I read an article from JL Audio about using a secondary set of tweeters to help raise your sound stage (imaging tweeters). I've never done that, but it makes sense to me intuitively.
My current midrange drivers are about half way up on the doors with tweeters in the sail panels. They do the job, but...
Since reading that article, I've become obsessed with the idea of using an 'imaging midrange' in a similar way.
I have two small midrange speakers (Dayton RS75, optimal 600-6000k) that I have no other use for, and my A pillars have a perfect spot for them. I also have DSP capacity to control their level, time alignment, etc. I know there's potential for phase issues, etc.... but could it work?
I'd probably never recommend someone do this when planning a system from scratch, but I can't help but wonder if it would be possible or beneficial (fuller, louder, deeper, or higher sound in the midrange).
I've personally never seen it done (that might be my first clue that it's doomed to fail!). I'd just try it, but it'll be a bit of a PITA and a lot of wasted time if it's a dud of an idea (and I've had too many of those lately!).
I don't know... any thoughts about this? LOTS of you have bigger brains and much more experience, so I'm hoping you can save me some trouble, smack me in the face... something! lol
My current midrange drivers are about half way up on the doors with tweeters in the sail panels. They do the job, but...
Since reading that article, I've become obsessed with the idea of using an 'imaging midrange' in a similar way.
I have two small midrange speakers (Dayton RS75, optimal 600-6000k) that I have no other use for, and my A pillars have a perfect spot for them. I also have DSP capacity to control their level, time alignment, etc. I know there's potential for phase issues, etc.... but could it work?
I'd probably never recommend someone do this when planning a system from scratch, but I can't help but wonder if it would be possible or beneficial (fuller, louder, deeper, or higher sound in the midrange).
I've personally never seen it done (that might be my first clue that it's doomed to fail!). I'd just try it, but it'll be a bit of a PITA and a lot of wasted time if it's a dud of an idea (and I've had too many of those lately!).
I don't know... any thoughts about this? LOTS of you have bigger brains and much more experience, so I'm hoping you can save me some trouble, smack me in the face... something! lol
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No problem as long as the two midranges aren't playing the same frequencies. But why not just move the door midrange to your pillars? What size is the midrange in your door?
Hey, Velozity... thanks for chiming in. Yeah, I imagined overlapping the passbands would cause a constructive/destructive mess, so it's good advice to separate them.
Why not move the midrange to the pillars? It's a good question. The one that would work particularly well in the pillar (because it's small--~2.5") doesn't play particularly low (maybe down to 500ish).
The midrange in the door (currently playing 300-4000) is a 5-1/4." I was thinking of keeping that 5-1/4 as 'low midrange' (maybe 300-900hz), and using the smaller driver as an 'upper midrange' (maybe 900-5000hz).
I never hear of anyone doing this, so I wonder how feasible or desirable it would be. 🤔
Why not move the midrange to the pillars? It's a good question. The one that would work particularly well in the pillar (because it's small--~2.5") doesn't play particularly low (maybe down to 500ish).
The midrange in the door (currently playing 300-4000) is a 5-1/4." I was thinking of keeping that 5-1/4 as 'low midrange' (maybe 300-900hz), and using the smaller driver as an 'upper midrange' (maybe 900-5000hz).
I never hear of anyone doing this, so I wonder how feasible or desirable it would be. 🤔
Hey, Perry! You've helped me before... always good to hear your opinions.
Can I get your gut reaction to this:
The midrange in the door (currently playing 300-4000) is a 5-1/4." I was thinking of keeping that 5-1/4 as 'low midrange' (maybe 300-900hz), and using the smaller driver as an 'upper midrange' (maybe 900-5000hz).
Do you think blending two will be difficult if they're not close together? Any ideas? Thanks, my friend!
Can I get your gut reaction to this:
The midrange in the door (currently playing 300-4000) is a 5-1/4." I was thinking of keeping that 5-1/4 as 'low midrange' (maybe 300-900hz), and using the smaller driver as an 'upper midrange' (maybe 900-5000hz).
Do you think blending two will be difficult if they're not close together? Any ideas? Thanks, my friend!
If they're crossed over to prevent too much overlap, I don't think they will have trouble interfering with each other. I'd suggest getting everything as close as possible to 'good' and then employ the DSP just to clean it up.
