Starting a new speaker design: unusual 4-way

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tcpip

tcpip

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After reading a lot on various forums, and thinking and talking a lot about it, I decided to kick off a new design, new and different for me in many ways. I'm sure I'll learn a lot from it.

Firstly, it's a 4-way. I've never done a 4-way design before. And since it'll be a passive crossover, it's going to make me stretch whatever little I know about crossover design and speaker measurements.

Secondly, it'll be lower order crossovers. I'm currently toying with the idea of 2nd order slopes. I may even try 1st order on some of the crossover points. 4-way design means three crossover points, so I have a lot of points to pick and choose from.

Thirdly, as a consequence of the shallow slopes, I'm choosing drivers by the smoothness of their SPL curves above all else. This means that I'm ignoring distortion behaviour and all other attributes of the drivers.

Fourthly, this will be the first time I'll experiment with stepped baffles. Let's see what the combination of multiple-way, shallow slopes and stepped baffles gives me.

Fifth, I am thinking of some weird enclosure experiments for the midrange drivers -- I'll make their chambers neither sealed nor open at the back. I'm thinking of trying wide-diameter PVC tubes on the rear wall of their chambers, like ducted ports, except that they'll be fairly tightly filled with Polyfill type fibre to absorb the back wave. The aim is to neither reflect the rear wave, nor allow it to emerge at the rear -- just absorb it. Will it work? Who the hell knows? But it'll be great if it does work.

The trigger for a lot of this was from the writings of Troels Gravesen. Many others have written about the benefits of multi-way designs -- many designers seem to consider a 3-way as the minimum for decent performance. I've done a 3-way, though active, with the Darbari, so I decided I'll push a bit further this time, hence 4-way. And I'm intrigued by Troels Gravesen's comments about physical time alignment -- he seems to be doing this for pretty much all his designs.

Since I am very unsure of my own capabilities to design such a beast, I decided to keep costs low, therefore chose inexpensive drivers. After searching through Madisound, Parts Express and other sites, I decided to go with inexpensive options closer to home -- I picked SB Acoustics from DIYAudioParts for 3 out of the 4 drivers.

The main aim for driver selection was "well behaved" drivers -- drivers whose SPL curves are so benign that I can afford to let them play with wide overlap from one another without struggling to cut out cone-breakup resonances or other unevennesses. Therefore, paper or poly cone drivers seem to be the only viable drivers.

When building a 4-way design, the natural driver sizes seem to fall into the following structure:
  • a dome tweeter: one inch or smaller, since I can afford to cross over to it even as high as 3KHz
  • a 4" or 5" upper mid
  • an 8" lower mid
  • a 12" or 15" woofer for the bottom 3 octaves or so
And then imagine all of them playing together like a merry little chorus group, with massive overlaps across their borders. So different from what I've been doing all this time. It's safe to say that with four such narrow pass-bands and shallow slopes, you can choose any frequency and you'll almost certainly hear the output of, not one or two, but three drivers playing in chorus. Will it be harmony or cacophony? Who knows?

It's really hard to find midrange or midbass units which can take shallow slopes at their upper end (i.e. their low-pass filters) and still sound decent. Most hard cones, which are good at reproducing accuracy and detail, have severe cone break-up at their upper ends, which means their crossover slopes will need to be at least 4th order to let me suppress their break-up regions by at least 50 dB or more. For metal-cone drivers, 70 dB suppression is preferable.

With these criteria, the drivers which fit the bill most easily are the full-range drivers. The better full range drivers have a long, flattish SPL curve which will behave well with shallow slopes because they have no ugly SPL peaks even 3 octaves beyond their upper crossover point. I found the following drivers pretty suitable:

Keeping in mind the costs and ease of procurement, I chose
Haven't chosen the bottom driver yet. Will look for some inexpensive 12" or 15" driver. Am tempted to look at Dayton Classic or Designer Series drivers from Parts Express. It will be really super if I can find something which will go low in a sealed box without equalisation. By "going low", I mean an F10 (10dB below the baseline of the SPL curve) of 20 Hz. If I can't find anything like that, there are always bass reflex options. The Dayton Designer Series 12" woofer for instance seems to give me an F10 of 28Hz in a 60-litre box and a very nice 22Hz in a vented box 70 litres in size with a 2" port 7.7" long.

