Hello
My question is very simple:
Can a tweeter / compression driver, of high spl, padded too much down, and if so how mutch is too much?
Lets say for example i have a 110 db compression driver and a 90 db woofer. Is there any serious issues (or benefits), with lowering the spl of the tweeter by 20-25 db, using a l-pad in a passive crossover?
Does too much attenuation distort the signal in any way? I mean its normaly the other way around.😉 So could it potentially lower distortion? .
I know l-pads are commonly used, but normaly for smaller corrections. I cant find any info about this problem.
I also know that a lot of energy would be wasted, but i guess its better than a tweeter playing +20 db from the woofer.
Thanks in advance 🙂
My question is very simple:
Can a tweeter / compression driver, of high spl, padded too much down, and if so how mutch is too much?
Lets say for example i have a 110 db compression driver and a 90 db woofer. Is there any serious issues (or benefits), with lowering the spl of the tweeter by 20-25 db, using a l-pad in a passive crossover?
Does too much attenuation distort the signal in any way? I mean its normaly the other way around.😉 So could it potentially lower distortion? .
I know l-pads are commonly used, but normaly for smaller corrections. I cant find any info about this problem.
I also know that a lot of energy would be wasted, but i guess its better than a tweeter playing +20 db from the woofer.
Thanks in advance 🙂
sound will become "darker" and "warmer", the English sound. I enjoy this. In my car Ive adjusted the treble to -10dB and I can so much smoother sound.
The problem doing it on the driver itself instead of eq is that the crossover point to the midbass will be werd like a shelving.
The problem doing it on the driver itself instead of eq is that the crossover point to the midbass will be werd like a shelving.
You must pad as needed to match woofer level, if you want flat response.
And padding is linear, so no distortion added.
And padding is linear, so no distortion added.
Price? Sometimes cheap speakers are left with too much treble. It does draw attention to them.
Attenuating is a good opportunity to reduce impedance variations with resistors. It can also be used to arrive at an arbitrary impedance to suit some special amp.
Attenuating is a good opportunity to reduce impedance variations with resistors. It can also be used to arrive at an arbitrary impedance to suit some special amp.
"Attenuating is a good opportunity to reduce impedance variations with resistors. It can also be used to arrive at an arbitrary impedance to suit some special amp."
😛
Every time I hear mention of using resistors to arrive at an arbitrary impedance, I remember PWK's tongue in cheek Ultimate LSH. 😛😀
https://2d73e25b29782b6d6766-9c8af5...timate_LSH_Loudspeaker_635110470606040000.pdf
😛
Every time I hear mention of using resistors to arrive at an arbitrary impedance, I remember PWK's tongue in cheek Ultimate LSH. 😛😀
https://2d73e25b29782b6d6766-9c8af5...timate_LSH_Loudspeaker_635110470606040000.pdf
That's funny. I remember being told by a Hi-Fi salesman that "The lower the efficiency, the better the speaker" about the time this article was written. And I believed it!! 😀
I meant like price of the compression driver, horn and l-pad (with expensive parts, high value and power resistors).
But i guess, a compression driver can be just as expensive or cheap as a dome.
So why dont more people pad down a compression driver to match with typical low distortion (90 ish db ) woofers?
I can see from simulations i xsim that the l-pad, flattened the impedace, while raising the impedance. I guess neither really is bad.
Also a small change to phase, but very minor.
But i guess, a compression driver can be just as expensive or cheap as a dome.
So why dont more people pad down a compression driver to match with typical low distortion (90 ish db ) woofers?
I can see from simulations i xsim that the l-pad, flattened the impedace, while raising the impedance. I guess neither really is bad.
Also a small change to phase, but very minor.
Thanks for the link. Classic 😀
Marcusrm, the way I see it, not bringing the treble to the correct level is simply incorrect (unless there is a special reason), so who knows why some don't, but yes you should.
If you have trouble with phase or other things, it isn't because you're doing this.. it's because of how.
Marcusrm, the way I see it, not bringing the treble to the correct level is simply incorrect (unless there is a special reason), so who knows why some don't, but yes you should.
If you have trouble with phase or other things, it isn't because you're doing this.. it's because of how.
That makes sense. And yes, i agree, not bringing the level of the tweeter down to match the woofer, does not make sense.
But if there is nothing wrong with attenuning 20 db or more, i dont see why more people don't combine high spl compression drivers, with low spl woofers.
Most systems i have seen have drivers that "almost" match, and just minor attenuatinon (1-3 db ish)
But if there is nothing wrong with attenuning 20 db or more, i dont see why more people don't combine high spl compression drivers, with low spl woofers.
Most systems i have seen have drivers that "almost" match, and just minor attenuatinon (1-3 db ish)
Lower efficiency 'hifi' woofers aren't always the best choice for using up into their breakup region. Have you noticed regular waveguide speakers also use a large diameter woofer to match directivity?
I hate to mention it - and will probably regret it, but some people think that resistors kill the life of compression drivers. I find it mostly tames them, but perhaps it's the wild edge that people miss. 🙂
I've read that a few times over the years but so far I haven't noticed any negative effects. It's a very simple passive component... get ready to lock the thread 😛
I use them to get prosound amps out of the milliwatt range and lower the noisefloor.
