ported (I have always assumed that in order to get a quality 6 1/2" driver to crossover to a sub at 80Hz that it will be ported - some of this discussion has been otherwise, and i am open to reasons to go sealed).
The use is both HT and multi-channel SACD and DVD-A.
I do not have the skills to build my own speakers, but I have the grey matter and desire to explore requirements and come up with driver selection. I will have the speakers built by Jim Salk (Salk Sound) whose crossovers get designed by Dennis Murphy (Philharmonic Audio); the first project I did with the two of them turned into the WOW1 Mini Monitor for Salk Sound.
An externally hosted image should be here but it was not working when we last tested it.
As to budget, it is more determine what the upgrade will cost, then save to get it. I suspect the 5.0 will cost in the $3500 - $6000; largely dependent on final driver selection.
Seat to seat variations need to be small, and the same for seated versus standing. Crossover lobing might put restrictions on the speaker.
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