LPF on subwoofer - what level when calibrating by ear?

[olds1959special]

I am finding I like my subwoofers set to around 80 Hz even though my main speakers go much lower. I’m not using a crossover. It seems to make sense to get as much range out of the subwoofer without creating muddiness from too many overlapping frequencies. Is there a way to do this or is just to taste? I haven’t tried measuring yet (I’m saving up for a Umik.)

 

[EERecordist]

I would look at a Spinorama of your main speakers of they have been testes - spinorama.org or ASR, then plan your crossover frequency and slope from that. Then when you get your Umik and software setup, you can refine it. Until then by ear, and people usually like extra bass anyway.

 

[DVDdoug]

You can't really "calibrate" by ear so you'll have to adjust "to taste" and you're somewhat limited without a crossover. I suspect you like some bass boost if your main speakers "go lower" and you like the sub mixed-in.

It's normal to prefer bass boost when you're not listening loud because the Equal Loudness Curves make it sound like we've turned-down the bass when we turn down the volume.

(I’m saving up for a Umik.)

There's only so-much you can do without a crossover and EQ, except you can try re-positioning the woofer to see how that changes the measurements. And then what? ...Are you going to adjust it to measure good, or the way you like it? Measurement is good if you want to identify and correct room problems with EQ and/or acoustic treatment.

 

[SHB]

You didn’t give any info on your speakers, but a great rule of thumb for setting up a subwoofer with the main speakers is to cross them over one octave above where the mains run out of steam.

If their -3dB point is 50Hz, set the crossover to 100Hz.

Also, if you have any measurement data on the speakers, look at the plots of the speakers low bass THD measurements. There will generally be a corner frequency where the distortion goes from fairly flat to steeply upward with decreasing frequency. That frequency will be the best for optimizing your system to get the least distortion.

Having your subs and your mains run at the same time when the mains are mostly producing distortion at their lowest frequencies will not give you the best sound. Also, having less low end rattling your mains will give you cleaner midrange since the cabinets will have less energy from the woofers trying to resonate the cabinets.

This allows you to place your subwoofers independently of where your main speakers sound best. You can then place them in the room where they give you the best response at your listening position.

One last thing: in a properly treated listening room, you can hear stereo down to low B (31 Hz) and possibly lower. If you have two subwoofers, try using them in stereo.

Under any circumstances, hopefully, you have some way to adjust any temporal differences between the mains and the subs. Additionally, sometimes you can get a smoother crossover by delaying the main speakers an extra millisecond or three from “perfect” alignment with the subs. That’s something you have to fiddle with by ear.

 

[boxerfan88]

I am finding I like my subwoofers set to around 80 Hz even though my main speakers go much lower. I’m not using a crossover. It seems to make sense to get as much range out of the subwoofer without creating muddiness from too many overlapping frequencies. Is there a way to do this or is just to taste? I haven’t tried measuring yet (I’m saving up for a Umik.)

While saving for a UMIK, maybe try using a phone audio app that can display frequency spectrum.
Play pink noise as signal, with your phone at your listening position, observe your phone audio app.
Get someone to help adjust the subwoofer volume until the bass is slightly higher than the midrange (roughly a gentle slope down from bass to treble).
Of course, if you really like bass, then push it to your preferred level.
Hope this helps you get started while saving up for UMIK.

(If you need pink noise file, just ask. Many of us here can generate for you.)
/

 

[olds1959special]

I am using stereo subwoofers, with my Vandersteen 2Ce Sig2’s. I have looked at the measurements for these speakers on spinorama and stereophile and have measured myself but I don’t really think they have a flat response. I’m basically aiming for a smiley face eq with this setup and I like bass, so I boost the tweeter and midrange contour controls, and am trying both subs with the gain on ‘2’ although I was previously being conservative and had them set to ‘1’. I tried 80 Hz but it was too high so I lowered to 60 which seems like a good compromise between mixing frequencies and hearing the range of the subs. It seems easier to experiment and determine what works by ear, but I would like to measure later too. Right now I have a cheap Behringer measurement mic, which gives different results from phone (which is right?) I have been experimenting with my other (single) subwoofer setup with ELAC DBR62’s too and I think I dialed it in the way I like it with the LPF set at around 80 Hz, as 100 seemed too high.

 

[suttondesign]

I think it’s important to high-pass your mains, even if fairly low, so that you are free to maximize the spl they can do cleanly. I have mains which are clean to 30hz, but they become distortion machines below that (bc they are open baffle, but the point holds). I run custom subs crossed at 50hz, and they fill in the lowest octave without any strain.

 

[olds1959special]

I think it’s important to high-pass your mains, even if fairly low, so that you are free to maximize the spl they can do cleanly. I have mains which are clean to 30hz, but they become distortion machines below that (bc they are open baffle, but the point holds). I run custom subs crossed at 50hz, and they fill in the lowest octave without any strain.

Not sure how to do that easily.

