I got a pair of Polk T50 at the flee market for a song. I thought these might be interesting to improve. The have some blown tweeters and the single 6.5 driver is stiff in both and one has coil rub. I knew this when I got them and bought them for the enclosure. In my system I run the Yamaha NS10M for front mains. And while these sound awesome (more so the closer you get) i wanted more power capability and to be able to better keep up with my Sub Woofer setup (2 custom ported 15s driven with the Kenwood L09M>
I don't mind some wood work but I am trying to make this a project others could also do if my results turn out good. The cabinet is nice but these are quickly overpowered. After lots of poking around on Parts Express I settled on the Morel CAT 378 with 2 each tower Dayton .
Im not set in stone and still exploring how to best load and use these.
It also would not be much work to separate the tower with a panel in between the upper 2 6.5 locations. I could use on or both passive radiators by adding a hole in front or to one of the lower side panels. I could also go 3 way with a TMWPsvRad
What thought have you all on how to load these. I'm not trying to go crazy on money and want to go the best path as far as speaker placement topology. 3 way costs a lots more. I have no idea of the effect adding a second woofer in parallel would have with more power and just one passive radiator.
I don't mind some wood work but I am trying to make this a project others could also do if my results turn out good. The cabinet is nice but these are quickly overpowered. After lots of poking around on Parts Express I settled on the Morel CAT 378 with 2 each tower Dayton .
Im not set in stone and still exploring how to best load and use these.
It also would not be much work to separate the tower with a panel in between the upper 2 6.5 locations. I could use on or both passive radiators by adding a hole in front or to one of the lower side panels. I could also go 3 way with a TMWPsvRad
What thought have you all on how to load these. I'm not trying to go crazy on money and want to go the best path as far as speaker placement topology. 3 way costs a lots more. I have no idea of the effect adding a second woofer in parallel would have with more power and just one passive radiator.
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Looks like a good buy.
You've linked the Dayton DC160 Classic woofer, which is OK but honestly, not up to the sonic standard of the Morels. I use the Morels with the RS180P, and they're a great match, sound wise.
May I suggest you look at Paul Carmody's Classix 2.5s:
Classix 2.5 - undefinition
The use the DC160 and the Vifa BC25TG tweeter (about $20) in a 2.5 way design, which Paul's site explains well. If they sound as good as the Classix II, which I enjoy very much, they will be very good indeed.
The cabinet size should work OK, the baffle width is about the same and the volume looks roughly similar. Not sure about the dimensions of the driver holes, of course but the specs are readily available.
HTH
Geoff
You've linked the Dayton DC160 Classic woofer, which is OK but honestly, not up to the sonic standard of the Morels. I use the Morels with the RS180P, and they're a great match, sound wise.
May I suggest you look at Paul Carmody's Classix 2.5s:
Classix 2.5 - undefinition
The use the DC160 and the Vifa BC25TG tweeter (about $20) in a 2.5 way design, which Paul's site explains well. If they sound as good as the Classix II, which I enjoy very much, they will be very good indeed.
The cabinet size should work OK, the baffle width is about the same and the volume looks roughly similar. Not sure about the dimensions of the driver holes, of course but the specs are readily available.
HTH
Geoff
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T50 ugrades
Thank you for the information GEOFF I will have a look at your links. And this helps because I felt like the Woofer I chose was going to be a challenge to crossover, & the idea to have 2 was an effort to catch up with the output of the Morel. These Dayton woofers are some of the only drivers I found that would physically work in the existing cutouts.
Thank you for the information GEOFF I will have a look at your links. And this helps because I felt like the Woofer I chose was going to be a challenge to crossover, & the idea to have 2 was an effort to catch up with the output of the Morel. These Dayton woofers are some of the only drivers I found that would physically work in the existing cutouts.
Apart from the drivers physically fitting in the existing cut outs, you should also look at the centre to centre distances between the drivers, and compare them with the Classix 2.5: Paul's crossover would have taken those into account. Somebody with more expertise than I would have to advise you on what sort of variation in those measurements would be OK.
The VIFA is a little larger diameter than the Morel, so depending on the size of the cut out for the Polk tweeter, some surgery might be required.
