How to optimize Subwoofer integration?

0 Members and 2 Guests are viewing this topic. Read 461 times.

who?me?

How to optimize Subwoofer integration?
« on: 7 Nov 2017, 12:17 am »
I’m at the point of wanting to integrate a proper sub into my 2 channel system.

Hey folks,
I understand that I can control the gain and frequency of the low end of the sub,via the sub.

But is there a way to do the inverse? Can I reduce the low end of the speakers to about 45 hz and use
the sub instead from about  44 hz and below?

If possible, how would that work? e.g., use an external crossover for the floor standers?
The problem is that there is too much output at around 30-50 Hz if I use both the speakers and the sub.

thanks!! Gary

Rig: (Bel Canto DAC–> PrimaLuna Dialogue HP tubed integrated–>
Dali Helicon 400 floor standers, Spatial M3 Triode Masters, and coming soon Dynaudio S3.4 Contours (thanks Joe)
« Last Edit: 7 Nov 2017, 03:54 am by who?me? »

John Casler

Re: How to optimize Subwoofer integration?
« Reply #1 on: 7 Nov 2017, 02:08 am »
Step One:  Find the natural "roll off" of your mains and "roll in" your sub at that frequency with as little overlap frequency as possible
Step Two:  Place your sub so it is EXACTLY the same distance from your listening position as your mains

Yes, you can find and use a XO with High Pass and Low Pass Outputs if you want to adjust the Mains bass.

Early B.

Re: How to optimize Subwoofer integration?
« Reply #2 on: 7 Nov 2017, 03:07 am »
Yes, you can find and use a XO with High Pass and Low Pass Outputs if you want to adjust the Mains bass.

Yeah, you can do that, but you're potentially creating other problems. High pass filters (F-Mods, for example) are generally cheaply made and adversely affect the sound. Many of us have successfully integrated subs while running our mains at full range. More important integration issues include room size, musical tastes, subwoofer placement, sub crossover settings, number of subs, and quality of the sub(s).   

who?me?

Re: How to optimize Subwoofer integration?
« Reply #3 on: 7 Nov 2017, 04:12 am »
thanks for the help. I am confused by all the options these days:
1 mono LFE vs Hi Level Inputs vs Low Level Inputs vs Summing L/R channels, etc

I am interested in this sub: the Zu Audio Undertone subwoofer http://www.zuaudio.com/subs/undertone.
It does say there is a Signal Processing Bypass, but I dont know how it works.

here is a pic of the backside, and connections options:
From Zu's website:

 "Line-Level Input: yes, RCA (left and right summing)
Sub Line-Level Input: yes, RCA
Speaker-Level Input: yes, 5-way binding posts (L/R summing)
Tunability: yes, very
Signal Processing Bypass: yes, switched for those that want to integrate more elaborate signal processing but desire to take advantage of the excellent amplification of Undertone."

Also: from Zu website, "It is a down-firing subwoofer with active signal processing and built in amplification. It accepts line-level feeds (RCA left and right summing), sub feed (RCA) and speaker-level (five-way binding posts, left and right transformer isolated and summing)."

I couldn't find a better image online that this one:
« Last Edit: 7 Nov 2017, 06:09 pm by who?me? »

mcgsxr

Re: How to optimize Subwoofer integration?
« Reply #4 on: 7 Nov 2017, 12:03 pm »
A minidsp could also be used to achieve what you’re after.

I have done it with pro analog crossovers too.

artur9

  • Jr. Member
  • Posts: 60
Re: How to optimize Subwoofer integration?
« Reply #5 on: 7 Nov 2017, 12:29 pm »
I've spent a lot of time integrating subs (too much!).  There are lots of different ways to do it depending on what you're trying to achieve.

I have found that hi-passing my bookshelf speakers does give them an additional level of clarity so I have done it that way.  But that does make things a bit more challenging.

One thing I can recommend is to use Room EQ Wizard to measure your speakers in-room response.  Once you get the hang of REW the placement and integration of the sub becomes much more scientific, if not quite 100% repeatable.

who?me?