 

[SHB]

Does your system have a way to hook up subs and run a high pass filter on your mains? You need to look into that.

 

[olds1959special]

Does your system have a way to hook up subs and run a high pass filter on your mains? You need to look into that.

No, I use rca splitters and the sub has no crossover w ins/outs

 

[suttondesign]

parts express has ready-made 80hz high pass filters for cheap.

 

[SHB]

My suggestion is this: do a lot of research using any of the popular AI platforms. Be precise about your system and what you are trying to do in your queries.

Ask a lot of questions and, then, ask the same questions to a different AI. Compare and ask more questions.

Learn everything you can and ask more questions of more than one AI.

You will get more valid and intelligent information from ChatGPT, Grok, etc. about audio than you will from people who post to this site.

Lastly, demand that the AI be concise and precise or it will give you the history of the universe.

 

[boxerfan88]

I tried 80 Hz but it was too high so I lowered to 60 which seems like a good compromise between mixing frequencies and hearing the range of the subs.

Crossover in the 60-80 range is okay.

Right now I have a cheap Behringer measurement mic, which gives different results from phone (which is right?)

For the time being, doesn't really matter which is right. That is until you buy the calibrated UMIK.
For now just shoot for downward slope from bass to treble. The amount of bass boost is really up to your preference. If you like smiley, then smiley it is.


As mentioned by others, HPF the mains is highly recommended as it can reduce the distortion in the midrange area by relieving the woofer from having to perform large excursions. If you cannot do HPF, don't sweat it, just enjoy your system.

/

 

[MediumRare]

parts express has ready-made 80hz high pass filters for cheap.

Both 8 and 4 ohm are backordered. How to choose which one? How to set up? Any way to know what the effect on SQ is? (Noise, distortion, etc.) https://www.parts-express.com/80-Hz-High-Pass-4-Ohm-Crossover-266-456

 

[SHB]

Dude, you have not offered enough information for anyone at this portal to give you really good, qualified information about how you should proceed forward.

Also, I wouldn’t take anything that you read here with more than a grain of salt.

At the moment, you’re flailing. Stop it.

Hit up one or more of the available free, AI portals to get valid information cleaned from a gigantic number of sources.

In a previous post, I told you how to do this to get your best result. i’m done with this thread.

 

[olds1959special]

Dude, you have not offered enough information for anyone at this portal to give you really good, qualified information about how you should proceed forward.

Also, I wouldn’t take anything that you read here with more than a grain of salt.

At the moment, you’re flailing. Stop it.

Hit up one or more of the available free, AI portals to get valid information cleaned from a gigantic number of sources.

In a previous post, I told you how to do this to get your best result. i’m done with this thread.

AI can be a bit hit or miss in terms of being accurate and helpful, I think.

You didn’t give any info on your speakers, but a great rule of thumb for setting up a subwoofer with the main speakers is to cross them over one octave above where the mains run out of steam.

If their -3dB point is 50Hz, set the crossover to 100Hz.

Also, if you have any measurement data on the speakers, look at the plots of the speakers low bass THD measurements. There will generally be a corner frequency where the distortion goes from fairly flat to steeply upward with decreasing frequency. That frequency will be the best for optimizing your system to get the least distortion.

Having your subs and your mains run at the same time when the mains are mostly producing distortion at their lowest frequencies will not give you the best sound. Also, having less low end rattling your mains will give you cleaner midrange since the cabinets will have less energy from the woofers trying to resonate the cabinets.

This allows you to place your subwoofers independently of where your main speakers sound best. You can then place them in the room where they give you the best response at your listening position.

One last thing: in a properly treated listening room, you can hear stereo down to low B (31 Hz) and possibly lower. If you have two subwoofers, try using them in stereo.

Under any circumstances, hopefully, you have some way to adjust any temporal differences between the mains and the subs. Additionally, sometimes you can get a smoother crossover by delaying the main speakers an extra millisecond or three from “perfect” alignment with the subs. That’s something you have to fiddle with by ear.

Vandersteen 2Ce Sig II's. This is for the 2C from Spinorama:

Again, 60 Hz is working pretty well for me with these speakers. You can see they start to roll off around 50-60 Hz.

 

[olds1959special]

You can't really "calibrate" by ear so you'll have to adjust "to taste" and you're somewhat limited without a crossover. I suspect you like some bass boost if your main speakers "go lower" and you like the sub mixed-in.

It's normal to prefer bass boost when you're not listening loud because the Equal Loudness Curves make it sound like we've turned-down the bass when we turn down the volume.


There's only so-much you can do without a crossover and EQ, except you can try re-positioning the woofer to see how that changes the measurements. And then what? ...Are you going to adjust it to measure good, or the way you like it? Measurement is good if you want to identify and correct room problems with EQ and/or acoustic treatment.

Yes, you're right, I think I like the bass boost. I'm not listening at super loud levels all the time. And especially since I max out the tweeter contour control (+2dB) and add +0.5dB with the midrange control.