Per stereophile, the ML panel has an acoustic rolloff of 12db, combined with a 12db give an effective XO of 24db.
Since my speakers do not have an acoustic roll off at the 250 XO point, I will stick with 24db xo.
Since my speakers do not have an acoustic roll off at the 250 XO point, I will stick with 24db xo.
I have a vague recollection of ML using two woofers and manipulating the phase. The woofer module is a dipole at its upper end and a monopole at the lower end.
Hopefully a Martin-Logan owner will chime in.
Ed
Hopefully a Martin-Logan owner will chime in.
Ed
Hi,
symmetrical acoustical filter flanks of two xover branches are one important design aim.
Smooth gradual transition of the different distribution character is the second.
ML Sequel2 and much more so the first Sequel were examples where both criteria did not apply.
The resulting sound character was one of a slow, lagging bass uncapable of following the fast esl.
A improvement came with the ML Summit which utilized a second bass driver that was driven in a way that the transition problem of distribution character was mildered.
You probabely can't better results with just a single bass box mounted below a dipolar panel.
It requires a midbass tower and a dedicated low sub to eliminate the transition problem.
But the associated higher effort in material, cost and size as well as different looks appear commercially less attrative than the classic one box fits all concept.
jauu
Calvin
symmetrical acoustical filter flanks of two xover branches are one important design aim.
Smooth gradual transition of the different distribution character is the second.
ML Sequel2 and much more so the first Sequel were examples where both criteria did not apply.
The resulting sound character was one of a slow, lagging bass uncapable of following the fast esl.
A improvement came with the ML Summit which utilized a second bass driver that was driven in a way that the transition problem of distribution character was mildered.
You probabely can't better results with just a single bass box mounted below a dipolar panel.
It requires a midbass tower and a dedicated low sub to eliminate the transition problem.
But the associated higher effort in material, cost and size as well as different looks appear commercially less attrative than the classic one box fits all concept.
jauu
Calvin
I do have a dedicated 15 inch sub for the real deep, crossed at 50 or 60 hz.
As you note, a tower of subs is not very economical...
Here is hoping one for each improves the mid-bass, maybe with some EQ boost...
As you note, a tower of subs is not very economical...
Here is hoping one for each improves the mid-bass, maybe with some EQ boost...
At the moment low pass at 55Hz. I am still experimenting with the crossover. Maybe high pass the LRS+, we will see.
I use a Yamaha pro amp, maybe you can see it in the picture. Reversing half the drivers, but also reverse the phase on them. This has the advantage to cancel out spider resonances. Maybe you can hear them, may be not, But the look cool! And GR research and others are doing the same. I can see them cancelling out thought, on my impedance measurements but they are outside of the used frequency range.
I use a Yamaha pro amp, maybe you can see it in the picture. Reversing half the drivers, but also reverse the phase on them. This has the advantage to cancel out spider resonances. Maybe you can hear them, may be not, But the look cool! And GR research and others are doing the same. I can see them cancelling out thought, on my impedance measurements but they are outside of the used frequency range.
After I posted I guessed it was nulling any acoustic issues the way balanced cables null then out.
What amps are driving them?
What amps are driving them?
Did I miss it, or has someone mentioned an open baffle line array of woofers yet? Magnepan has been demonstrating the UBS comprising 4 forward and 4 backward firing 6 " woofers for a while now, so I am surprised that there isn't some similar DIY approach.
As I understood it it is not the intention to set the tweeter level to -9... it's rather that the LF and HF meets at -9 dB down, rather than -6, as the original filters was symmetrical - no?
If there aren't any resistors in the original filters but only cpas and coils, the passband levels are already matched naturally and no level attenuations should be incorporated in the filters. Where x-overs meet there is, in some filters designs, dips - some don't have it.
//
That configuration doesn't cancel spider resonances. 🙂 It does reduce even-order distortion because half the drivers are operating "inversely" to the other half.
You have way more woofers there than would be needed for SPL matching to the LRS+. But, you have sufficient capability should you go to larger Magnepan's.