Re: How to optimize Subwoofer integration?
« Reply #6 on: 7 Nov 2017, 06:24 pm »
Step One:  Find the natural "roll off" of your mains and "roll in" your sub at that frequency with as little overlap frequency as possible
Step Two:  Place your sub so it is EXACTLY the same distance from your listening position as your mains

Yes, you can find and use a XO with High Pass and Low Pass Outputs if you want to adjust the Mains bass.

thx John, looks I need to do some research on external XOs. And after seeing everyone put their sub in the corner of the room my entire adult life, it makes perfect sense to place it same distance from speakers for timing.

who?me?

Re: How to optimize Subwoofer integration?
« Reply #7 on: 7 Nov 2017, 06:25 pm »
A minidsp could also be used to achieve what you’re after.

I have done it with pro analog crossovers too.

will check it out. I've heard mixed reviews of DSP engines. Any suggestions in particular brands? types?
thx

who?me?

Re: How to optimize Subwoofer integration?
« Reply #8 on: 7 Nov 2017, 06:26 pm »
I've spent a lot of time integrating subs (too much!).  There are lots of different ways to do it depending on what you're trying to achieve.

I have found that hi-passing my bookshelf speakers does give them an additional level of clarity so I have done it that way.  But that does make things a bit more challenging.

One thing I can recommend is to use Room EQ Wizard to measure your speakers in-room response.  Once you get the hang of REW the placement and integration of the sub becomes much more scientific, if not quite 100% repeatable.

Thx. I'm assuming Room EQ Wizard is a type of DSP product?
Will investigate.

mcgsxr

Re: How to optimize Subwoofer integration?
« Reply #9 on: 7 Nov 2017, 07:00 pm »
https://www.minidsp.com/ - I would start here and read about their solutions.  Available in US and Canada, and highly regarded as simple devices that can do many different things.

I am presently still using a pro Xover in the analog domain, as that was the fast, cheap and locally available choice when looking earlier this year.

But I know that the minidsp offers a better solution for me long term.

John Casler

Re: How to optimize Subwoofer integration?
« Reply #10 on: 7 Nov 2017, 07:18 pm »
thx John, looks I need to do some research on external XOs. And after seeing everyone put their sub in the corner of the room my entire adult life, it makes perfect sense to place it same distance from speakers for timing.

The "corner loading" is often employed to take advantage of room boundary gains.

However, it causes Phase Coherence Issues when the focus is on two channel music.

Equidistant and time alignment of the subwoofer will reduce these phase issues BUT. . .the will be at the sacrifice of POWER.

artur9

  • Jr. Member
  • Posts: 60
Re: How to optimize Subwoofer integration?
« Reply #11 on: 8 Nov 2017, 01:33 am »
Thx. I'm assuming Room EQ Wizard is a type of DSP product?

It's measurement software that runs on Windows or Mac.  The software is free but you'll need a calibrated mic to use it and those run around a hundred dollars.

There are other measurement "solutions" out there as well but I've been satisfied with it.  This link REW is an overview put together by Gik Acoustics.

artur9

  • Jr. Member
  • Posts: 60
Re: How to optimize Subwoofer integration?
« Reply #12 on: 8 Nov 2017, 01:36 am »
...the will be at the sacrifice of POWER.

In your opinion, what's the best way to mitigate this?  More subs (stacked)?  Bigger subs?

JackD

  • Full Member
  • Posts: 773
Re: How to optimize Subwoofer integration?
« Reply #13 on: 9 Nov 2017, 01:44 am »
who?me?

There are multiple free apps on either app store that you can use initially with your phone to get some idea where in the bass region your problem really is. Of course they are not as good as REW with a dedicated microphone but they will get you in the ballpark.  In most rectangular shaped rooms it will fall in the 40-80 hz range but may actually be higher than your guesstimate.  If you room is untreated and they are acceptable then much of your problem can be mitigated with corner bass traps before buying more gear.  Adding only one sub to the room is not likely to help your situation where two might.

John Casler

Re: How to optimize Subwoofer integration?
« Reply #14 on: 9 Nov 2017, 04:36 pm »
In your opinion, what's the best way to mitigate this?  More subs (stacked)?  Bigger subs?

Yes, multiple subs in different positions (but still the exact distance as your mains) can help.

As well, with multiple subs the room interactions are "smoothed" due to the bass not interacting with the exact same room boundaries.

As a DEALER I have many subs, and they all fit some scenarios better than others.

