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How do you know it's clipping? Sounds like a gain issue, as some of the things you said are somewhat contradictory. I.e. if it's clipping at low levels, but plays way more bass with the cambridge turned all the way up, are you thinking that the green signal lights are clipping indicators? Only the top red lights are clipping indicators. You probably need more gain.

Max the knobs on the front of the crown. Adjust input sensitivity to .775V (high sensitivity) on the crown. If adjustable, turn the sub output moderate to high on the cambridge. Re-evaluate.
 

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Discussion Starter #22
How do you know it's clipping? Sounds like a gain issue, as some of the things you said are somewhat contradictory. I.e. if it's clipping at low levels, but plays way more bass with the cambridge turned all the way up, are you thinking that the green signal lights are clipping indicators? Only the top red lights are clipping indicators. You probably need more gain.

Max the knobs on the front of the crown. Adjust input sensitivity to .775V (high sensitivity) on the crown. If adjustable, turn the sub output moderate to high on the cambridge. Re-evaluate.
Its not clipping at low levels, thats not the problem.
I guess i just have to blend the system in with a minidsp, since when i turn the volume knob up to a level where the crown can push my subwoofer better, my main speakers are already distorting.

The suboutput of the cambridge is not adjustable. 0.775V is already set.

The main thing i was wondering is that since this amp is rated at 1550W at 4 ohms i thought that i would damage my sub waaaaaay before the amp goes into clipping?
 

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Things have taken a turn here and it appears that the issue is not what I once though it was from reading your latest posts.

What main speakers do you have? Does the Cambridge have a facility to apply a high pass filter (crossover) to the speakers?

One of the main Benefits to adding a sub is the fact that bass gets redirected from the mains to the sub with bass management. Allowing the speakers to play louder int eh frequency range they excel rather than at a frequency they don’t.

If you don’t have this crossover facility, you are basically in a position where the sub will be supplementing the bass if the mains rather than taking control.

In this instance, your mains are going to run out of puff way before your sub.


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Discussion Starter #24
Things have taken a turn here and it appears that the issue is not what I once though it was from reading your latest posts.

What main speakers do you have? Does the Cambridge have a facility to apply a high pass filter (crossover) to the speakers?

One of the main Benefits to adding a sub is the fact that bass gets redirected from the mains to the sub with bass management. Allowing the speakers to play louder int eh frequency range they excel rather than at a frequency they don’t.

If you don’t have this crossover facility, you are basically in a position where the sub will be supplementing the bass if the mains rather than taking control.

In this instance, your mains are going to run out of puff way before your sub.


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Oh man i guess i just have problems with communicating my problems in english, since its now my main language.

My main speakers are klipsch rp600m . And the cambridge audio cxa81 has like no functions at all.

Yeah but id have to generally just listen very loudly before the sub performs, where i wanted it to be.

But with the minidsp that wouldnt be a problem i guess, since i can give it more gain?
 

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Have you tried using the pre-amp outputs, instead of the sub output ? It staits in the owners manual you can use them to hookup a subwoofer.
 

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I’m not sure a minidsp is going to help you I’m afraid.

It would take the sub output of the Cambridge, digitise it, then you would be able to apply EQ, flatten the response, and use the minidsp to set the sub crossover.

You can also use it to set delays and time alignment the subs to the mains.

However, the crown I’m sure already does this. It digitises the analogue sub out signal and then applies low pass filters and then converts back to analogue for output to the sub itself.

It probably has EQ and delays built in to the crown. Thus no point in the minidsp.

You wouldn’t want to further reduce quality by too many analogue and digital conversions.

You can’t you a minidsp connected after the source and before the Cambridge and set a high pass on your mains because then you wouldn’t be able to use the sub output of the Cambridge as it would have a 2 channel digital signal being sent from the minidsp.

Of you add a minidsp after the Cambridge you may as well not bother with the Cambridge as you won’t be getting the benefit of the good DAC onboard


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Basically. I don’t mean to sound defeatist.

But I think you should have bought a minidsp SHD power instead of the Cambridge.

Then all these problems would be gone.

The Cambridge is meant for full range speakers with complimentary subs. Not limited bookshelf’s


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I’m not sure a minidsp is going to help you I’m afraid.

It would take the sub output of the Cambridge, digitise it, then you would be able to apply EQ, flatten the response, and use the minidsp to set the sub crossover.