I use them to get prosound amps out of the milliwatt range and lower the noisefloor.
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The wild edge 😉 The thing with removing distortions (that includes response issues) is that you don't always know what's underneath. (basically agreeing)
Concentric Coaxial drivers use compression drivers
Plenty of 8 inch versions with efficiency of 92 to 95dB and their compression drivers range from 105 to 109dB or higher. They pad the heck out of them to get them even so it does happen. I saw a 8 inch two-way using an 87dB woofer matched up with a 109dB compression driver and 10" horn--it worked well.
I am putzing around with a 93dB 6.5 inch coaxial woofer and want to cram in a 109dB compression driver--it holds over 110dB at one watt from 2KHz to 10KHz before drifting down to 105dB at 18KHz... this is going to be fun with resistor time!
Plenty of smaller PA speakers, say 8 inch or smaller use compression drivers that the "big boys" use and they work very well. Good question though--I never thought about it.
Plenty of 8 inch versions with efficiency of 92 to 95dB and their compression drivers range from 105 to 109dB or higher. They pad the heck out of them to get them even so it does happen. I saw a 8 inch two-way using an 87dB woofer matched up with a 109dB compression driver and 10" horn--it worked well.
I am putzing around with a 93dB 6.5 inch coaxial woofer and want to cram in a 109dB compression driver--it holds over 110dB at one watt from 2KHz to 10KHz before drifting down to 105dB at 18KHz... this is going to be fun with resistor time!
Plenty of smaller PA speakers, say 8 inch or smaller use compression drivers that the "big boys" use and they work very well. Good question though--I never thought about it.
What happens with padding is that the introduction of a series resistance introduces a mix between voltage drive and current drive. Some drivers have lower distortion with current drive, so that may be a good thing. At the same time, impedance variations in the driver will cause variations in the frequency response. A driver that is straight before padding may no longer be after, and vice versa.
On the whole, all high drivers are padded down to the level of the other drivers, so manufacturers are aware that their products may be used with a series resistance.
On the whole, all high drivers are padded down to the level of the other drivers, so manufacturers are aware that their products may be used with a series resistance.
resistors should be cheaper than using an autoformer such as Klipsch. That will reflect a high Z which in turn could reduce (fancy) capacitor cost.
Here's an Edcor transformer
Here's an Edcor transformer
Padding down compression drivers/maybe ESS
AllenB:
I didn't look at this site much in 2020, but took a peek today, and read this post with interest. Just prior, I caught up on Pelanj and his ESS Heil project. I've been listening to my large ESS driver for nearly a year now, and really like them.
I'm interested in what the OP asked about mating high efficiency stuff to low 90's woofers. Could the same effect of lowering output of treble be done simply with an active crossover? If so, are there other considerations that could affect sound quality? In my case, I want to use new drivers sitting on my shelves for years. Take the Heils I bought a year ago, use a TAD 12' midbass (100db) but mate to some Eminence 15" woofers from DIYSG, that I believe sit at about 93db or so. I'd be looking at crossover points at around 300/800 for a 3 way. I've always been told to get a woofer the same efficiency or close, but right now I don't want to add even more drivers to my collection. I'm terrible at getting around to selling anything, so that won't happen. I have the active crossover, and the amps.
Hope I'm not hijacking the thread, but it sounds close to what the OP is asking. The ESS has output in the same general range as some compression drivers, so I'd worry about losing some of the qualities I like from them.
AllenB:
I didn't look at this site much in 2020, but took a peek today, and read this post with interest. Just prior, I caught up on Pelanj and his ESS Heil project. I've been listening to my large ESS driver for nearly a year now, and really like them.
I'm interested in what the OP asked about mating high efficiency stuff to low 90's woofers. Could the same effect of lowering output of treble be done simply with an active crossover? If so, are there other considerations that could affect sound quality? In my case, I want to use new drivers sitting on my shelves for years. Take the Heils I bought a year ago, use a TAD 12' midbass (100db) but mate to some Eminence 15" woofers from DIYSG, that I believe sit at about 93db or so. I'd be looking at crossover points at around 300/800 for a 3 way. I've always been told to get a woofer the same efficiency or close, but right now I don't want to add even more drivers to my collection. I'm terrible at getting around to selling anything, so that won't happen. I have the active crossover, and the amps.
Hope I'm not hijacking the thread, but it sounds close to what the OP is asking. The ESS has output in the same general range as some compression drivers, so I'd worry about losing some of the qualities I like from them.
Yes, of course you could do it at line level. There would, since you ask, be various minor differences (as there always seem to be), the kinds that get less the more we understand about them.. So for now, assume there won't be any.
One issue as I mentioned earlier. It happens that a woofer for use with a waveguide gets used right up to breakup. Paper cones and pleated surrounds aren't such a bad choice considering this. If you don't use a pro woofer you might find more that don't play well enough at the top end.
One issue as I mentioned earlier. It happens that a woofer for use with a waveguide gets used right up to breakup. Paper cones and pleated surrounds aren't such a bad choice considering this. If you don't use a pro woofer you might find more that don't play well enough at the top end.