One even has SmartPhone/Pad control with an onboard equalization.  If you are limited to a single sub, and don't care to invest in more sophisticated and costly programs and mikes, it is helpful.

who?me?

Re: How to optimize Subwoofer integration?
« Reply #15 on: Yesterday at 05:23 pm »
Thx Arthur. Gearing up to read about REW, I noticed there is an article that says you can integrate REW with minidsp device. Any recommendations for a room EQ mic?

It's measurement software that runs on Windows or Mac.  The software is free but you'll need a calibrated mic to use it and those run around a hundred dollars.

There are other measurement "solutions" out there as well but I've been satisfied with it.  This link REW is an overview put together by Gik Acoustics.

who?me?

Re: How to optimize Subwoofer integration?
« Reply #16 on: Yesterday at 05:31 pm »
john,
good point about loss of power with only one sub at equal distance to speakers.
however, the sub I am interested in, the Zu Undertone, is a beast and goes down to 14hz, and tight at low volumes.

Honestly, even integrating a ONE sub in my listening room is kind of pushing it in terms of space and energy build up. So instead of opting for 2 subs that will offer balance but will be less quality than the Zu, I am choosing one solid sub to place in the middle b.w my floorstanders.

The Zu sub "does it for me", and probably would do it for you too if you heard it, or its big bro the Submission. B/c you will SUBMIT to its bass. deep and powerful.

I WILL need to employ some acoustic treatments, and I've used Roomtunes in the past, so i have a supply of them to try out once I get the sub and placed in room .

The "corner loading" is often employed to take advantage of room boundary gains.

However, it causes Phase Coherence Issues when the focus is on two channel music.

Equidistant and time alignment of the subwoofer will reduce these phase issues BUT. . .the will be at the sacrifice of POWER.

John Casler

Re: How to optimize Subwoofer integration?
« Reply #17 on: Yesterday at 05:42 pm »
john,
good point about loss of power with only one sub at equal distance to speakers.
however, the sub I am interested in, the Zu Undertone, is a beast and goes down to 14hz, and tight at low volumes.

Honestly, even integrating a ONE sub in my listening room is kind of pushing it in terms of space and energy build up. So instead of opting for 2 subs that will offer balance but will be less quality than the Zu, I am choosing one solid sub to place in the middle b.w my floorstanders.

The Zu sub "does it for me", and probably would do it for you too if you heard it, or its big bro the Submission. B/c you will SUBMIT to its bass. deep and powerful.

I WILL need to employ some acoustic treatments, and I've used Roomtunes in the past, so i have a supply of them to try out once I get the sub and placed in room .

You are correct that the ZU seems to be a great sub, but Power and Depth will not overcome Physics.  In fact, they are affected exactly the same as Less Powerful performers, but because their performance is greater, the challenges are too.

Subs have their own special place in the Audio World. and it is always filled with trade offs.  It is rather easy to tame mid and high room reflections via treatments and equalization.

However the size and power of BASS frequencies present significant challenges, and the BIGGEST Challenge is getting well developed bass at your listening position (usually in the center of the room)

But, setting up and placing a sub, or subs is part of the challenge, and hopefully reward.

who?me?

Re: How to optimize Subwoofer integration?
« Reply #18 on: Yesterday at 05:49 pm »
Thx Jack. I recently downloaded an App called AudioTools. A friend from the audio club recommended it.
It is actually pretty sophisticated and offers more advanced analysis. It is modular, so you buy the initial App, then can pay more for apps with the App.

It was expensive as far as Apps go, $20, but I've only paid for 2-3 apps my whole life. I just needed something to get me going. And this is my passion, so $20 well spent.

My room is about 12 feet by 19 feet, and is "L" shaped. So that the side that is 12 feet actually extends to 25 feet into my bedroom from my listening room. Attached is a crappy home made drawing.
Note: the image is stuck sideways, so you have to turn your head to the right!! sorry




who?me?

There are multiple free apps on either app store that you can use initially with your phone to get some idea where in the bass region your problem really is. Of course they are not as good as REW with a dedicated microphone but they will get you in the ballpark.  In most rectangular shaped rooms it will fall in the 40-80 hz range but may actually be higher than your guesstimate.  If you room is untreated and they are acceptable then much of your problem can be mitigated with corner bass traps before buying more gear.  Adding only one sub to the room is not likely to help your situation where two might.