Hi all
we’ve finished with a friend a pair of bass reflex columns (similar in proportions to pensils seen on this forum) with an alpair 10p in each.
Have gone through hundreds of mails to read about experience with passive equalisation, baffle step compensation, equalisation, notch filter, BSC or whatever it’s called. Can’t get a real picture of what end values are giving satisfaction.
I would appreciate a quick feedback from those who have kept such a passive equalisation and what values are used for an LCR or LR circuit and possibly impedance correction (R or RC) in parallel. Thanks a lot in advance!
we’ve finished with a friend a pair of bass reflex columns (similar in proportions to pensils seen on this forum) with an alpair 10p in each.
Have gone through hundreds of mails to read about experience with passive equalisation, baffle step compensation, equalisation, notch filter, BSC or whatever it’s called. Can’t get a real picture of what end values are giving satisfaction.
I would appreciate a quick feedback from those who have kept such a passive equalisation and what values are used for an LCR or LR circuit and possibly impedance correction (R or RC) in parallel. Thanks a lot in advance!
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I don't hink the 10P needs filtering at all. It does not have strong resonances as it's a paper cone and the impendance is reasonable flat untill FS. Filtering is mainly needed when using drivers with a rising top or heavy resonances which this driver does not have. The top is even a bit to tamed for my taste (but only a little bit). Best is to run it full open without filtering.
I have never had to use any of these band-aids on the A10p. U=It does need a reasonable break-in. A week playing on th ebench at low levels cover sof fmost of it.
dave
Get rid of what exactly? A very easy speaker to drive, and as Waxx and Dave suggest, doesn't require filters.
jeff
OK, expanding a little:
Low pass shelving filters are to a point application and system dependent, so there isn't actually a fixed answer other than 'what works optimally for your particular setup / preferences'. As usual, we work with context (or should 😉 ).
The 10P has in some enclosures a slightly rising low end response, which when combined with room gain can cancel out most practical step-losses. It also has (as noted above) a rolled off top end, which again can have the impression of balancing the general presentation.
One thing you have to be careful of is that many / most shelving filters (at least, those done with wideband drive units) are created using only the on-axis response. Unless it's a relatively extreme case, and / or the driver has extremely good off-axis behaviour, that can come back to bite you, especially in larger spaces. Due to the limited HF dispersion of most wideband drivers (the MAs are better than many, as they have shallow cone profiles & direct-coupled central domes, but they can't work miracles) if you EQ the on-axis response flat, they can end up sounding a bit 'dull' as this also attenuates the off-axis output. The same applies to quality multiway designs. For e.g., I'm currently working on a new 2-way with a 3in mid-tweeter; on-axis, it has a 1dB rising response trend for exactly this reason.
None of this is to say low-pass shelving filters have no place -they can be useful. But it's also easy to go too far for the above & other reasons, so avoid generics where possible and design according to your own requirements.
Low pass shelving filters are to a point application and system dependent, so there isn't actually a fixed answer other than 'what works optimally for your particular setup / preferences'. As usual, we work with context (or should 😉 ).
The 10P has in some enclosures a slightly rising low end response, which when combined with room gain can cancel out most practical step-losses. It also has (as noted above) a rolled off top end, which again can have the impression of balancing the general presentation.
One thing you have to be careful of is that many / most shelving filters (at least, those done with wideband drive units) are created using only the on-axis response. Unless it's a relatively extreme case, and / or the driver has extremely good off-axis behaviour, that can come back to bite you, especially in larger spaces. Due to the limited HF dispersion of most wideband drivers (the MAs are better than many, as they have shallow cone profiles & direct-coupled central domes, but they can't work miracles) if you EQ the on-axis response flat, they can end up sounding a bit 'dull' as this also attenuates the off-axis output. The same applies to quality multiway designs. For e.g., I'm currently working on a new 2-way with a 3in mid-tweeter; on-axis, it has a 1dB rising response trend for exactly this reason.
None of this is to say low-pass shelving filters have no place -they can be useful. But it's also easy to go too far for the above & other reasons, so avoid generics where possible and design according to your own requirements.
Very true, that's why off axis measurements are always needed before you do that filtering. The filter i have on my 10.3 is not attenuating the rising top totally, just taming it so it's off axis not to low and on axis not to sharp (but still rising slightly). In my first build with this driver (about 8 years ago i think) i did it too much (aka flat on axis), and it sounded dull, so i removed it fast...
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Ok then. Thanks! We’ll pursue the burning in process and see whether the somewhat harsh upper mid-band gets more civilised after some time and EQ can be omitted or obtained through horizontal orientation of the speakers.
Yeah, it's not exclusive to widebands either (not by a long chalk). You sometimes see criticisms of designs using the XT25 ring-radiator & it's various Scan descendants for sounding a bit dull / lacking at the top end; I suspect at least a good proportion of the time it's because the speaker has been designed to a flat or even a slightly declining HF trend, which can work fine in some cases, but less ideal for the XT25 unless it's being used as a nearfield monitor.
So the 10P seems to be a masterpiece of a speaker today.
I did another pair of speakers with A10 1st generation (bronze coloured metal cone) a few years ago, in a slim column. I needed a bit of taming of the upper mids because of baffle step. So I assumed the 10P was a bit similar.
I did another pair of speakers with A10 1st generation (bronze coloured metal cone) a few years ago, in a slim column. I needed a bit of taming of the upper mids because of baffle step. So I assumed the 10P was a bit similar.
And by the way, I found it interesting to mount two A10 on each column to get more dBs. The project remained in the corner as I still worked on the main system but first trials sounded promising.
A10.2 was WAY better than A10 (the colour is gold), A10.3 better yet, A10p the same voicing as the A6p. Different. Six of one, half dozen of the other.
dave
dave
After a reasonable burn in time, we’ve decided that some eq was definitely needed at this stage. We ended up with L1,2 and R6,8, and added in the end C3 all in parallel on the +. We found the midrange clearly too prominent and even aggressive on certain recordings with female voices (Marla Glen etc). The values will be adjusted as listening tests and burn in continue.
I think EQing the 2 is interesting. Can you post a picture of your setup? I was thinking about a similar 2 driver per channel setup, and in the end decided against it. But I'd still like to see your placement if drivers, how close they are, etc.
Hi elac310. I have a similar experience with paper version as you. For me it sounds like they are out of phase. I tried LCR to tame it down but no luck. What is interesting is that it sounds excelent playing only one speaker. Later I instaled metal version 10.3 in the same box and it sounds much better. Please do continue to report if you make some progres, because I gave up on P version :-(