The crossover points will be
  • between 150-300Hz for woofer to lower mid
  • between 300-700 for lower mid to upper mid
  • between 2.5KHz and 3.5KHz for upper mid to tweeter

I have no idea how it'll turn out. Watch this space, wish me luck, and come over to my place in New Bombay for a listen when it's all done. :D
 
Last edited:
tcpip said:
After reading a lot on various forums, and thinking and talking a lot about it, I decided to kick off a new design, new and different for me in many ways. I'm sure I'll learn a lot from it.

Firstly, it's a 4-way. I've never done a 4-way design before. And since it'll be a passive crossover, it's going to make me stretch whatever little I know about crossover design and speaker measurements.

Secondly, it'll be lower order crossovers. I'm currently toying with the idea of 2nd order slopes. I may even try 1st order on some of the crossover points. 4-way design means three crossover points, so I have a lot of points to pick and choose from.

Thirdly, as a consequence of the shallow slopes, I'm choosing drivers by the smoothness of their SPL curves above all else. This means that I'm ignoring distortion behaviour and all other attributes of the drivers.

Fourthly, this will be the first time I'll experiment with stepped baffles. Let's see what the combination of multiple-way, shallow slopes and stepped baffles gives me.

Fifth, I am thinking of some weird enclosure experiments for the midrange drivers -- I'll make their chambers neither sealed nor open at the back. I'm thinking of trying wide-diameter PVC tubes on the rear wall of their chambers, like ducted ports, except that they'll be fairly tightly filled with Polyfill type fibre to absorb the back wave. The aim is to neither reflect the rear wave, nor allow it to emerge at the rear -- just absorb it. Will it work? Who the hell knows? But it'll be great if it does work.

The trigger for a lot of this was from the writings of Troels Gravesen. Many others have written about the benefits of multi-way designs -- many designers seem to consider a 3-way as the minimum for decent performance. I've done a 3-way, though active, with the Darbari, so I decided I'll push a bit further this time, hence 4-way. And I'm intrigued by Troels Gravesen's comments about physical time alignment -- he seems to be doing this for pretty much all his designs.

Since I am very unsure of my own capabilities to design such a beast, I decided to keep costs low, therefore chose inexpensive drivers. After searching through Madisound, Parts Express and other sites, I decided to go with inexpensive options closer to home -- I picked SB Acoustics from DIYAudioParts for 3 out of the 4 drivers.

The main aim for driver selection was "well behaved" drivers -- drivers whose SPL curves are so benign that I can afford to let them play with wide overlap from one another without struggling to cut out cone-breakup resonances or other unevennesses. Therefore, paper or poly cone drivers seem to be the only viable drivers.

When building a 4-way design, the natural driver sizes seem to fall into the following structure:
  • a dome tweeter: one inch or smaller, since I can afford to cross over to it even as high as 3KHz
  • a 4" or 5" upper mid
  • an 8" lower mid
  • a 12" or 15" woofer for the bottom 3 octaves or so
And then imagine all of them playing together like a merry little chorus group, with massive overlaps across their borders. So different from what I've been doing all this time. It's safe to say that with four such narrow pass-bands and shallow slopes, you can choose any frequency and you'll almost certainly hear the output of, not one or two, but three drivers playing in chorus. Will it be harmony or cacophony? Who knows?

