What would be your recommendations for how to integrate subs and mains in this scenario.
I have a miniDSP 2X4 HD
I have two REL Strata III subs, and a pair of Reference 3A Dulcet speakers:
6moons audio reviews: Reference 3A Dulcet
Subs are located 30 inches away, and 45 degrees behind and towards the center of each main. (See sketch)
Attached are a few measurements. I took three measurements and averaged them for the sake of this post. I used VAR smoothing, which seems to keep the LF pretty detailed, while smoothing the higher frequencies. Subs and mains measurements are taken raw, with no crossover or filters on the subs or in dsp. Obviously the blue is the sub and the purple are the mains. Subs are cranked up way too high obviously, but I can turn those down in software or with the dial. The question is about approach. Nothing is dialed in at all right now.
- Recommended crossover points.
- What to do about nodes etc? The peaks in the LF appear to be at 45, 80, 112, and 155 Hz.
- Do I knock those down with PEQ first, before applying the crossovers?
I have a miniDSP 2X4 HD
I have two REL Strata III subs, and a pair of Reference 3A Dulcet speakers:
6moons audio reviews: Reference 3A Dulcet
Subs are located 30 inches away, and 45 degrees behind and towards the center of each main. (See sketch)
Attached are a few measurements. I took three measurements and averaged them for the sake of this post. I used VAR smoothing, which seems to keep the LF pretty detailed, while smoothing the higher frequencies. Subs and mains measurements are taken raw, with no crossover or filters on the subs or in dsp. Obviously the blue is the sub and the purple are the mains. Subs are cranked up way too high obviously, but I can turn those down in software or with the dial. The question is about approach. Nothing is dialed in at all right now.
Last edited:
Looking at your frequency plot, I'm guessing the subs are blue and your mains are red (at least that would make sense).
First, what is your goal?
Are you looking for good solid bass that integrates well with a wide range of music or are you perhaps looking for some artificial bass boost? (Neither is wrong, but it does change the advice)
Generally the goal in integrating subs into a system is to make up for a lacking low end in the remainder of your system. You want the sub boxes to cut in at about the point where your mains and satellites get weak... generally around 110hz for bookshelves and 80hz for floorstanders... although each setup is different.
You don't actually want to hear the subs as a distinct entity in your room, the levels should be set so that you aren't consciously aware of the switch between sub and mains, but when there is very deep bass on hand they handle it for you.
Alternatively if you're looking to take a butt kicking while watching a movie or listening to techno or rap, just turn the sub boxes up to your own satisfaction. (But don't expect it to sound right for Rock, Jazz or Classical music)
The first thing to take a look at is the response from your mains ...
They get down practically as far as your sub boxes do. You might find the subs to be unnecessary, with just a bit of EQ applied to your mains. In fact, this happens more often than you might think. On stereo systems, a lot of the subs out there either have their crossovers up so high that you hear them as distinct speakers or they sit silent 90% of the time.
From your image, I would suggest you cross over at the bog standard 80hz, adjust the levels to a seamless blend with your mains, then listen for a few days before you do much tweaking.
First, what is your goal?
Are you looking for good solid bass that integrates well with a wide range of music or are you perhaps looking for some artificial bass boost? (Neither is wrong, but it does change the advice)
Generally the goal in integrating subs into a system is to make up for a lacking low end in the remainder of your system. You want the sub boxes to cut in at about the point where your mains and satellites get weak... generally around 110hz for bookshelves and 80hz for floorstanders... although each setup is different.
You don't actually want to hear the subs as a distinct entity in your room, the levels should be set so that you aren't consciously aware of the switch between sub and mains, but when there is very deep bass on hand they handle it for you.
Alternatively if you're looking to take a butt kicking while watching a movie or listening to techno or rap, just turn the sub boxes up to your own satisfaction. (But don't expect it to sound right for Rock, Jazz or Classical music)
The first thing to take a look at is the response from your mains ...
They get down practically as far as your sub boxes do. You might find the subs to be unnecessary, with just a bit of EQ applied to your mains. In fact, this happens more often than you might think. On stereo systems, a lot of the subs out there either have their crossovers up so high that you hear them as distinct speakers or they sit silent 90% of the time.
From your image, I would suggest you cross over at the bog standard 80hz, adjust the levels to a seamless blend with your mains, then listen for a few days before you do much tweaking.
Are these measurements of both mains and subs or just one?
What seems obvious to me as that both seem to be running into much the same modes at 100 Hz and below. Some more creativity in positioning may be required to even things out a bit more. You can always pull down peaks but bringing up nulls would amount to a substantial increase in power, so you want to be filling those in as well as you can, which means exciting some different modes.
Have you played with REW's room simulation yet? That may help determine some better positions, as well as give you some ideas in terms of delays and crossover and level settings.
What seems obvious to me as that both seem to be running into much the same modes at 100 Hz and below. Some more creativity in positioning may be required to even things out a bit more. You can always pull down peaks but bringing up nulls would amount to a substantial increase in power, so you want to be filling those in as well as you can, which means exciting some different modes.
Have you played with REW's room simulation yet? That may help determine some better positions, as well as give you some ideas in terms of delays and crossover and level settings.
Sorry, I should have mentioned, that is just the left main and left sub. But the right one also has similar nodes.