You can also use it to set delays and time alignment the subs to the mains.

However, the crown I’m sure already does this. It digitises the analogue sub out signal and then applies low pass filters and then converts back to analogue for output to the sub itself.

It probably has EQ and delays built in to the crown. Thus no point in the minidsp.

You wouldn’t want to further reduce quality by too many analogue and digital conversions.

You can’t you a minidsp connected after the source and before the Cambridge and set a high pass on your mains because then you wouldn’t be able to use the sub output of the Cambridge as it would have a 2 channel digital signal being sent from the minidsp.

Of you add a minidsp after the Cambridge you may as well not bother with the Cambridge as you won’t be getting the benefit of the good DAC onboard


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Just to clarify, the Crown doesn't have much. You can set HPF/LPF but no EQ or delays. If you had a miniDSP and another amp, you could run all of your speakers through the MiniDSP and filter the bass out of your mains, and EQ the sub or delay or whatever. That sounds like the cheapest option given what you already have. Buy a MiniDSP and a used amp for the mains.
 

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Things have taken a turn here and it appears that the issue is not what I once though it was from reading your latest posts.

What main speakers do you have? Does the Cambridge have a facility to apply a high pass filter (crossover) to the speakers?

One of the main Benefits to adding a sub is the fact that bass gets redirected from the mains to the sub with bass management. Allowing the speakers to play louder int eh frequency range they excel rather than at a frequency they don’t.

If you don’t have this crossover facility, you are basically in a position where the sub will be supplementing the bass if the mains rather than taking control.

In this instance, your mains are going to run out of puff way before your sub.


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I just finished going through the owners manual for his integrated amplifier. It has NO H.P. filter for the main speakers when using a subwoofer. IMO, sell your int.amp. an get a AVR. first .
 

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It will take a while to understand what you wrote, but my father is electrician and we will figure it out together.
But i also read on other forums that the rated 1550W at 4 ohms is definietly not RMS. The amp runs better at 8 ohm loads.
I have a bad habit of 'speaking to myself', so it's quite possible that there's simply a better way to explain it. If I had a white board... :) But I think that if you give yourself a little time, it'll start to simplify in your head, and if it doesn't, questions never hurt. FWIW, if the only thing you get out of it is that you can verify actual output levels at the 'nominal' impedance load (4 ohms in this case), and then extrapolate to what that would be with 6 dB steps for every halving and doubling of voltage, it's a useful tool to just guestimate the answer to the question of, "Is my driver actually seeing that kind of signal level, RMS or not?"

Another way to approach it, put a meter on the terminals, play a - 6dBFS 40 Hz test tone on REW through a digital connection (or have REW make you a file, play it on a USB stick on a DVD player or whatever), and then set the gain on the integrated amp or preamp so that the subwoofer amplifier is measuring 20 volts. That corresponds to 100 watts at 4 ohms. That is high continuous output for a little bookshelf speaker, but with an Ultimax it should be cruising, and because you're at 40 Hz, where there is likely an impedance hump, it isn't actually drawing near that power, but that's okay, because what we care about is the amplifier signal level, which is a voltage source, the amperage is incidental. Check out that setting on the gain. At that gain position, the peak level it could possibly generate would be 0 dBFS, or 6 dB higher, or 4 times the power, or 400 watts.

If your volume level is tracked in dB, you can extrapolate from there. 3 dB higher would max at 800 watts. 3 dB lower would max out at 200 watts, 6 dB lower would max out at 100 watts, 9 dB lower would max out at 50 watts, 10 dB lower would max out at 40 watts, etc.

Since i have an integrated amplifier with a sub out i cant pull it up to 100% because then my speakers would die.
Cranking the subwoofer level of the preamplifier output to max on the gain adjustment isn't exactly what I meant. I meant that in an ideal, theoretical world, if you wanted to maximize signal to noise ratio between the interfaces (which is a relatively small detail in the scheme of things) you'd like to set the level on the subwoofer output so that when the main volume control is at the highest setting you'd possibly use (probably clipping the speakers), or clipping the integrated amplifier, even if you intend not to, that the voltage level on the subwoofer preamplifier output is either near (but just below) it's maximum capable output (often 2 volts, but it varies) but also below the maximum input level that can be accepted by the amplifier.