It's really hard to find midrange or midbass units which can take shallow slopes at their upper end (i.e. their low-pass filters) and still sound decent. Most hard cones, which are good at reproducing accuracy and detail, have severe cone break-up at their upper ends, which means their crossover slopes will need to be at least 4th order to let me suppress their break-up regions by at least 50 dB or more. For metal-cone drivers, 70 dB suppression is preferable.

With these criteria, the drivers which fit the bill most easily are the full-range drivers. The better full range drivers have a long, flattish SPL curve which will behave well with shallow slopes because they have no ugly SPL peaks even 3 octaves beyond their upper crossover point. I found the following drivers pretty suitable:

Keeping in mind the costs and ease of procurement, I chose
Haven't chosen the bottom driver yet. Will look for some inexpensive 12" or 15" driver. Am tempted to look at Dayton Classic or Designer Series drivers from Parts Express. It will be really super if I can find something which will go low in a sealed box without equalisation. By "going low", I mean an F10 (10dB below the baseline of the SPL curve) of 20 Hz. If I can't find anything like that, there are always bass reflex options. The Dayton Designer Series 12" woofer for instance seems to give me an F10 of 28Hz in a 60-litre box and a very nice 22Hz in a vented box 70 litres in size with a 2" port 7.7" long.

The crossover points will be
  • between 150-300Hz for woofer to lower mid
  • between 300-700 for lower mid to upper mid
  • between 2.5KHz and 3.5KHz for upper mid to tweeter

I have no idea how it'll turn out. Watch this space, wish me luck, and come over to my place in New Bombay for a listen when it's all done. :D
Click to expand...


This is a great news for us .

For the tweeter the ring dome SB-Acoustics-SB29RDC-C000-4 is also a great option it will take it to the next level for a few dollars more .

All the best .
 
somakmaitra said:
For the tweeter the ring dome SB-Acoustics-SB29RDC-C000-4 is also a great option it will take it to the next level for a few dollars more
Click to expand...
I wanted to do this build with budget drivers, so I don't want to get into costlier drivers. Once I find the finished system worth the effort, all the SB Satori midbass drivers become candidates too, for a more "high end" build. The MR13 midrange for instance should be a great upper mid...
 
This thread will be on my watchlist... Best of Luck Bro... Do keep on Sharing the progress as well as construction Photos :)
 
Toys have arrived!

I think I design speakers so that I can get to play with new toys. :(

The box came in: excellent packing:
ilx4zl.jpg


I took out the tweeter. Metal flange, excellent build quality and finish. My favourite Seas TDFC has a plastic front plate and feels flimsier.
2im3pzb.jpg


9t1m5l.jpg


Then came the 5" upper-mid driver. Once again, absolutely outstanding build, the polycarbonate basket feels almost like metal. These are the SB13PFC25 square frame model, not the SB13PFCR25 round frame models I had ordered. The supplier ran out of those when I placed my order, so they sent me these. I'm happy -- they are almost identical in performance and the looks will match the 8" drivers.
2hz02kx.jpg


15psufc.jpg


Then came the 8" driver, bigger brother of the 5":
21owuvs.jpg


Note how this one has eight mounting screw holes.

Placing them side by side gives you an idea of relative sizes:
20hv98g.jpg


25kprwz.jpg


Finally, the superb Jantzen binding posts:
2sbkfhs.jpg


2af0235.jpg


These are superbly finished. I was a great fan of Dayton Audio binding posts and mounting plates of a similar design, but these are more, well, "European" in design. And they're available in India for a reasonable price.

I have still to decide on the woofer driver. It'll be a 12" or 15".

And one of the Troels Gravesen projects which is inspiring me to design this system is Troels Gravesen's SBA 941, where the "941", I presume, refers to a 9.5" woofer, a 4" mid, and a 1" dome tweeter. He's used far more expensive drivers than what I'm doing, but his crossover design and thoughts about it are a big guide for my own thinking.