I haven't gotten into REW room simulations yet, but I don't have a lot of places to reposition with my setup.
All the theoretical info about crossing over at X frequency etc, doesn't quite address how to handle the room peaks. I tried the auto EQ but it didn't quite well.
I'm thinking to first just pull down the peaks, then do a 48db crossover between the sub and mains around 100 Hz. Then remeasure and then do another tweak or two.
But there's that node at 112Hz, so that complicates it a bit.
Maybe it would be better to cross around 150?
I haven't gotten into REW room simulations yet, but I don't have a lot of places to reposition with my setup.
All the theoretical info about crossing over at X frequency etc, doesn't quite address how to handle the room peaks. I tried the auto EQ but it didn't quite well.
I'm thinking to first just pull down the peaks, then do a 48db crossover between the sub and mains around 100 Hz. Then remeasure and then do another tweak or two.
But there's that node at 112Hz, so that complicates it a bit.
Maybe it would be better to cross around 150?
Here is a method: Multiple Small Subs - Geddes Approach
No high pass on the mains. Subs at "random" positions, some eq and level adjustment while measuring. The goal is to make the room modes average out and less of a problem, which are very difficult to handle otherwise. This seems to be the most robust method for any small room, at least what I've gathered from the forums. Have fun!🙂
No high pass on the mains. Subs at "random" positions, some eq and level adjustment while measuring. The goal is to make the room modes average out and less of a problem, which are very difficult to handle otherwise. This seems to be the most robust method for any small room, at least what I've gathered from the forums. Have fun!🙂
Last edited:
Agreed, don't cross the mains if you can help it.
The Geddes thread has info for this procedure. It's long, but educational.
It almost seems inclined to suggest rolling them a little effective above 100Hz and flip the polarity.. but this is probably oversimplifying things.
The Geddes thread has info for this procedure. It's long, but educational.
If power handling isn't a huge concern, I'd be looking to bring the subs in below the 45Hz peak, to fill in the VLF.
Use the MiniDSP to knock down the peaks (assuming they apply at all listening positions), and maybe that 1-2kHz bump, and away you go.
The large ~65Hz notch on the sub output would make me hesitate before using them further up.
Chris
Use the MiniDSP to knock down the peaks (assuming they apply at all listening positions), and maybe that 1-2kHz bump, and away you go.
The large ~65Hz notch on the sub output would make me hesitate before using them further up.
Chris
Thanks for all the responses. I know you guys are trying to get me to drag the subs all over the place lol. I might cave but will give a good fight just trying eq the f out of it. It’s a fun interesting journey. Right now I’m crossed at 95 hz, at 48 dB/octave with the peaks in the LF mashed to pieces. I’ll try that for a bit, then might go back to non-LF passed mains with augmented bass from the subs, moving them into the kitchen and 4ft up the living room wall lol. Will report back
Who Me??? I wouldn't do that 🙄
Good luck with the setup. Improving a system is a journey, not an event.
Not claiming to be an expert, but you asked for it:
First, I'd do near-field measurements of both the subs and the mains to get some idea of what they are actually doing without the room interference. I'd measure each at a loud listening level and look at distortion, especially in the mains. That will tell you something about how low you can actually expect them to cross them. Those are fairly small woofers, I would expect them to appreciate being high-passed to relieve them of some excursion. Even a shallow slope should usefully reduce excursion and distortion. Measurement can confirm that the mains are playing cleanly. Dr. Geddes doesn't high-pass his mains, but he uses much larger and probably more abuse-tolerant pro drivers.
Second (if possible) would be to put one sub at the listening position and measure the response at various potential locations for the sub around the room. See if you can find two locations that have complimentary peaks and dips, and place the subs there. If you can't move the subs the REW room simulator might be a way to get some ideas. My best guess would be one near a front corner, the other midway down a side wall. At some point you'll have to bow to practicality and put the subs where they can fit.
Then, remeasure the bass with both subs active. Take measurements around the listening positions(s) and average them. Knock down the worst couple of peaks with PEQ's, don't worry too much about narrow dips. Match the levels to the mains and adjust the low passes to try to get a good blend. Listen, remeasure, tweak to taste.
First, I'd do near-field measurements of both the subs and the mains to get some idea of what they are actually doing without the room interference. I'd measure each at a loud listening level and look at distortion, especially in the mains. That will tell you something about how low you can actually expect them to cross them. Those are fairly small woofers, I would expect them to appreciate being high-passed to relieve them of some excursion. Even a shallow slope should usefully reduce excursion and distortion. Measurement can confirm that the mains are playing cleanly. Dr. Geddes doesn't high-pass his mains, but he uses much larger and probably more abuse-tolerant pro drivers.
Second (if possible) would be to put one sub at the listening position and measure the response at various potential locations for the sub around the room. See if you can find two locations that have complimentary peaks and dips, and place the subs there. If you can't move the subs the REW room simulator might be a way to get some ideas. My best guess would be one near a front corner, the other midway down a side wall. At some point you'll have to bow to practicality and put the subs where they can fit.
Then, remeasure the bass with both subs active. Take measurements around the listening positions(s) and average them. Knock down the worst couple of peaks with PEQ's, don't worry too much about narrow dips. Match the levels to the mains and adjust the low passes to try to get a good blend. Listen, remeasure, tweak to taste.