Ah, squeak deeper than the pth. I bet there is a big zpeak maybe 1.4khz. So it doesn’t really load much below that, yet jbl does and eq’s it.
Not sure how you define loading. I look at from the view of where the roll off starts. Attached are the frequency response and the impedance plots for both using the same large format 4" driver. Either one of them make an easy 800Hz crossover point and both can do well with a passive network to flatten out the response. As I see it both are very similar look at the impedance plots.
Rob🙂
Rob🙂
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ah, the pt-1 is 4.3" deep, so all 3, about the same depth.
I'm looking at the initial zpeak @ 1,500hz.
I was thinking that's where loading falls off, and where response would start falling, but it doesn't................
thanks for the graphs
I'm looking at the initial zpeak @ 1,500hz.
I was thinking that's where loading falls off, and where response would start falling, but it doesn't................
thanks for the graphs
If you like to have as close as possible to an M2 for the poors then the JBL 708 studio monitor would be a good starting point to copy.
2408H-2 with suitable waveguide and from JBL studiomonitor 708 8" drives 728G.
728G is 325$.
2408H-2 is 58.99$
The passive 708i is 1500$ and the active 708p is 1999$
2408H-2 with suitable waveguide and from JBL studiomonitor 708 8" drives 728G.
728G is 325$.
2408H-2 is 58.99$
The passive 708i is 1500$ and the active 708p is 1999$
No a M2 clone can definitely not be built with these but a decent speaker should be possible.
There are two things that should be kept in mind: You need to design a crossover thant can deal with the drooping frequency response of the horn/driver combination. And your woofer is 16 Ohms which means that you need a higher drive voltage compared to using an 8 Ohms one.
Regards
Charles
I don't really think that the H (8ohm) or J (16ohm) actually are so far from each other when driven by the same amp. The driver is sensitive 97db/1W so for home listening or even at (small) party level you get by with a 50W D class amp. I have used Hifimediy boards.
I use 2-time Hifimediy T1x4 so I have 8 channels. That's 62USD each so no waist if and when I want to upgrade.
But of course, if you want to play loud then you need much more. The best amp modules are today Hypex NC400 or some of their UcD amps.
Here is Hypex NC400 review and here as comparison Crown XLS 1502
I also think that EQ and XO such a setup (or any setup) with passive components will not give much room to find the best solution. So the far easiest way to do it is to use minDSP digtal filters. A good starting point is the 2x4HD (works also as premap) or if you are on a budget the plain 2x4HD 95USD.
There are many questions and good answers but only by doing will you know and learn. So build the box and get some sound from your setup. You will learn and you will get help with the next steps to take.
Se my picture. I hade these old KEF105 speakers. Took the base from them and put the horn on top. That was not difficult to do but I had the parts laying around for a year before I realized I can use them together.
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In that case, consider a 14" waveguide like this : B-52 PHRN-1014 1" Horn 10" x 14" Bolt-On
Along with a 15" or a 12" woofer of your choice
And a nice ring radiator compression driver
Here's an more obtainable approach:
Waveguide: DIY Sound Group SEOS8
Tweeter: ScanSpeak ring radiator
Woofer: B&C 8BG51
Crossover amp: minIDSP PWR-250
Direct radiating ring rather than CD, and SEOS contour rather than ICW (which you can't buy anyway in this size) but that sounds like a recipe for a nice high power standmount.
If I'm not mistaken, you're the only person in this thread who actually has a JBL 708.
How do you like it?
How do you like it?
I would go with a PTH 1010 with a suitable driver and either a 12 or 15 under with a possible provisions for a sub @80Hz depending on use HT vs Stereo. Subs never hurt the mains and the M2 has sub designed to be used with it if required.
Rob🙂
I’ll put it this way: I read DIYA out of curiosity now, not for inspiration. The only thing they lack is cabinet finishing.
I like 705s even better...
I’m surprised you haven’t picked up a pair of one of them yet.
if i purchase the jbl 4367 all parts from speaker exchange site so how close my diy 4367 is to jbl original 4367 speaker in sound quality?