What you don't have there is any sort of mechanical force cancellation, since all cones are moving in the same direction all the time.
Dave.
Dear Dave, thank you very much for the correction!
I plan to audition the 1.7i or the new 1.7x in the future, and see if I I like them more than the LRS+.
I really like the bass now.
I plan to audition the 1.7i or the new 1.7x in the future, and see if I I like them more than the LRS+.
I really like the bass now.
I have the Magnepan 1.6 and have previously built and used a Ripole similar to the Linkwitz Phoenix Woofer3. More recently a pair of open baffle dual 12" servo subs. However, I am really curious about a line array that can sit alongside the planar. This appeals because:
1. Potentially lower cost than a pair of servo open baffle subs,
2. A line array might better match the propagation characteristics of a planar and there may be an advantage in soundstage/imaging by keeping the mid-bass/bass tied to the planars rather than as separately located subs
3. Staying with non-servo conventional drivers leaves the option to do the cross over at line level and biamp in the future
4. The structure could be built so as to brace the planar - which seems a very popular mod among Maggie owners (but not something I have tried)
An open baffle vertical line array of multiple identical woofers. This is not a full range speaker, but a mid bass project. Ideally I'd like to see performance down to <40Hz and up beyond 1kHz. Gain would be matched to a planar at ~85dB. Crossover would be in the Lower frequencies for mostly non-musical / HT purposes could be dealt with by a pair of El-Pipe-Os (ref. Nelson Pass)
What information do I need to know in order to get a reasonable idea of the spectrum of the output?
I am thinking of an L shaped baffle (foot of L is towards listener and vertical part back away from listener). It would be a tall thin structure placed alongside (or even fixed/clamped to) Magnepan on the bass side of the panel. This way we can use the planar itself as part of the face of the baffle; i.e. the footprint would be an L with the base of the woofer baffle next to the planar. so as to use the face of the planar to effectively increase the size of the baffle So from above the stereo pair (tweeters in), might look like this.
"I___ ___I"
This would give a front baffle that is say 20" wide and the side of the woofer array that is away from the planar (the vertical part of the L), would go backwards away from the listener about 8".
I'd like to consider 10x Dayton CF120-4 so about 50" high, in other words a similar height to the Magnepan.
Is there anyone out there who has the skills and generosity to model this for me/public consumption?
thanks
1. Potentially lower cost than a pair of servo open baffle subs,
2. A line array might better match the propagation characteristics of a planar and there may be an advantage in soundstage/imaging by keeping the mid-bass/bass tied to the planars rather than as separately located subs
3. Staying with non-servo conventional drivers leaves the option to do the cross over at line level and biamp in the future
4. The structure could be built so as to brace the planar - which seems a very popular mod among Maggie owners (but not something I have tried)
An open baffle vertical line array of multiple identical woofers. This is not a full range speaker, but a mid bass project. Ideally I'd like to see performance down to <40Hz and up beyond 1kHz. Gain would be matched to a planar at ~85dB. Crossover would be in the Lower frequencies for mostly non-musical / HT purposes could be dealt with by a pair of El-Pipe-Os (ref. Nelson Pass)
What information do I need to know in order to get a reasonable idea of the spectrum of the output?
I am thinking of an L shaped baffle (foot of L is towards listener and vertical part back away from listener). It would be a tall thin structure placed alongside (or even fixed/clamped to) Magnepan on the bass side of the panel. This way we can use the planar itself as part of the face of the baffle; i.e. the footprint would be an L with the base of the woofer baffle next to the planar. so as to use the face of the planar to effectively increase the size of the baffle So from above the stereo pair (tweeters in), might look like this.
"I___ ___I"
This would give a front baffle that is say 20" wide and the side of the woofer array that is away from the planar (the vertical part of the L), would go backwards away from the listener about 8".
I'd like to consider 10x Dayton CF120-4 so about 50" high, in other words a similar height to the Magnepan.
Is there anyone out there who has the skills and generosity to model this for me/public consumption?
thanks
