I have a pair of Blue Sky speakers that were originally active speakers. Due to quality control issues with the first generation PCBs, the amps were unreliable so I wired them to be bi-amped with an Ashley EQ and two AudioSource A/B amps.
Sounds ok but it's a cumbersome setup so I'm looking to convert to passive crossovers. The original specs are
Low Frequency Cutoff 80Hz
Low Frequency Rolloff 12dB per octave
System Q .707
System Crossover Frequency 1.5kHz
System Crossover Slope 4th order Linkwitz-Riley Acoustic
So, I'm looking for this:
xover for 6" driver - high pass 80hz, low pass 1.5khz
xover for tweeter - high pass 1.5khz
However, my Google fu has failed and I haven't been able to locate any crossover with those specs. I'd appreciate any suggestions, even DIY (I can solder but not design).
Thanks!
Sounds ok but it's a cumbersome setup so I'm looking to convert to passive crossovers. The original specs are
Low Frequency Cutoff 80Hz
Low Frequency Rolloff 12dB per octave
System Q .707
System Crossover Frequency 1.5kHz
System Crossover Slope 4th order Linkwitz-Riley Acoustic
So, I'm looking for this:
xover for 6" driver - high pass 80hz, low pass 1.5khz
xover for tweeter - high pass 1.5khz
However, my Google fu has failed and I haven't been able to locate any crossover with those specs. I'd appreciate any suggestions, even DIY (I can solder but not design).
Thanks!
It sounds like you requires a high order slope, two way crossover with a crossover frequency of 1.5 kHz.
Do you know the nominal impedance of the woofer and of the tweeter?
Do you know the nominal impedance of the woofer and of the tweeter?
P.S. I am presuming that the LF roll off and LF cut off are determined by the enclosure of the 6" driver and not by crossover components.
Took a bit of digging - nominal impedance is 4 ohms.
The LF roll off/cut off is a bit weird. So, this is a 2.1 system with a massive 70+lb 12" sub. You plug the audio source into the sub and it goes through an 80hz high pass filter in the sub then out to the 2 speakers. The specs on that high pass filter are:
Gain (balanced in and out) 0dB
High-Pass Filter type 2nd order Linkwitz-Riley
High-Pass Filter Cutoff 80Hz
High-pass Filter Q .707
The LF roll off/cut off is a bit weird. So, this is a 2.1 system with a massive 70+lb 12" sub. You plug the audio source into the sub and it goes through an 80hz high pass filter in the sub then out to the 2 speakers. The specs on that high pass filter are:
Gain (balanced in and out) 0dB
High-Pass Filter type 2nd order Linkwitz-Riley
High-Pass Filter Cutoff 80Hz
High-pass Filter Q .707
It sounds like we need more information on these "Blue Sky" active speakers and their intended use.
They're still around - https://abluesky.com/ Mine are almost 20 years old - I got them from a defunct local recording studio and used them in my video studio for years. I mostly listen rather than produce these days so I want to repurpose them for easier listening.
I sent my post #6 prior to seeing your post #5!
So, you intend to use the pair of satellite speakers fed from the 80 Hz high pass filter incorporated in the 12" sub?
So, you intend to use the pair of satellite speakers fed from the 80 Hz high pass filter incorporated in the 12" sub?
I would rather have an 80hz high pass filter built into the passive crossover. That way, I could swap subs for something more manageable. The Blue Sky sub is a monster made to be played loud - it goes down to 4hz, but, to be honest, it can be a bit "boomy" at the volume I listen to so I'm thinking a 10" Polk I have might give a tighter sound.
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Often main speakers are not crossed above subs, but play along with them. Their room position does the filtering and together they form a more complete arrangement. I mention this because high passing them as you are asking is a task, so you'd want to make sure it's necessary.
If these run out of steam during normal listening then that forces you to consider high-passing. If you use separate amps you may be able to use a line level passive filter if it's convenient.
If these run out of steam during normal listening then that forces you to consider high-passing. If you use separate amps you may be able to use a line level passive filter if it's convenient.
If you are looking for commercially available filters, then check out the suggestions below.
(Without full knowledge of the driver parameters, it isn't possible to design custom crossovers as the experts would advise should be the case.)
1. High pass filter 80 Hz, 4 ohm filter (optional) : https://www.parts-express.com/80-Hz-High-Pass-4-Ohm-Crossover-266-456?quantity=1
2. Low pass filter 2000 Hz, 4 ohm: https://www.parts-express.com/Dayto...ver-2-000-Hz-12-dB-Octave-260-1852?quantity=1
3. High pass filter 2000 Hz, 4 ohm: https://www.parts-express.com/Dayto...ver-2-000-Hz-12-dB-Octave-260-1850?quantity=1
I hope the above is of some practical help in the absence of any other suggestions.
If it’s “boomy” things aren’t adjusted right. Usually, just too much sub overall. Most people use subs just to add a lot more bass in the region the mains can reproduce anyway, rather than just add response below where the mains Peter out. Big difference between turning the sub up and boosting below 40 and only below 40. Having a complementary high/low pass at 80 is an attempt to remedy that, but the tendency is to run subs 10dB hot. You probably just need less heat, but you can get that out of the Blue Sky easily. Then EQ it flat, or to some desired curve. Those Polks are ticking time bombs, and only a matter of time before you need to replace the amplifier (Even if you don’t listen loud).