The input sensitivity spec isn't the same thing, and I think I might have confused that. Rather the input sensitivity is the input level that after amplification will correspond to the output voltage corresponding to the rated output of the amplifier (at whatever impedance and power rating they are choosing to reference). When the gain controls are turned all the way up (assuming the amplifier has them, which I think in your case, it does), it simply means that the input sensitivity is in fact what it is specified to be. However, when you turn the gain controls down (and they're pretty much gain attenuators only), that input sensitivity value effectively goes up (because gain goes down, so it takes more voltage on the input to hit maximum output), and it takes more voltage on the input to reach the rated output. With only a quick glance at your amplifier's specifications, it has two input sensitivity settings, so setting the switch to the lower value means that it applies more voltage gain at the same knob position.

I think i'm doing a pretty lousy job, so sorry for that. But from a really basic standpoint, we want the signal levels between components to be as high as we can above the noise floor of both the outputs and the inputs, but not so that that you clip either the outputs, or the inputs, before you actually clip the output of the power amplifier. If the gain controls are basically potentiometers preceding the electronics (and/or A/D converters) then you really don't need to worry about clipping the input section of the amplifier, because you're not going to clip the at the potentiometers, and whatever will clip the inputs beyond that will definitely clip the power amplifiers, unless you're doing a bunch of attenuation in the DSP section, assuming it has one, and I think you said it did.

If your woofers are nice a quiet, and you don't hear noise out of them when no music is playing, this isn't really something to spend a whole lot of energy on. It might make the background level a little quieter, but if you have to put your head against the subwoofer to hear the back ground noise anyway, it could be argued that it truly does not matter. :)
EDIT
Catching up on the rest of the posts, it sounds like your issue is something much more basic and fundamental.

I would first check the subwoofer. With a regular old 9 volt battery applied to the terminals, does it make the cone visibly move? If it doesn't, you might have your coils wired in series, but in opposite polarity, or some other interesting mishap. This would allow current to flow, but the magnetic fields would largely cancel, and very little output, despite a lot of power getting dumped.

You could also put a 'regular' speaker in its place, and playing something in the range that regular speaker could reproduce, or without a filter, check the relative output level.

If you have left/right preamplifier outputs, you can have one on your integrated amp, and then run your subwoofer amp full range, and see how the gain compares.
 

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I just finished going through the owners manual for his integrated amplifier. It has NO H.P. filter for the main speakers when using a subwoofer. IMO, sell your int.amp. an get a AVR. first .
I did the same thing yesterday. That Cambridge unit looks nice and probably does a nice job with 2-channel intentions, but there is virtually no information (and no adjustments possible) regarding the subwoofer output. That will make getting the most out of this sub very difficult.

But with the minidsp that wouldnt be a problem i guess, since i can give it more gain?
Unfortunately, that is not how the entry level MiniDSP's work. They do not provide additional gain in the signal path. They essentially just pass-through the max of what they are given and you can attenuate if needed.
 

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I have a bad habit of 'speaking to myself', so it's quite possible that there's simply a better way to explain it. If I had a white board... :) But I think that if you give yourself a little time, it'll start to simplify in your head, and if it doesn't, questions never hurt. FWIW, if the only thing you get out of it is that you can verify actual output levels at the 'nominal' impedance load (4 ohms in this case), and then extrapolate to what that would be with 6 dB steps for every halving and doubling of voltage, it's a useful tool to just guestimate the answer to the question of, "Is my driver actually seeing that kind of signal level, RMS or not?"

Another way to approach it, put a meter on the terminals, play a - 6dBFS 40 Hz test tone on REW through a digital connection (or have REW make you a file, play it on a USB stick on a DVD player or whatever), and then set the gain on the integrated amp or preamp so that the subwoofer amplifier is measuring 20 volts. That corresponds to 100 watts at 4 ohms. That is high continuous output for a little bookshelf speaker, but with an Ultimax it should be cruising, and because you're at 40 Hz, where there is likely an impedance hump, it isn't actually drawing near that power, but that's okay, because what we care about is the amplifier signal level, which is a voltage source, the amperage is incidental. Check out that setting on the gain. At that gain position, the peak level it could possibly generate would be 0 dBFS, or 6 dB higher, or 4 times the power, or 400 watts.

If your volume level is tracked in dB, you can extrapolate from there. 3 dB higher would max at 800 watts. 3 dB lower would max out at 200 watts, 6 dB lower would max out at 100 watts, 9 dB lower would max out at 50 watts, 10 dB lower would max out at 40 watts, etc.