The crossover has quite a few parts but should be easily put together. It has one more part than the Classix II and if an idiot like me can put that together, anyone can.
Geoff
The VIFA is a little larger diameter than the Morel, so depending on the size of the cut out for the Polk tweeter, some surgery might be required.
The crossover has quite a few parts but should be easily put together. It has one more part than the Classix II and if an idiot like me can put that together, anyone can.
Geoff
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That's a fine driver apparently: but if you use them, you'll have to work out a new crossover. If someone could do that for you, that's an option.
The VIFA is a nice tweeter, I own it and the CAT378 and while the VIFA isn't as resolving or can be driven as hard as the Morel, it's still good. With a proper crossover, it will sound better than the Morel with a lesser crossover.
The diameter of the Morel is 95mm, the VIFA 104mm, so it could fit with just a little surgery.
Geoff
The VIFA is a nice tweeter, I own it and the CAT378 and while the VIFA isn't as resolving or can be driven as hard as the Morel, it's still good. With a proper crossover, it will sound better than the Morel with a lesser crossover.
The diameter of the Morel is 95mm, the VIFA 104mm, so it could fit with just a little surgery.
Geoff
What about these drivers and I can reduce my cost significantly while still improving over the original drivers.?
Dayton Audio DC160-8 6-1/2" Classic Woofer
Morel MDT 29 1-1/8" Soft Dome Tweeter
And just 1 Woofer like the original design with all original distance placement intact. But I would have higher power handling with better components.
And I will buy the VATS3 and already have a nive measurement mic. Then I could play with the original crossover or make ,buy, a better one.
Dayton Audio DC160-8 6-1/2" Classic Woofer
Morel MDT 29 1-1/8" Soft Dome Tweeter
And just 1 Woofer like the original design with all original distance placement intact. But I would have higher power handling with better components.
And I will buy the VATS3 and already have a nive measurement mic. Then I could play with the original crossover or make ,buy, a better one.
I can't open the image, unfortunately. The XO frequency may be noted in the instruction manual or reviews,but you wouldn't really want to use the same XO with different drivers anyway..
I'm surprised no-one else has replied to your post, as I'm only a beginner at this stuff - but I've built five pairs of DIY speakers and used two of the drivers you're looking at. I've designed only one crossover which sounded OK but not great.
I think the other Morel will have the same quality mis-match issues as the CAT378; also, the DC160 is not a high output or high 'Xmax' woofer and I find it's relatively easy to get them to 'bottom out' at reasonable volume with certain music; if your room isn't too large, that might not be an issue. We use our Classix II in the garage/workshop.
For example, The Band's 'Up on Cripple Creek' has a really funky bass/drum pattern; unfortunately, it's also very taxing for the speakers.
Remember, all this is just IMHO and other people will have different suggestions for you.
Geoff
I'm surprised no-one else has replied to your post, as I'm only a beginner at this stuff - but I've built five pairs of DIY speakers and used two of the drivers you're looking at. I've designed only one crossover which sounded OK but not great.
I think the other Morel will have the same quality mis-match issues as the CAT378; also, the DC160 is not a high output or high 'Xmax' woofer and I find it's relatively easy to get them to 'bottom out' at reasonable volume with certain music; if your room isn't too large, that might not be an issue. We use our Classix II in the garage/workshop.
For example, The Band's 'Up on Cripple Creek' has a really funky bass/drum pattern; unfortunately, it's also very taxing for the speakers.
Remember, all this is just IMHO and other people will have different suggestions for you.
Geoff
I had a look at various websites and reviews of the Polks: it has a tweeter, one woofer, and two passive radiators. I originally thought it had two woofers, my mistake. Reviews noted some harshness in the treble when pushed, but then they aren't expensive speakers.
The XO is apparently a second order (i.e. a cap and coil on each driver, plus padding resistor on tweeter) but the XO frequency wasn't stated. The size of the driver cut outs and rebates wasn't given, apart from saying '6.5" woofer' and "1" tweeter.
I assume you've measured the cut outs and driver rebates in the Polks and then had an optic and the specs of the DC160 and Morels to see if they would fit without major mods to the cabinet? I still think they would be an odd couple but it's your decision of course: but you'll have to design the crossover, if you buy an 'off the shelf' one it won't work properly.
