MunkeyQ
Super Member
Well, after gathering the parts for far too long, I've finally got a working speaker.
It's a sort of Econowave, using the Celestion CDX1-1745 (used in QSC HPR152i) on the conical HPR122i waveguide. Note to anyone else trying this combo - it's not a straight bolt-together build as unlike most waveguides, the holes are tapped since the 1425 bolts through from the other side. I drilled the threaded brass inserts out and had to use studs +nuts to attach the driver, after cutting away some bracing plastic fillets to get pliers in there to tighten the nuts.
It's biamped with a DBX Driverack, which makes playing around with crossover and EQ goodness a lot easier.
Since apparently this combination hasn't been used before (and I lack any measuring gear!), I'm having trouble dialing in the CD EQ. I'm basing it on the 1425/HPR122i here. However, it sounds very nasal with a harsh hump at about 4khz, making vocals sound unnatural and electric guitar harsh. Wonderful on bluegrass though! I've been fiddling for a couple of days with no luck, so I'm wondering if anyone here can offer anything. Oh yep, here's the datasheets for the CDX1-1425 and CDX1-1745.
I'm using it with a Beyma 8BR40 woofer, which plays nice up until about 2khz and gets seriously nasty after that. It's tameable with a high Q notch filter, but I'd like to keep it playing <2khz if possible. Otherwise, it's a very nice woofer in a medium sized sealed cabinet - lots of smooth bass, low Fs and oodles of linear excursion. Seems to be the same cast basket as many Beyma midranges...smaller motor though.
However, I've got a niggling feeling that the nasal-ness is due to the woofer's HF limitations. Would be nice to get rid of the harshness though.
If anyone's wondering why I didn't go for the conventional E'wave build, it's because Selenium parts are unobtainable in the UK, and JBL charge a fortune for the waveguide. £7 for the part, £45 each for shipping! Over $160 just for the base-level waveguides...that's 18sound money.
QSC are much more reasonable, although shipping is very slow. Screw-on drivers are also uncommon over here, but Celestion parts are plentiful. I understand the 1745 uses the same diaphragm as the 1731, albeit on a ceramic motor.
Here's a photo...note the woofer's in a rather rough cabinet currently, but when I have time it'll get a nicer one. It's also a bit on the small size.
It's a sort of Econowave, using the Celestion CDX1-1745 (used in QSC HPR152i) on the conical HPR122i waveguide. Note to anyone else trying this combo - it's not a straight bolt-together build as unlike most waveguides, the holes are tapped since the 1425 bolts through from the other side. I drilled the threaded brass inserts out and had to use studs +nuts to attach the driver, after cutting away some bracing plastic fillets to get pliers in there to tighten the nuts.
It's biamped with a DBX Driverack, which makes playing around with crossover and EQ goodness a lot easier.
Since apparently this combination hasn't been used before (and I lack any measuring gear!), I'm having trouble dialing in the CD EQ. I'm basing it on the 1425/HPR122i here. However, it sounds very nasal with a harsh hump at about 4khz, making vocals sound unnatural and electric guitar harsh. Wonderful on bluegrass though! I've been fiddling for a couple of days with no luck, so I'm wondering if anyone here can offer anything. Oh yep, here's the datasheets for the CDX1-1425 and CDX1-1745.
I'm using it with a Beyma 8BR40 woofer, which plays nice up until about 2khz and gets seriously nasty after that. It's tameable with a high Q notch filter, but I'd like to keep it playing <2khz if possible. Otherwise, it's a very nice woofer in a medium sized sealed cabinet - lots of smooth bass, low Fs and oodles of linear excursion. Seems to be the same cast basket as many Beyma midranges...smaller motor though.
However, I've got a niggling feeling that the nasal-ness is due to the woofer's HF limitations. Would be nice to get rid of the harshness though.
If anyone's wondering why I didn't go for the conventional E'wave build, it's because Selenium parts are unobtainable in the UK, and JBL charge a fortune for the waveguide. £7 for the part, £45 each for shipping! Over $160 just for the base-level waveguides...that's 18sound money.
QSC are much more reasonable, although shipping is very slow. Screw-on drivers are also uncommon over here, but Celestion parts are plentiful. I understand the 1745 uses the same diaphragm as the 1731, albeit on a ceramic motor.Here's a photo...note the woofer's in a rather rough cabinet currently, but when I have time it'll get a nicer one. It's also a bit on the small size.