Cranking the subwoofer level of the preamplifier output to max on the gain adjustment isn't exactly what I meant. I meant that in an ideal, theoretical world, if you wanted to maximize signal to noise ratio between the interfaces (which is a relatively small detail in the scheme of things) you'd like to set the level on the subwoofer output so that when the main volume control is at the highest setting you'd possibly use (probably clipping the speakers), or clipping the integrated amplifier, even if you intend not to, that the voltage level on the subwoofer preamplifier output is either near (but just below) it's maximum capable output (often 2 volts, but it varies) but also below the maximum input level that can be accepted by the amplifier.

The input sensitivity spec isn't the same thing, and I think I might have confused that. Rather the input sensitivity is the input level that after amplification will correspond to the output voltage corresponding to the rated output of the amplifier (at whatever impedance and power rating they are choosing to reference). When the gain controls are turned all the way up (assuming the amplifier has them, which I think in your case, it does), it simply means that the input sensitivity is in fact what it is specified to be. However, when you turn the gain controls down (and they're pretty much gain attenuators only), that input sensitivity value effectively goes up (because gain goes down, so it takes more voltage on the input to hit maximum output), and it takes more voltage on the input to reach the rated output. With only a quick glance at your amplifier's specifications, it has two input sensitivity settings, so setting the switch to the lower value means that it applies more voltage gain at the same knob position.

I think i'm doing a pretty lousy job, so sorry for that. But from a really basic standpoint, we want the signal levels between components to be as high as we can above the noise floor of both the outputs and the inputs, but not so that that you clip either the outputs, or the inputs, before you actually clip the output of the power amplifier. If the gain controls are basically potentiometers preceding the electronics (and/or A/D converters) then you really don't need to worry about clipping the input section of the amplifier, because you're not going to clip the at the potentiometers, and whatever will clip the inputs beyond that will definitely clip the power amplifiers, unless you're doing a bunch of attenuation in the DSP section, assuming it has one, and I think you said it did.

If your woofers are nice a quiet, and you don't hear noise out of them when no music is playing, this isn't really something to spend a whole lot of energy on. It might make the background level a little quieter, but if you have to put your head against the subwoofer to hear the back ground noise anyway, it could be argued that it truly does not matter. :)
EDIT
Catching up on the rest of the posts, it sounds like your issue is something much more basic and fundamental.

I would first check the subwoofer. With a regular old 9 volt battery applied to the terminals, does it make the cone visibly move? If it doesn't, you might have your coils wired in series, but in opposite polarity, or some other interesting mishap. This would allow current to flow, but the magnetic fields would largely cancel, and very little output, despite a lot of power getting dumped.

You could also put a 'regular' speaker in its place, and playing something in the range that regular speaker could reproduce, or without a filter, check the relative output level.

If you have left/right preamplifier outputs, you can have one on your integrated amp, and then run your subwoofer amp full range, and see how the gain compares.
It does have L & R pre-amp puts, but NO high-pass filter for the main speakers so he should run some tower speakers like the Klipsch RP-280F's ($400 ea. At Crutchfield) for his main speakers if he plans to stick with his integrated amplifier; not any bookshelf speakers.
 

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At the end of the day he can’t get around the issue that with the Cambridge there is no way of making the mains life easier.

In this type of system, the subwoofer should be set at the lowest low pass you can get away with. I would say 60hz with those bookshelf’s

And then it’s just used to add the lower end and give more bass. At below 60hz

A 2 way speaker with a sub. Instead of turning a 2 way in to a 3 way which is what most want to do. But the Cambridge can’t.

In fact for such an expensive integrated amp I think it’s terrible. Giving you a sub output but not having anything to make it work properly.

I would sell it and get a minidsp SHD power and be done with it all. It will go much louder and cleaner and it has a better dac plus room correction. All for more or less same money


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How did you determine the amp is clipping? Ive seen posts like this before with OP believing the amp was clipping on account of misinterpreting the signal level indicator. Did you read the manual?

Did you wire the woofer coils right and did you wire the woofer to amp right for bridge mode?

Assuming the amp spec is anywhere close to true it should do at least 75V, more than plenty for you woofer.
 