I'm toying with the idea of crossover points at 200Hz, 700Hz, and something like 2.5KHz or 3KHz. I'm thinking of using 1st order wherever possible, like the upper-mid-to-tweeter, and using notch filters wherever cone breakup can't be ignored with my shallow crossover slopes. Let's see how it goes.

I may have a problem with enclosure height. If I keep the tweeter at about 40", which is about right for my home, and I put the other three drivers below the tweeter, then I will get into trouble -- there will only be about 20" of height for me to fit my 12" or 15" woofer. Therefore, I may sequence the drivers as UM-T-LM-W instead of the textbook design of T-UM-LM-W. This will allow me to get more height for the "W" while keeping the "T" at ear height of about 40". I'll make one enclosure for the woofer, which will also house the crossover. I'll place a second enclosure on top of it to mount the three remaining drivers.

Let's see. Let's see.
 
Last edited:
I just looked closely at the drivers again to see how far below the front baffle their (presumed) acoustic centres would be. I came up with:
  • tweeter: 3mm
  • upper mid: 20mm
  • lower mid: 25mm

I am sure I can afford to ignore the woofer's alignment, considering that it will only work at very long wavelengths.

The tweeter was a bit of a surprise. I had originally thought that I could assume its acoustic centre would be aligned with the front baffle. But I realised that only with the tweeter, I would be countersinking it, therefore I would be pushing the front plate down into the baffle. And in this particular tweeter, there is a very tiny waveguide-like depression around the dome, and the dome is inset a tiny bit. So, I'm assuming that the acoustic centre is 3mm below the front baffle.

With the other two drivers, I'll be surface mounting them, no recess, since I don't know how to do a recess neatly for their odd shapes. Therefore I measured the acoustic centres as the point where the dust cap meets the cone, and measured (approximately) how far it is from the rear surface of their flange.
 
Tarun, would a down firing woofer configuration be an option to make
the cabinet design easier? like this one - (I know squat about speaker design, so ...)

www.stereophile.com

NEAT Acoustics Iota Alpha loudspeaker

Reviewers of high-fidelity gear are a trend-sniffing, topology-bandying bunch. When four of our kin gathered last November over lunch, during the 2016 New York Audio Show, the high-end chatter flew fast and furious. "Did you hear those mother-rocking big horns on the seventh floor?" "Nah, man...
www.stereophile.com www.stereophile.com
 
quad said:
Tarun, would a down firing woofer configuration be an option to make
the cabinet design easier? like this one - (I know squat about speaker design, so ...)

www.stereophile.com

NEAT Acoustics Iota Alpha loudspeaker

Reviewers of high-fidelity gear are a trend-sniffing, topology-bandying bunch. When four of our kin gathered last November over lunch, during the 2016 New York Audio Show, the high-end chatter flew fast and furious. "Did you hear those mother-rocking big horns on the seventh floor?" "Nah, man...
www.stereophile.com www.stereophile.com
Click to expand...
Down firing woofers are common, specially for subs. But if you want a bit of the lower mids to also be reproduced by your woofer, I think it's best to point the driver at the listener, so that he gets the immediacy of directly radiated sound. So, for frequencies till about 100Hz, down-firing is perfectly fine.

Another compromise option many designs take is to do side-firing woofers. I have the same problem even with that.
 
I also have another recommendation .. How about the Eaton 10-12 inch drivers ? The seas should be good for orchestra or instrumental type of music , but the Eaton might be a much more suitable candidate for an all round performer ..
 
yugaaa said:
I also have another recommendation .. How about the Eaton 10-12 inch drivers ? The seas should be good for orchestra or instrumental type of music , but the Eaton might be a much more suitable candidate for an all round performer ..
Click to expand...
Can you share some more details? Why do you think so? Plus, which Eton range exactly are you referring to? The Symphony II, the Arcosia, and the Orchestra ranges are totally different from each other.

Plus, my aim here is to build a sort of concept-proving speakers to test half a dozen new ideas. I don't want too expensive drivers. Will Eton drivers fit?

