Found a reputable shop with a pair of freshly re-coned EVM15l for $90 a piece. I think I am just pull the trigger on them. Also, fired up the Mid/HF cabinets and all but 1 of the T35s work. Nice sounding but the crossover is not working correctly so I had to rig something up. Will start a new thread in multi area unless any takers for XO help.
So these cabs are the in listening room AKA basement with a box of fresh drivers nearby. Starting to think XO. Would like to keep this cost effective. Some work to be done on the tops, one tweeter blown and passive XO is not working. Anyone have some suggestions? I can take pics of XO components. The stuff is rather large and heavy so I assume it's decent and wonder if it can be repaired. Not perfectly knowledgeable in XO but managed to unhook things to test drivers at low levels and all but 1 tweeter is functional but if I reconnect to XO they are dead. OR maybe just go active and be done with it? Thoughts or direction gents? Thanks in advance.
Zwiller,
1) The crossovers consist of capacitors, resistors and coils. Continuity through the caps and coils can be tested with an ohm meter. The capacitors require a capacitance meter to actually determine if they still are the correct value (and an ESR meter to determine if their equivalent series resistance has risen too high), but you can test if they work or not with clip leads. Likely there are simply some cold solder joints to track down.
2) Costs more than fixing your passives, but ultimately DSP, if properly implemented, can sound better.
3) Clean the gap and replace the blown T35 diaphragm (properly aligned) or the passive crossover will not cross properly.
Art
Art,
Thanks. For some reason I get lost with passive XO circuits. I basically know the concepts but still not clicking. I have a decent meter with cap values so I should be able to check for that a continuity. Might heat all up with some fresh solder for good measure too. The Behringer analog rack XO any good? Will consider upgrading to DSP down the road. Fortunately, the reconing guy can do the T35. From what I can tell when I took it apart it is not blown, but I am a complete noob here.
Thanks. For some reason I get lost with passive XO circuits. I basically know the concepts but still not clicking. I have a decent meter with cap values so I should be able to check for that a continuity. Might heat all up with some fresh solder for good measure too. The Behringer analog rack XO any good? Will consider upgrading to DSP down the road. Fortunately, the reconing guy can do the T35. From what I can tell when I took it apart it is not blown, but I am a complete noob here.
1) I had one, it sounded OK but I had to add a heat sink on the main chip to keep it working on hot days in the sun.
2) The voice coil is either open or has continuity (it should read around 6 ohms DCR IIRC), if it has continuity it should work unless stuck in place. Soldering the tiny leads on a T35 can be a challenge, another place to look for cold solder joints.
Started a thread in multi-way about crossover help if anyone is interested. http://www.diyaudio.com/forums/multi-way/286268-kustom-mt15-gollehon-mr90-crossover-help.html
That would be OK for temporary use.
For lower tuning you should extend the port depth, rather than reducing the size, though you could do a bit of each considering the 15L's excursion.
The port location near the cabinet edge will probably result in a lower Fb than sims would suggest.
Right now the 1824's are the star of the show. They have a very nice sound and it has made me a fan of a horn system at home. Definitely the best setup I've owned/heard. I hear potential in the bass cabs but I think I need to get a low pass on them to do them justice but then goes the slippery slope of XO design. Would prefer a simple 1st order BW inductor?
After reading much about Khorns VOTT and other horn systems I can now attest to the dynamic/liveliness. Love it. Quite remarkable. Never heard of VOTT before these fell into my lap... It actually sounds like real instruments in my basement/home theatre. My wife even noticed and agrees. I am actually quite dumbfounded this gear was basically considered "junk". One man's trash I guess. The history of the gear is also a cool bonus.
All in all a great audio learning experience with room to grow. First is the low pass and 2nd will be upgrading the tweeters. Most likely APT200. Then maybe some port reduction.
After reading much about Khorns VOTT and other horn systems I can now attest to the dynamic/liveliness. Love it. Quite remarkable. Never heard of VOTT before these fell into my lap... It actually sounds like real instruments in my basement/home theatre. My wife even noticed and agrees. I am actually quite dumbfounded this gear was basically considered "junk". One man's trash I guess. The history of the gear is also a cool bonus.
All in all a great audio learning experience with room to grow. First is the low pass and 2nd will be upgrading the tweeters. Most likely APT200. Then maybe some port reduction.
Ordered some inductors and APT150. Hooked the APT150's up and do not like them at all. Blah. What did I expect for $25?! 
I was hoping for a bit more extension... Anyone think the EV ST350 are much better than the T35? I like the T35 but it seems a bit mild, so if the ST350 is improved then that might be a way to go.
I was hoping for a bit more extension... Anyone think the EV ST350 are much better than the T35? I like the T35 but it seems a bit mild, so if the ST350 is improved then that might be a way to go.
ST 350 probably won't be much (if any) improvement over the APT150, they are only a minor improvement to the T35.Ordered some inductors and APT150. Hooked the APT150's up and do not like them at all. Blah. What did I expect for $25?!
The APT150 would benefit from a bypass cap to bring the HF up to the mid level, without the bypass cap the top end is 5 dB down.
Zwiller,
Better in that you could eliminate the mid/high crossover point required when using the 1824 high mid drivers. Crossovers are the hardest thing to get right, especially right in the middle of your hearing's most sensitive range.
I have not heard the Selenium 220 driver, but there is nothing in the specs that would indicate it would be a step up in fidelity from the APT tweeters. I used the APT80 in monitors, sounded good, though had inconsistent response from unit to unit, same could be said of the EV T35.
I'd suspect the hard chines on the APT150 horn cause more diffraction effects than the smooth exponential APT80 flare, which also does not require as much HF boost (or mid cut) as the constant directivity APT150.
Art
When you say eliminate the crossover over point, do you mean forgo 3 way and go 2 way with 2" CD or literally, just remove it?
I think I agree with you on the APT150 horn. Removing it was a step up. A smaller horn also makes sense too as the lower end of the HF is quite strong IMO. Perhaps I was expecting something different from a "super tweeter"... I was actually worried it would be only sizzle and air...
I think I agree with you on the APT150 horn. Removing it was a step up. A smaller horn also makes sense too as the lower end of the HF is quite strong IMO. Perhaps I was expecting something different from a "super tweeter"... I was actually worried it would be only sizzle and air...
I meant using the Selenium titanium diaphragm driver you suggested above the 15" all the way out to 20kHz, rather than using a tweeter above the phenolic EV driver.
The APT150s definitely need a bypass cap to bring up the HF. They should also not be used below 3kHz or so (at least the manufacturer says so), even though they measure quite flat on-axis to 2kHz.
If used with a "normal" HP filter, they'd probably sound like crap. All shriek with no "top".
Not that they're perfect. See that BIG suckout @ 6kH? That's a DRIVER issue, and not caused by the horn. It was still present when I measured the driver alone. And that's why I opted to use different drivers for my design (I kept the horns
).