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It does have L & R pre-amp puts, but NO high-pass filter for the main speakers so he should run some tower speakers like the Klipsch RP-280F's ($400 ea. At Crutchfield) for his main speakers if he plans to stick with his integrated amplifier; not any bookshelf speakers.
In my opinion, I would take one step farther, and say that if as far as my own preferences, if a setup doesn't allow an actual full crossover with a subwoofer, I'd look to simply replace it with something that does, preferably with high-pass options that I can use to not only select frequency, but also slope as well as contour of slope, or apply contouring of the low frequency limits of the main speakers to maximize the splice. But that's just me.

Yes, you can take the route of letting the mains run full range, and it may work reasonably well (or it may not) but it not only leaves half of the benefits of an active crossover between the subwoofer and the main speakers in the trash, but it may become more difficult, or even impossible, to get believable coherent integration.

But if he is simply looking to get his sub to play along with his bookshelf speakers as they are, and is willing to accept the limitations of that, the first issue seems to be one of either signal level to the amplifier, or the amplifier itself failing to provide the voltage level to the speaker, and if all of that is working fine and he cannot get some substantial cone movement and the amplifier is actually triggering the clipping indicators, and functioning, something may be either wrong with the driver or the wiring, and he needs to check it systematically from one end until the other until he can nail down what's wrong, and the rest of us can offer helpful suggestions, but all is speculation until data is collected.

On the woofer itself, If he has a meter, (and I think it's good to have anyway), test the terminals. If it has dual 2 ohm coils, the DC series resistance should be near 4 ohms, but probably not spot on, but so long as it isn't closer to 2, or 1, it is probably wired in series.

The other thing is to verify that the coils are wired in correct polarity + to - to + to -. With a 9 volt battery, + on the + terminal at the woofer (or on the speaker cable), the woofer should move appreciably forward (and stay forward while connected) and have a low level thump. With reverse polarity, it should move appreciably backwards. If all that happens is a small pop and almost no movement, it may be that the coils are wired in series, but in opposite polarity (or the terminals and coil polarity has an error in manufacturing). If one coil is wired in series with itself (shorted), and the other coil connected, you've essentially made a transformer hanging off the first voice coil acting as a primary, and then shunting a lot of that power that will be simply burned up on the second coil. I've never actually tried that, and it's a bad idea, but I would think that would significantly lower output. I have heard of doing this with a resistor on the second coil for additional electrical damping, but no resistor means maximum damping which means maximum energy draw away from the actual function of the motor.

IF you can move the cone with a 9 volt battery, maybe a 1/4 inch or something like that, maybe a little less, but most definitively, and it most definitively changes direction with polarity, it should move at least somewhat to generate appreciable output with a functional amplifier, even if it's only a few hundred watts. When I was doing free-air testing, at any frequency below resonance, while there were minor differences, at about 20 volts RMS, from 8 Hz to the mid 20 Hz, peak to peak movement was near an inch. Air volume will obviously constrain that, but point being, that constraint will be the same with any driver, and even my drivers, which were off spec significantly and had a significantly stiffer suspension, the driver itself was not exceptionally difficult to push to excursion in itself. If the OP wants to take the driver out of the enclosure for testing purposes, he can bypass the internal air pressure, just in case.

If the driver seems to be behaving, putting a little bookshelf speaker, sans filtering, and starting at low levels, is a way to check relative level without the need for a meter, but myself, I'd like to know specifically, and a voltage meter is not a difficult tool to use, and you can generate test tones with REW, or use an app on your phone even, or download them if necessary. You can also get a headphone adapter and drive the amplifier, for diagnostic purposes, directly from the phone, as I think most of them should be able to drive that amplifier to clipping with the high sensitivity setting and the gain controls all the way up.

But, in short, I agree that the setup is not optimal for making the most out of a subwoofer if it doesn't have the means to use a high pass, but if the amplifier is actually indicating clipping, and he's not getting much of any output out of the woofer (and I guess he could take it outside to test it to remove the room from the equation, or put his head or a meter or a microphone right next to it), he's going something going on that he probably needs to iron out, no matter what.

I am eagerly awaiting his reports of discovery.
 

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If you want to be able to play the stuff you have louder, the solution is simple.

1: Turn bass control down on the Cambridge. Main speakers somewhat relieved from bass duty.
2: Mini dsp between Cambridge and the sub to re-equalize the lack of bass + do room control + any gain mismatch you may/may not have.