I struggled with woofer choices, and finally chose one.

Since I've decided to almost use this thread as a journal to log my meanderings and doubts, let me share what I went through.

I was thinking that I'll use this for the bottom 3-4 octaves (i.e till 125 or 250Hz), and I wasn't really insisting on low distortion or high power, both of which require more expensive drivers. However, what I was definitely looking for was a smooth SPL curve with little or no cone breakup. And I wanted inexpensive drivers, as explained earlier. If possible, it would be great to not have to import anything. And since the next up in the sequence is an 8", I didn't want a 10" here -- I wanted at least a 12". Therefore, I was looking for 12" or 15" drivers.

In the Indian options, DIYAudioParts had excellent SB woofers of 12" size. Expensive. I kept them aside. But their T/S parameters were nice -- their Qts was in the right range and the Fs was low -- in the region of 20Hz. They would have been perfect if they weren't so expensive. DIYAudioCart (yes, they're alive) had the following:
  • Peerless FSL 12". Right price, right size, good brand. Wrong T/S parameters. The Qts was fine; the Fs was too high. 66Hz. What the hell do I do with 66Hz? These are pro drivers. They don't always have low Fs -- in fact, they rarely have low Fs. They have (i) high power handling, and (ii) high sensitivity. What you are expected to do with them is drive them hard using electronic equalisation -- a bass boost in your mixer or preamp. But I wanted a fully passive speaker, where it should sound good out of the box without equalisation, and reach low. How will a 66Hz Fs speaker reach 25Hz without equalisation? I gave up, feeling depressed. The sensitivity was good enough to drive through SET valve amps. :(
  • Eminence Alpa 15A. Great price, right size, good brand. But look at the T/S parameters. The Qts is 1.26! This means there will be a loud peak in the bass response even in open air. In a box, the peak will be louder. What do I do with a peaking, obviously boomy driver? Once again, if I was equalising, it would be no problem at all. But I couldn't use it for this one. Sensitivity was an excellent 97 dB/W/m. Had to let it go.
  • Peerless NE series 12" woofer, them with the Neo magnets and sexy baskets. Good spec, good looks, good brand. But price was too high. Again, had to let it go. If I had such budgets, I'd buy the SB Acoustics 12" any day -- I don't see any reason to believe the SB woofers would be worse for my requirements.
Looked at the Electrocarts.in catalogue too, but couldn't find anything different which hadn't already been seen elsewhere.

Looked overseas. I had shortlisted the Dayton Classic 12" and 15" drivers, and Designer Series 12" driver. Of these, the Classic 12" was the cheapest, had the flimsiest construction, but had good T/S spec, good enough for me to get my job done. So, after checking shipping costs and other stuff, ordered the Classic 12". The price of the two woofers was $82, and including shipping, Customs, duties and taxes, they would be delivered to me for $208, all inclusive. That's less than the price of a single SB Acoustics woofer. And there is no Customs headache -- Parts Express has an Economy Int'l shipping option which takes some 2 weeks to deliver, but includes Customs duties and local delivery in their fees. So, I'll just sit back and wait.

One nice thing about the old traditional Classic 12" and 15" is their smooth SPL curves. One definitely does not need to think of anything more than 2nd order with them, and maybe 1st order will work too, if I cross over low enough.

I'm relieved. The last driver has been locked in. Now to design the cabinets.





And in keeping with my habit of naming my speaker designs after Hindustani classical ragas, I've decided to name this the Barwa.

I tried modelling the woofer. The Unibox model for the woofer enclosure is here as a ZIP file. Inside is just one Excel spreadsheet.

(For those who haven't used Unibox, it's just a spreadsheet. You need a recent version of MS Excel to open it, and you need the Analytics Toolpack enabled in your MS Excel. No other software needed.)