Additionally, and I should have mentioned this before, I don't know how well the DC160 (or any woofer, for that matter) would work with a passive radiator(s); Polk would have designed the speakers to get all the bits to work together.
Assuming you're going to use grilles, any handiwork will be covered up - you should see my Classix, the baffle is a real dog's breakfast but very well hidden!
Geoff
The XO is apparently a second order (i.e. a cap and coil on each driver, plus padding resistor on tweeter) but the XO frequency wasn't stated. The size of the driver cut outs and rebates wasn't given, apart from saying '6.5" woofer' and "1" tweeter.
I assume you've measured the cut outs and driver rebates in the Polks and then had an optic and the specs of the DC160 and Morels to see if they would fit without major mods to the cabinet? I still think they would be an odd couple but it's your decision of course: but you'll have to design the crossover, if you buy an 'off the shelf' one it won't work properly.
Additionally, and I should have mentioned this before, I don't know how well the DC160 (or any woofer, for that matter) would work with a passive radiator(s); Polk would have designed the speakers to get all the bits to work together.
Assuming you're going to use grilles, any handiwork will be covered up - you should see my Classix, the baffle is a real dog's breakfast but very well hidden!
Geoff
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I modeled the XO in Xsim, using a DC160-4 woofer, a CAT 378 tweeter (i.e. the parts being considered by the OP) and the parts values provided in the diagram.
I think the electrical XO point is about 1000Hz, which doesn't sound right - perhaps too low for the tweeter?
There's no Baffle Step Compensation, but perhaps the passive radiators take care of that - I don't know anything about how they work, I'm sorry.
I've tried to attach the Xsim shots, my apologies if that doesn't work properly. Please note that the sim is not measured, it just uses the 'official' driver graphs provided by the makers. The red is the combined response, the black is the tweeter and the brown is the DC160. Even allowing for the effects of in-situ measurement etc, I think the Polk must have used a much more efficient woofer!
This doesn't particularly mean much, except that a new crossover will be required if different drivers are used.
Geoff
I think the electrical XO point is about 1000Hz, which doesn't sound right - perhaps too low for the tweeter?
There's no Baffle Step Compensation, but perhaps the passive radiators take care of that - I don't know anything about how they work, I'm sorry.
I've tried to attach the Xsim shots, my apologies if that doesn't work properly. Please note that the sim is not measured, it just uses the 'official' driver graphs provided by the makers. The red is the combined response, the black is the tweeter and the brown is the DC160. Even allowing for the effects of in-situ measurement etc, I think the Polk must have used a much more efficient woofer!
This doesn't particularly mean much, except that a new crossover will be required if different drivers are used.
Geoff
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Yes indeed, that looks much better! I just simmed the way it was drawn, I should have thought it through more.
Electrical XO is about 2200 Hz, sim looks more realistic now. But it's only a sim, not measured and doesn't take the quality and sound of the drivers into account .
At least in the sim, the DC160 woofer has a nasty looking bump at about 2900 Hz which may be audible. Paul Carmody's Classix designs deal with that issue brilliantly.
Still not enough Baffle Step Compensation, but please see above comments on passive radiators.
Geoff
Electrical XO is about 2200 Hz, sim looks more realistic now. But it's only a sim, not measured and doesn't take the quality and sound of the drivers into account .
At least in the sim, the DC160 woofer has a nasty looking bump at about 2900 Hz which may be audible. Paul Carmody's Classix designs deal with that issue brilliantly.
Still not enough Baffle Step Compensation, but please see above comments on passive radiators.
Geoff
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Oh WOW thank you guys! So maybe with some fresh proper caps I can give that a spin as it is in the ballbark of my crossover range. that diagram Allen B is exactly my crossover. It seems this would be safe for me to try and then I can get some real measurements. I do plan to buy the VATs3 and I do have REW and a very nice measurement mic. Some capacitors would be cheap. Or if you have any suggestions for tweaking the caps I would start there. Im not going to use 2 woofers just 1 with the 2 passive radiators like the original design. ive already learned that these enclosures represent some challenges when it comes to what will physically fit. Thanks again guys!