Cheapest way to incorporate High Pass filter?

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Sub/Amp setup consists of:

(1) Lab 12 tapped horn (about 25hz tuning or so)
(2) Tang band 6.5" Double fold 38hz tapped horns

QSC rmx 1450 bridged to power the big lab 12 horn
Denon DSW-40 plate amp to powe the small horns (wired in series, 8.2 ohm Re)

I have an 80hz low pass built in to my receiver, sending that signal to both subs.

I have no high pass filter on the QSC amp (only 30 or 50hz selectable) and no high pass on the denon plate amp (i figure it has a built in high pass, probably way too low, and i have no idea what it is)

I think one of the motors on one of my Tang band subs is messed up, it makes some noise at 42hz and below (tuning was supposed to be 38hz). Above 45hz the mini horns make plenty of clean bass, no motor noise.

So, my question. I really need a high pass on the mini horns for noise purposes (I'm not buying a new tang band sub at $100 a pop, price has sky rocketed) and i should really have a high pass on the big sub for safety purposes (400RMS rated driver, getting about 1000rms clean power or so)

I thought about passive, but the components are kinda pricey to handle the wattage, and i would need two.

Would mini DSP's do? I've never used them, but maybe this is a good time to try them out...

any other ideas? thanks guys!
 
^have you used those? are they any good? do they eat up a lot of signal voltage?

I would need the pair of 20hz for the QSC amp, and a pair of 45HZ for the denon amp....that would be around $50 or so....hmm, worth it to buy those, or spend the $100 now, only 50 more, and get a DSP which i can change slopes etc whenever....ahh decisions decisions!

from their site...
"Fixed crossover point (-3db) high pass (passes high frequencies such as mid/tweet amplifier use) passive crossover modules. The RCA plug is the output and "points" toward the amplifier. These may be combined to produce 24db per octave slopes if a 3db attenuator is used between them. Keep in mind that two equal value FMOD high pass modules will increase the slope to 24db per octave and the crossover point will be double the FMOD value. Two 100 high pass FMODs with the 3db attenuator between them will become a 200 high pass 24db per octave crossover. This also holds true for combining FMODS with other equipment to alter the crossover point(s) and to increase the slope AND in that case you do not need the 3db attenuator. When ordering be sure to select the crossover point from the drop-down list. Passive device so there is no noise or distortion (transparent to your system). Color coded for crossover point."

so the slope, with one FMOD per channel is only 3db/octave? i dont think that would be steep enough for my needs...
 
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^have you used those? are they any good? do they eat up a lot of signal voltage?

I would need the pair of 20hz for the QSC amp, and a pair of 45HZ for the denon amp....that would be around $50 or so....hmm, worth it to buy those, or spend the $100 now, only 50 more, and get a DSP which i can change slopes etc whenever....ahh decisions decisions!

from their site...
"Fixed crossover point (-3db) high pass (passes high frequencies such as mid/tweet amplifier use) passive crossover modules. The RCA plug is the output and "points" toward the amplifier. These may be combined to produce 24db per octave slopes if a 3db attenuator is used between them. Keep in mind that two equal value FMOD high pass modules will increase the slope to 24db per octave and the crossover point will be double the FMOD value. Two 100 high pass FMODs with the 3db attenuator between them will become a 200 high pass 24db per octave crossover. This also holds true for combining FMODS with other equipment to alter the crossover point(s) and to increase the slope AND in that case you do not need the 3db attenuator. When ordering be sure to select the crossover point from the drop-down list. Passive device so there is no noise or distortion (transparent to your system). Color coded for crossover point."

so the slope, with one FMOD per channel is only 3db/octave? i dont think that would be steep enough for my needs...
You are an experimenter, this won't be your last set up, get some DSP that allows multiple configurations without spending multiple $$.
 
Okay so is that one I linked to the best option? $100 2 in 4 out, that should be able to control both subs seperately right? Aka I can set one slope / high pass on one input Channel and a different slope / high pass on Another?

Reason I'm being cheap about this is because it's all for my patents HT, and 90% of the time my mom is home and bitches if we have the subs on. Sooo all this $ I've spent on the sub setup which I can only use 10% of the time without hearing complaints lol. So it's WAF for my dad, and MAF (mom acceptance factor) for me :/
 
I feel your pain

I built a sub for the HT system that will shake the house etc and works very well. The downside is my wife figured out how to shut the sub off so it high passes to the mains at 80Hz--I built a sub to be used as a bass filter? :confused:

The sub does get used for movies so is not gathering dust. Figured the way to solve the problem was build a system in the garage, no problems there.