One of the reasons I want to post details of my design process here is so that at least some of you get the confidence to use tools and do design on your own in an engg way. It's pretty pointless me posting all these details of my journey if we can't grow more designers. I see a lot of DIY energy in this forum, and people take huge amount of trouble to build lovely objects. I rarely see anyone using the design tools needed to do a systematic design. I want to see that changing. Imagine what we will get once we mate proper design methods with the superb build processes you guys use. The guys here who do electronic design (amps and stuff) already are following very thorough design processes and using powerful tools and software, because without that, there's no way to design any PCB these days. But the speaker building members are often just fitting drivers on baffles and listening to the sound. I really hope this improves. This is the 21st century, and all you need is ARTA, VituixCAD, and Unibox, and you're a pro.

The model for a closed box (sealed enclosure) gave me this:
210nmfb.png

In Unibox, anything you see in blue has to be entered by the designer, and anything in red is calculated by the program.

As you can see on the left, this is a 74-litre box, which gives a gradual rolloff for the bass response. A smaller box would give a tighter curve and slightly steeper "knee". A roll-off like the one above (with a Qtc of about 0.55 to 0.6) apparently more closely reflects how room effects influence the bass. In other words, as the frequency rolls off gradually here, the room effects gradually become stronger in the same proportion, giving us a final result which is close to "flat". Needless to say, this is a simplistic approximation -- the results in different rooms will be different. But the key takeaway is that a shallow, smooth slope like this is apparently not as bad as it looks in the graph -- in reality the bass will extend more at the low end.

It is also believed that with such smooth roll-offs and shallow slopes, the realistic, in-room bass extension is not F3 or F6 but F10. If we see where the curve is 10dB down from the flat portion, we see that it is somewhere between 27-28Hz. So, some designers will say that the in-room bass extension of this speaker will be as low as 27 Hz.

If you think 74 litres is too big, you can go for a slightly tighter "knee" and a Qtc of 0.7, and you can shrink the box size to just 43 litres, as shown in the lines at the top left of the screenshot.

The model for the bass reflex box gave me this:
2rm1ik9.png

Here, we are modelling the box at 100 litres, with a single ducted port of 10cm diameter. If we do this, we get a port length of almost 40cm. Reducing the port diameter will immediately reduce the port length.

Here, you can see that the F10 has moved even lower than the sealed enclosure model, and we are at about 20Hz with this box, because of the effect of the port. So, we feel happy that this gives us even deeper bass than earlier.

Unibox gives us a convenient way to see the vented box and closed box curves in one graph, for easy comparison:
2hns8y8.gif

Ignore the bright blue (bandpass design) and the very light greenish-blue with the wriggles (the passive radiator design) because they have not been configured with any meaningful data. Unibox supports these four types of boxes, but I usually work with just vented or sealed.

The green line is the vented (bass reflex) response and the purple-blue line is the sealed enclosure. We can see that in the critical lowest two octaves, the bass reflex response is 5-6dB louder than the sealed enclosure, so we feel that this is great, and we should go with a bass reflex.

But drilling down into the details of the sealed and bass reflex models, we get the following discouraging insight:
33y2fky.gif

and
3142ovr.gif

These two graphs are in the detailed section of the Unibox screens. In each graph, the red line shows how much output this driver can actually reproduce, given its Xmax. In other words, the real output this driver can generate at full power is the portion below the red line only. Above this line, it is limited by the distance its cone can move. Feeding more power to it will make the cone move into non-linear behaviour and may even damage the driver.

Once I saw this red line, I realised that I will get roughly the same output from the driver whether I use the sealed or bass reflex enclosure, at high volumes. For both cases, the red line tells me that this driver cannot output more than 90dB at about 25Hz. It cannot output more than about 87dB at 20Hz. And so on. So, at low volumes, say 10dB lower than max volume, this driver will be able to deliver deep bass as per its respective graph (sealed or bass reflex), but at high volumes, its Xmax will limit its output.