Yeah, there are better ways to do it, but if you use a mic and REW you should be able to figure it out and make it pretty damned good -just the bass control center freq is not within your control, so make it work the best you can with the hardware you have.
 

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cambridge audio cxa81 seen don't have Line out
i see always Pre out very low signal need cxa81 more volume to get more too loud subwoofer look bad

mine onkyo a-9070 seen problem Pre out sub connected dayton plate amp 250watts but i did volume knob for onkyo i was set -20dB but subwoofer not much too loud look weak bass and need more onkyo volume knob -10dB also not much too loud just abit more bass sound sub very bad i did try 0dB got too loud bass subwoofer but Front speaker bookshelf over over crank loud crazy too bad so i off onkyo then i unplug Pre out then i connect Line Out Fixed then i turn on onkyo i set volume knov -20dB wow Subwoofer got too loud yay i did try volume knob -30dB lower but subwoofer wont be change volume level look fixed mean will stay too loud so i set gain plate amp 1 o clock fell too loud if volume knob onkyo set -10dB but subwoofer wont go above volume due its Fixed level for Line out just need adjust plate amp gain

but you cambridge audio cxa81 don't have Line Out fixed look bad

i will use Line Out fixed for subwoofer then you can set any gain level enough bass too loud
if you want volume down then need gain adjust knob level down that is all
 

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That is interesting. I've never had a unit (that wasn't broken) with preamplifier outputs that couldn't output enough to have the subwoofer match. It could certainly serve as a method to compare relative signal levels, though I would turn the gain controls all the way down before trying to play anything.

If you're okay with adjusting the volume twice, all the time, and having the balance a little different every time, using a fixed line level output can do the trick. The last time I had multiple volume controls, it was because I was daisy-chaining audio systems and boom boxes to see how much sound I could get into my bedroom at my parents' house. We were also able to accidentally tune in some radio broadcasts with that setup. That was kind of fun. Big wall of messy sloppy glorious sound.

My parents were very patient. Before I moved out, I had some Klipsch Forte II's, and a big bass null in the center of my room, and in my quest to get bass, I kept turning it up. Bass was all around the sides of the room, but not where I could sit and get imaging. In my parents' adjacent bathroom, things were vibrating off of shelves and falling on the ground, and eventually my mom let me know that the bass was working really well, and asked me to stop.

First clear introduction to room modes, standing waves, and why a subwoofer, even one less capable in output than the left/right, can be useful. A dinky little M&K Dual 8" MX-70, located at the front center of the room, elevated on top of a small desk, probably centered about 3 1/2 or 4 feet, got me bass where I sat. It didn't have near the output of a couple of 12's with 15" passive radiators, but it didn't need to, at least to get me a whole lot more than I was getting.
 

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My thoughts are that he isn't actually clipping the Crown amplifier, but the speakers are distorting when he turns the volume up to get more bass. Since those work in tandem, and there is no option to individually control the bass output, that is my conclusion. The Crown will arguably put out around 1100-1200W RMS when driven on the ragged edge of clipping in bridged 4Ohm mode. Since impedance varies with frequency, and the UM12 isn't really a true 2Ohm per coil, maybe it would only put out 800-900W. Regardless, that much power should be rocking that cone. Whether or not that is 'loud' bass depends on your personal taste, but it really should be decent for those Klipsch speakers. By personal taste I mean, with (2) 15s and (2) 21s and bass-centric music, I bump my sub outs and probably run close to 30dB hot compared to the mains. With movies I run them 15dB hot. So no, he won't be at those levels, but the output should not be 'weak'.

Back to the OP's issue. He has not verified that he is indeed seeing the red clip light at the top of the Crown light tree. I don't honestly think he is clipping the Crown's outputs. If he decides to go the MiniDSP route, I would suggest the 2x4HD. It has the ability to boost the line level gain, and it works quite well as I can attest. Barring the MiniDSP, the cheaper suggestion would be getting an ART Cleanbox Pro. The CB Pro can bump the line level to extreme levels.

I really think this boils down to the typical 'My Crown amplifier seems weak' issue, and either a MiniDSP 2x4HD or a CB Pro will solve it.

If I am incorrect, and the Crown actually is lighting up the red clip indicator, then it is something else, and I apologize.

OP, please let us know if you are actually seeing the red clip indicator light on the crown output light tree. It is the top light in the two light columns on the front of the amp next to the Gain Attenuation knobs.
 
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