With the mini DSP...slip it a little bit of bass here and there to see what you can get away with? 60Hz should get you some drums in there so it won't be too bad.
 
I know it sucks. And my house is old so the entire f'in thing shakes Nice thing about the separate sub amps and high passed mains/surrounds is that there is almost NO bass without the subs on. Of course I think it sounds terrible, but my mom loves it lol
My guess is you are probably setting the sub level about 10 or more dB hotter than the mains.
I have not met a woman yet that does not like low frequency, but have also not met one that likes LF to feel like a cavity search.
You may consider balancing the sub level to the mains at the crossover point, your mom probably won't mind extended lows if they are balanced.

By balancing the level at the crossover, you will be hearing the program material as it was mixed (for the most part) rather than a cartoon version that just aggravates anyone who dislikes gross exaggeration.
Pano recently made some test tones that would be a help to balance subs to tops.

http://www.diyaudio.com/forums/atta...321408737-localizing-bass-rumble_pingpong.zip
Art
 
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I don't think so art..I used the level cal on my receiver to set everything (I know that gain on the sub amp is directly related to this as well)
The sub level matches the mains unless I turn it up (which makes it sound boomy and exaggerated like you described)
My mom is just over sensitive to stuff (or just likes to bitch because she feels like it?) like smells, bass etc lol
 
I don't think so art..I used the level cal on my receiver to set everything (I know that gain on the sub amp is directly related to this as well)
The sub level matches the mains unless I turn it up (which makes it sound boomy and exaggerated like you described)
My mom is just over sensitive to stuff (or just likes to bitch because she feels like it?) like smells, bass etc lol
Your mom may like to bitch, but my bet still is the subs are not level matched to the mains.

Level cal is a full range signal (at least it is on my Technics receiver), your ear is less sensitive to LF so you will tend to set LF higher than the main speakers as in an equal loudness contour.

if your crossover is around 80, try the 80 pingpong tone with only mains, then only subs, and see if the level is matched. Use a dB meter, or a recorder with a VU meter if you don't have a dB meter or test gear.
 
You could be right. My Ears may not be trained. What I meant by matched was the sub doesn't overpower the mains or surrounds. Gain on the qsc is halfway up, and on level cal the subs are at +6db. Mains (which are 92db 1w/1m) are set at +10db.
So when scrolling through each channel and listening to the static standing in the center of the room, the sub channel does seem a lot quieter than the others. (actually much quieter as you can hear the cooling fan I have set up on top of the receiver)

But I haven't used any mics to calibrate, I never got the auddessy mic when I purchased my receiver.
 
You could be right. My Ears may not be trained. What I meant by matched was the sub doesn't overpower the mains or surrounds. Gain on the qsc is halfway up, and on level cal the subs are at +6db. Mains (which are 92db 1w/1m) are set at +10db.
So when scrolling through each channel and listening to the static standing in the center of the room, the sub channel does seem a lot quieter than the others. (actually much quieter as you can hear the cooling fan I have set up on top of the receiver)

But I haven't used any mics to calibrate, I never got the auddessy mic when I purchased my receiver.
The level settings you mention are like saying the gas pedal is halfway down instead of saying the car is going 50 MPH ;^).

Even without any test gear, Pano's 80Hz pingpong tone will make it easier to align the levels. Listen in some different parts of the room and with the different tones to start training your ears.
 
Cheaper than Cheap

Hi, if you Really want to do it as Low $ as possible, then i reckon you could for Under $10 :) And that includes a nice little box to mount the components in ;)

The Att. screenie shows one one channel, but would be duplicated for Left & Right. Mono summing could very easily incorporated as well if required for just a single Sub.

If you're interested just holla & i'll work out the component values for you.
 

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It's not that i'm bored ! just thought i'd do it as a favour ;)

Won't hurt at all :)

This filter will be 12dB/Octave. Is that OK ?

1 - Let me know the output impedance of your PreAmp.

2 - Let me know the input impedance of your Amps.

3 - Please confirm that both the Lab 12 & TBTH's are Mono powered.
 
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