This is a sanity check, and teaches us why generating clean, deep bass with that bass slam we all love needs lots of driver surface area. If I use a set of four drivers on each side, instead of just one, the red line will shift up by 6dB, and I'll be able to push much more power through the drivers without hitting their Xmax, thus producing loud and deep bass. But currently, with one driver per side, I will generate either loud bass at 110dB, or deep bass at 20-25Hz.

Anyway, I'll live with it. After all, there will be two channels, left and right, so the two will usually add up and give me 3dB more output. Plus, I play at fairly "domestic" volumes anyway.

How do the pro rigs, the discos, do their deep bass? Answer: they have different drivers which have larger surface area (15" and 18" are common), and often also have larger Xmax. And then they drive these drivers with hundreds of watts of amp power, to make the cone move half an inch either way. (12mm Xmax on either side is not unusual for those large pro bass kickers.)

One of the options open to me is to build a 100 litre box. This, if sealed, will give me an overdamped box with relatively less bass output volume, but that output will be very clean, and will be the opposite of "boomy". The cone will vibrate exactly as much as the signal drives it, and will not oscillate like a pendulum on its own (which causes the boomy bass which disco dancers love so much, but is opposite of high fidelity). If I add a vent of 10cm diameter and 40cm length, it will give me the bass reflex enclosure the model above shows. I can create two back panels, one with just flat plywood and the other with the ducted port in its middle. I can switch between these two, and see what I like more. That's what DIY let's me do. :) (Yes, I know, stuffing socks into the port is a well-tried option, but then the commercial speaker designer never designs their boxes large enough to give you good, overdamped sealed-box bass.) Some of the explanations here may be interesting.


In this design, I can't stop by just modelling the woofer. I will also have to model the box response of the lower-mid driver, which, at 8", is fairly large, and may need a decent sized box to behave in a predictable way. It will get a sealed box, and I will try to give it a box size such that it will give me a rolloff with a Qtc of 0.6 to 0.7. I can then factor it into the crossover design as part of its acoustic rolloff. The one thing I need to ensure is that I don't give it too small a box, because at a Qtc above 0.8 or so, there will be a peak in its response which will just mess up the overall speaker SPL.
 
Yes, a 3-way plus a sub is a natural config. I just want to see what happens if I build this to be totally passive. I'll keep the back panel of the woofer enclosure removable, so that I can simply remove it, put in a new one with amps and active setup if I want.
 
tcpip said:
Yes, a 3-way plus a sub is a natural config. I just want to see what happens if I build this to be totally passive. I'll keep the back panel of the woofer enclosure removable, so that I can simply remove it, put in a new one with amps and active setup if I want.
Click to expand...
Thats great but you amp requirement will be huge which will also have a cost impact since the lower priced woofer normally have low efficiency.
 
somakmaitra said:
Thats great but you amp requirement will be huge which will also have a cost impact since the lower priced woofer normally have low efficiency.
Click to expand...
Well, one rarely gets to see drivers less efficient than 84 dB these days, and an 84 dB driver can be driven beyond 100 dB SPL with 64W RMS. This means any solid state amp which can generate clean peaks of 60W+ is adequate for home use with almost any speaker.

The woofer I've chosen is rated at 90dB, so even a T-amp should suffice. And anyway, I'm not worrying about peak SPLs about this project. Let me see how the crossover turns out first and how it sounds.
 
tcpip said:
Well, one rarely gets to see drivers less efficient than 84 dB these days, and an 84 dB driver can be driven beyond 100 dB SPL with 64W RMS. This means any solid state amp which can generate clean peaks of 60W+ is adequate for home use with almost any speaker.

The woofer I've chosen is rated at 90dB, so even a T-amp should suffice. And anyway, I'm not worrying about peak SPLs about this project. Let me see how the crossover turns out first and how it sounds.
Click to expand...
Thats great you are going with Dayton 12 inch.
 
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