Remember that speakers have an impedance that's far from flat and a simple crossover (no conjugate networks/impedance compensation), could leave you with peaks/dips where you don't expect them. This could be more of a problem than blending.
Is every speaker going to be driven by an independent amplifier channel and each channel driven by a dedicated output from the DSP?
Do you have an RTA?
Remember that speakers have an impedance that's far from flat and a simple crossover (no conjugate networks/impedance compensation), could leave you with peaks/dips where you don't expect them. This could be more of a problem than blending.
Is every speaker going to be driven by an independent amplifier channel and each channel driven by a dedicated output from the DSP?
Do you have an RTA?
Yeah, Perry... I have a DSP and a dedicated channel to each speaker... and REW with a calibrated microphone. I'm not an expert tuner, but I have some experience.
I know it's preferable to have your tweeter close to your midrange to prevent perturbations in your stage when you move your head around (I think that's right). I'm not sure if that's important with two midranges--or would it be cool if they were ~16 inches apart?
I know it's preferable to have your tweeter close to your midrange to prevent perturbations in your stage when you move your head around (I think that's right). I'm not sure if that's important with two midranges--or would it be cool if they were ~16 inches apart?
With a pure sine wave, you may be able to tell the difference but with speakers (specified because headphones eliminate a lot of problems), there are so many other issues.
You could test to see if you can hear the difference. Move one channel's speakers to the new configuration and leave one channel as-is. Sit as close to the center of the vehicle as possible and play one channel (alone) then switch to the other channel (alone). Can you hear a difference as you move your head? Is there enough a difference to make the changes?
Then you have to think about the difference in the angle/axis. Speakers sound very different on/off axis. Maybe the differences in what you hear are just that.
What about the reflections off of glass that will cause phase problems that may not exist when the mids are mounted in upholstery (or somewhere that's less reflective than glass).
It's also difficult to defeat expectations and biases. You can't test double-blind so what you expect to hear (improvement or not), may not be what someone else might hear with the changes. Keep an open mind.
You could test to see if you can hear the difference. Move one channel's speakers to the new configuration and leave one channel as-is. Sit as close to the center of the vehicle as possible and play one channel (alone) then switch to the other channel (alone). Can you hear a difference as you move your head? Is there enough a difference to make the changes?
Then you have to think about the difference in the angle/axis. Speakers sound very different on/off axis. Maybe the differences in what you hear are just that.
What about the reflections off of glass that will cause phase problems that may not exist when the mids are mounted in upholstery (or somewhere that's less reflective than glass).
It's also difficult to defeat expectations and biases. You can't test double-blind so what you expect to hear (improvement or not), may not be what someone else might hear with the changes. Keep an open mind.
So... you're saying that tuning's not that straightforward?? lol Man, the more I get into it, the more I think it's a rabbit hole that I'll just keep tumbling down, never reaching 'paradise.' I love what you said about 'keeping an open mind.' It's fascinating how some things I'm sure will work don't... and vice-versa. A car environment sometimes feels like the Wild West... you just have to venture into it and see what happens.
Awesome suggestions, Perry... really appreciate your taking the time!
Awesome suggestions, Perry... really appreciate your taking the time!
I have had great results with dash mounted mids/tweeters, aimed to reflect off of the windshield. The tweeter and 4” mid were located close together and individually aimed.
The target was to have the rh speakers aimed to end up at your left ear and vice versa on the opposite side.
It takes some patience, I used metal plumbers tape that could be bent and re-bent until it was right.
That gave the best “stage” or presentation I have experienced so far. The drivers were MB Quart 4”, and JBL titanium tweeters. A pair of 8” were up behind the dash, aimed at the floor, in sealed boxes. The tweeters were padded down and also setup to play lower.
The target was to have the rh speakers aimed to end up at your left ear and vice versa on the opposite side.
It takes some patience, I used metal plumbers tape that could be bent and re-bent until it was right.
That gave the best “stage” or presentation I have experienced so far. The drivers were MB Quart 4”, and JBL titanium tweeters. A pair of 8” were up behind the dash, aimed at the floor, in sealed boxes. The tweeters were padded down and also setup to play lower.
A pair of 8s "up behind the dash"?? What kind of vehicle is this... sounds like a dream!
