I just assembled a pair of 2-ways using the HiVi T20 tweeter and Peerless 830656 5.25" mid. I had some spare crossover components and used all of them in a design using Jeff Bagby's spreadsheet. I was stubborn with the design, I basically made it work with the components I had on hand. The resulting response is:
http://photos.swinbank.fastmail.net/moser/PeerlessHiViT20_response.jpg
3rd order parallel on tweeter with L-pad: 3.3uF, 0.25Mh, 10uF, 2.5ohm (series) and 14ohm (parallel)
2nd order parallel on woofer: 1.0Mh, 4.7uF.
The box has a 180mm wide baffle rounded over at the sides, has a 7.5L volume and a 1.5" port on the rear tuned to about 60-65Hz. These things sound great, I love Peerless woofers. The tweeter is a bit bright but I'll change the resistor values on the L-pad at some point after I break the drivers in. Here is a picture of them, the box is in primer, will paint later:
http://photos.swinbank.fastmail.net/moser/PeerlessHiViT20_1.jpg
The tweeter snaps into the cutout perfectly (I initially cut a larger hole then filled it with an epoxy resin before cutting the right size recess diameter of 52mm). Don't need screws but want to cover the holes, suggestions?
If anyone has worked with these drivers and has any suggestions on crossover design I'd like to know about it!
http://photos.swinbank.fastmail.net/moser/PeerlessHiViT20_response.jpg
3rd order parallel on tweeter with L-pad: 3.3uF, 0.25Mh, 10uF, 2.5ohm (series) and 14ohm (parallel)
2nd order parallel on woofer: 1.0Mh, 4.7uF.
The box has a 180mm wide baffle rounded over at the sides, has a 7.5L volume and a 1.5" port on the rear tuned to about 60-65Hz. These things sound great, I love Peerless woofers. The tweeter is a bit bright but I'll change the resistor values on the L-pad at some point after I break the drivers in. Here is a picture of them, the box is in primer, will paint later:
http://photos.swinbank.fastmail.net/moser/PeerlessHiViT20_1.jpg
The tweeter snaps into the cutout perfectly (I initially cut a larger hole then filled it with an epoxy resin before cutting the right size recess diameter of 52mm). Don't need screws but want to cover the holes, suggestions?
If anyone has worked with these drivers and has any suggestions on crossover design I'd like to know about it!
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Not explicitly but some baffle step is inherent in the crossover with a reduction of about 5dB across the frequency range (from 200Hz to 9kHz)?
Is this more like what you had in mind?
http://photos.swinbank.fastmail.net/moser/PeerlessHiViresponseBSC.jpg
I increased the woofer inductance from 1.0Mh to 1.5Mh, and decreased the parallel resistor on the L-pad from 14ohm to 8ohm. It also reduces the crossover point to 3kHz which may be a bit low for these tweeters.
I calculate 630Hz as the point of diffraction loss. It's hard to start from this point without reworking the crossover or adding a parallel RL circuit.
http://photos.swinbank.fastmail.net/moser/PeerlessHiViresponseBSC.jpg
I increased the woofer inductance from 1.0Mh to 1.5Mh, and decreased the parallel resistor on the L-pad from 14ohm to 8ohm. It also reduces the crossover point to 3kHz which may be a bit low for these tweeters.
I calculate 630Hz as the point of diffraction loss. It's hard to start from this point without reworking the crossover or adding a parallel RL circuit.
Yes that's more along the lines of what I'd be considering. I am not sure how the Bagby spreadsheets etc work, but there are guides at the FRD consortium I think that describe exactly what it is you're supposed to be doing.
This includes extracting the drivers phase, simulating baffle step and baffle diffraction and putting everything together.
The frequency at which baffle step occurs is related directly to the width of the cabinet. The transition, in a completely open space, would cover 6dB with any boundaries causing this value to go down. Some speakers are specifically designed to placed on walls etc and do not use any baffle step compensation, some are intended to be placed further away from walls and will use only around 2-3dB. Whereas speakers intended to be placed well out into the room will use around 4-5dB depending on the bass alignment used.
It is rare that you will see a speaker with the full 6dB. Even 2.5 ways, which are intrinsically compensated for the whole 6dB do not hit the full 6dB due to series pass element insertion losses.
This includes extracting the drivers phase, simulating baffle step and baffle diffraction and putting everything together.
The frequency at which baffle step occurs is related directly to the width of the cabinet. The transition, in a completely open space, would cover 6dB with any boundaries causing this value to go down. Some speakers are specifically designed to placed on walls etc and do not use any baffle step compensation, some are intended to be placed further away from walls and will use only around 2-3dB. Whereas speakers intended to be placed well out into the room will use around 4-5dB depending on the bass alignment used.
It is rare that you will see a speaker with the full 6dB. Even 2.5 ways, which are intrinsically compensated for the whole 6dB do not hit the full 6dB due to series pass element insertion losses.
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