Hi all,
I hope everyone had a nice Thanksgiving.
A while back, I picked up a pair of vintage early 1990s Radian 12" coax drivers #5012, no crossovers.
AFAIK they have the 450 compression drivers, 1" aluminum, same as many other Radian coaxes from 8" to 12".
For testing, I mounted them in 2.8 cf ported enclosures (some of you may recognize what they were...).
So all day yesterday, I was messing around with different different inductors, caps, and resistors using many alligator clips.
I felt like this morning I got 'in the ball park' and hardwired everything, as to eliminate the alligator clips that definitely hurt sq.
This is what I've arrived at so far, it sounds really good, but I'm sure it's not perfect yet, so I wanted you guys to look over it:
Continued in next post...
I hope everyone had a nice Thanksgiving.
A while back, I picked up a pair of vintage early 1990s Radian 12" coax drivers #5012, no crossovers.
AFAIK they have the 450 compression drivers, 1" aluminum, same as many other Radian coaxes from 8" to 12".
For testing, I mounted them in 2.8 cf ported enclosures (some of you may recognize what they were...).
So all day yesterday, I was messing around with different different inductors, caps, and resistors using many alligator clips.
I felt like this morning I got 'in the ball park' and hardwired everything, as to eliminate the alligator clips that definitely hurt sq.
This is what I've arrived at so far, it sounds really good, but I'm sure it's not perfect yet, so I wanted you guys to look over it:
Continued in next post...
No matter what I did, I couldn't get the HF to be smooth without the 20 Ohm parallel resistor as impedance correction.
As soon as I added that to the equation, it was really nice.
I was trying to keep the crossover as simple as possible.
Is that bad? Or is it acceptable?
To describe the sound right now:
Bass is great, dynamic and smooth.
Mids are full, possibly slightly forward but not shouty.
Treble is smooth, seems to gently roll off. It's not bright, but it's got some shimmer and sparkle if it's in the recording.
I'm going through all my usual reference cds and listening to a variety of different genres.
I had an additional 2.2 uf cap added to the 3.3 uf main high pass cap for most of the day. With that added, the mids are a little too much, so I was going to try maybe a 1.0 uf cap added, but with just the 3.3 uf it does sound nice.
As soon as I added that to the equation, it was really nice.
I was trying to keep the crossover as simple as possible.
Is that bad? Or is it acceptable?
To describe the sound right now:
Bass is great, dynamic and smooth.
Mids are full, possibly slightly forward but not shouty.
Treble is smooth, seems to gently roll off. It's not bright, but it's got some shimmer and sparkle if it's in the recording.
I'm going through all my usual reference cds and listening to a variety of different genres.
I had an additional 2.2 uf cap added to the 3.3 uf main high pass cap for most of the day. With that added, the mids are a little too much, so I was going to try maybe a 1.0 uf cap added, but with just the 3.3 uf it does sound nice.
Since hardwiring the xo, the imaging really improved. Center image is great now, soundstage is actually vast and well extends past the speakers, with great depth.
The sound overall is big and open, bass is dynamic and punchy. Live music sounds incredible, clapping sounds real and not like frying bacon.
To say that the speakers sound better than what originally came in these cabs would be an understatement... haha
My main concern is whether or not it's bad for the amp to have that parallel resistor on the HF. Adding that was really a game changer for the better.
Right now I'm less concerned with the bass, although it already sounds really good, bc I'm only in a small 10 x 16' room, and the test cab port tuning might not be ideal.
Unfortunately I don't have any measuring tools, I'm doing everything by ear.
Sorry for the long read! If anyone has anything to chime in, I'd appreciate it.
Is there anything very wrong with the xo that could be dangerous?
Thanks!
The sound overall is big and open, bass is dynamic and punchy. Live music sounds incredible, clapping sounds real and not like frying bacon.
To say that the speakers sound better than what originally came in these cabs would be an understatement... haha
My main concern is whether or not it's bad for the amp to have that parallel resistor on the HF. Adding that was really a game changer for the better.
Right now I'm less concerned with the bass, although it already sounds really good, bc I'm only in a small 10 x 16' room, and the test cab port tuning might not be ideal.
Unfortunately I don't have any measuring tools, I'm doing everything by ear.
Sorry for the long read! If anyone has anything to chime in, I'd appreciate it.
Is there anything very wrong with the xo that could be dangerous?
Thanks!
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R1 at 10 ohms ensures that the amplifier will not 'see' less than 10 ohms from the tweeter circuit. As long as the signal has to go through R!, the impedance should not go below 10 ohms from the tweeter circuit. So all should be fine.
I'll be interested in your final circuit.
I'll be interested in your final circuit.
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Thank you all for chiming in. I will continue listening and try small tweaks, as well as moving the speakers into the bigger living room for comparison. The living room has Cornwalls, which get the bass very right, so it will be an interesting comparison.
If anyone has a crossover schematic for any of the coaxes using the Radian 450 1" compression driver, I'd love to know what the values are, out of curiosity.
Thanks! It is sounding very nice and musical.
I had almost no expectations going into it, being that there is literally no info on this driver online. It turns out it's a wonderful, musical coax.
I'm a Tannoy guy and will be shooting these Radians out against some SRM 12s shortly for a 'make it or break it' comparo.