Man, would it be too much trouble to ask for a pic of your setup? I'm having a little trouble visualizing it (e.g., 'tweeters padded down'). Frankly, I'd just love to see it!
Man, would it be too much trouble to ask for a pic of your setup? I'm having a little trouble visualizing it (e.g., 'tweeters padded down'). Frankly, I'd just love to see it!
Right, same focusing layout as required for HIFI stereo depth of field/'staging', which I found was best at a focal point just in front of my face, so curious if it works in a vehicle also or.........?
It was in a couple year old base Fiero, so no A/C behind the passenger side dash. The 8” were in boxes that were very small, stuffed with fiberglass insulation. The factory dash speakers were 5x7, so the 4” and tweeter had plenty of room for manipulation. Couldn’t see any of it, which was good since the car didn’t even have functioning locking doors, must’ve been part of that great GM feeling.
I never got any pictures of it, removed the setup when I sold the car to try and raise tuition for school.
Part of the reason it worked was because there wasn’t anything behind you, was just a tiny, well upholstered space with fairly close to equal distance from where each speaker bounced its sound off a part of the car and back to your ears. Also the 8” were mounted outboard for a bit of corner loading. Was powered by a 30W Profile amp running off the Delco head unit.
The passive crossovers were what came with the MB Quart three-way set, but I may have used some coils with the 8”, don’t recall. The ti tweeters were bright but great compared to the quart ones.
With the options available today using adjustable time alignment, should be possible to make something work, even working around airbags, etc.
I never got any pictures of it, removed the setup when I sold the car to try and raise tuition for school.
Part of the reason it worked was because there wasn’t anything behind you, was just a tiny, well upholstered space with fairly close to equal distance from where each speaker bounced its sound off a part of the car and back to your ears. Also the 8” were mounted outboard for a bit of corner loading. Was powered by a 30W Profile amp running off the Delco head unit.
The passive crossovers were what came with the MB Quart three-way set, but I may have used some coils with the 8”, don’t recall. The ti tweeters were bright but great compared to the quart ones.
With the options available today using adjustable time alignment, should be possible to make something work, even working around airbags, etc.
Very interesting. A Fiero... wow. If you had told me you could put two 8s in a Fiero dash, I'd have said you were crazy! lol
Yeah, that's an interesting cabin space. It's been a while, but I had a standard-cab truck (the mini-trucks of the 90s) with the subs ported through the bed into the cabin. I was a lot younger, and the front 'stage' wasn't anything sophisticated, but I thought it sounded wonderful.
I wonder if a small cabin space is easier to tame or get good results? Never really thought about it...
As you said, though, with today's equipment, I think you can make anything work!
Thanks for sharing!
Yeah, that's an interesting cabin space. It's been a while, but I had a standard-cab truck (the mini-trucks of the 90s) with the subs ported through the bed into the cabin. I was a lot younger, and the front 'stage' wasn't anything sophisticated, but I thought it sounded wonderful.
I wonder if a small cabin space is easier to tame or get good results? Never really thought about it...
As you said, though, with today's equipment, I think you can make anything work!
Thanks for sharing!
You definitely don’t need as much power in a smaller volume interior. That car was like a large pair of headphones, lol.
Also had a bit of rear fill from the oem headrest speakers and some additional smaller speakers in the sail panels, but their contribution was minimal.
Just remember that small drivers will beam, and to be very open with aiming before establishing any firm mounting. It helps to try just one driver at a time also, will make things more obvious. The angle of the glass/seating position are other factors, and it may just work best with the conventional arrangement, with the drivers outboard on the pillars and facing each other.
A different setup had a center channel that was a pair of low powered 3-4” around where the center air ducts would be, and that helped the presentation. It helped make up for door mounted speakers.
Also had a bit of rear fill from the oem headrest speakers and some additional smaller speakers in the sail panels, but their contribution was minimal.
Just remember that small drivers will beam, and to be very open with aiming before establishing any firm mounting. It helps to try just one driver at a time also, will make things more obvious. The angle of the glass/seating position are other factors, and it may just work best with the conventional arrangement, with the drivers outboard on the pillars and facing each other.
A different setup had a center channel that was a pair of low powered 3-4” around where the center air ducts would be, and that helped the presentation. It helped make up for door mounted speakers.