Connecting a subwoofer and integrated amp

[@juanbaclavab]

Many don't know the Velodyne SMS-1 Subwoofer Management System. It's a device that you connect to any amplifier through RCA, XLR or speaker level. It then processes the signal to up to 3 subwoofers at the same time. It's loaded with features amd connections. Has video output, full 8 band parametric eq, subsonic filters, crossover slopes up to 48 db/octave, automatic room correction with included professional microphone, etc. It improves the performance and frequency response of any subwoofer and it's the only decice that converts speaker level connections to LFE/RCA so you can make use of any stereo amplifier.

[@DarkJeffau]

This looks like what I need.

[@gdownz1044]

I'm sold on using the speaker inputs on my sub that Paul always preaches to do and he's absolutely right about it. Although ALL of the new REL subs I've looked at on their website are either RCA LR or LFE.. 🤔 I thought they had speaker inputs and was surprised to see that.

[@razisn]

They offer high level inputs AND line level inputs AND LFE.

[@Roof_Pizza]

@@razisn I see 3 of the HT series without them.

[@lexicon612]

They have their own system for high level inputs. It is different than the usual banana inputs or binding posts so not obvious at first glance. I don't believe they ever made a sub without high level inputs. I could be wrong though. Look again.

[@razisn]

@@Roof_Pizza this is about their music series subs… In any case 3 out of the many is far from 'ALL'..

[@razisn]

@@lexicon612 It is not a proprietary connector system. They are SPEAKON connectors, well used in the pro audio industry.

[@jeremythered74]

Thank You Very Much Mr. McGowan!!! 👍👍

[@larryhoffman7471]

Just turn the filter on the sub to a higher frequency than the filter in the integrated.

[@bigmacfullerton7870]

I thought it needed to be lower

[@bradtowne2305]

I have two 5.2 channel rooms in my house, and the wall mounted plates for connecting all the built in speakers includes only a single RCA line level connection. So I have to use the Line Level signal. I guess what is the issue since my sub also has a filter?

[@joansev3257]

Is LFE to av amps only , or can a sw output of a stereo integrared amp be also connected to the sw LFE ?

[@logtothebase2]

I think this is about the most confusing question in HiFi, as Sub needs a low pass filter an amplifier and a connection to the preamp, ether left right or preferably both channels combined. Which particular box those things might be in and how you connect them together is far from trivial, the industry should adopt clearer nomenclature and specification so toy can plug in the right way and adjust the volume and cut off to your own requirements..

[@GeneA.69]

😂… I was with ya up to the end and then you lost me. Now I have to watch and VERY carefully l listen to this video for the 4th time 🙄

[@lexicon612]

The only acceptable use for RCA inputs for subwoofers (imho) is in complex home theater environment's. Paul touched on this scenario. Subwoofer's need the same sound signature that is being fed to your main speaker's. The only way to ensure this happens is by exclusively using the high level inputs on the subwoofer. If you use the RCA inputs the main amplifier cannot add its sound signature to the bottom octaves of any soundscape created by your system. The preamp (section) adds its signature instead. Not what you want if sound quality is the goal. Exact same cabling you use for your main speaker's is what should be used to wire your stereo sub's. Yes done right you run stereo sub's exclusively. Well multiples of 2 as the new REL 6 packs are Incredible!

[@bobbg9041]

Your receiver's low pass out put might be a 24db per octave crossover wile the filter on the sub is only 12db per octave. The 24db per octave is a fast slope cutoff this matters if your main speakers have good low-end output it keeps you from having a bump in the audio output at the selected frequency its crossed over at. Also a one rca connection could be a ditigtal signal if thats what the receiver passes and the dc converts in the sub if any one of them have that capability. A da converter in the sub would help cut down noise on the lines. But might not be as good as the da converter in the receiver. This comes back to the question, do wires matter? And the answer is yes. But can you hear the difference? In my personal oppion all signals should be via optical cables, wile tosslink is antiquated its still the best option. Light doesn't distort if its a strong signal. It does have it limits in length. Someone made a comment using a sum of right and left channels But bass is over the left channel Thats how its recorded if you run a left and right subwoofer then time aliment would cause a drop in bass output. A one wire connection is the sum of both channels in the receiver you get all the benefits of harmonics from it just the same as using L and R signals. As for running both the crossover on the reciver, then on the subwoofer it doesn't matter its not going to change the sound i disagree with you Paul. Here is my reason: let's say your receiver has a high-pass subsonic filter then your full range speaker has both a midbass and tweeter The tweeter has a crossover on it in the form of a capacitor thats 2 crossovers in the signal path. Its not going to change the sound output with both of them past its crossover point. The last crossover point will be the end result or the highest number . Take your typical 3 way speaker and a good avr your avr has built in filters so you can set it to cut out low-end bass your speakers can't play effectively lets say it passes everything above 45hz now your 3 way speaker has a built in crossover with a midbass midrange and tweeter each speaker is crossed over at its point above the start point of 45hz if you remove the 45hz the midbass falls flat on its ass trying to make bass because the speaker only has 2 points of crossover one above the midbass, and one above the midrange nothing to stop the low-end bass the speaker can't play. Most people do not know how to set up the crossover point on the sub many of them can crossover at 120hz it should not be above 60hz its gets sloppy you get tighter cleaner bass at 60hz and down to 35hz. And yes i like a 24db per octave crossover over say a 12 db per octave.

[@johnnytoobad7785]

I've been doing this for years with NON-LFE high impedance sub-amp inputs. (plate amp inputs) Just set the x-over on the sub-amp to higher freq (say 180hz, typically 3-4 o'clock on the knob) and set the external active crossover freq to a lower (120 hz) value. Basically your creating a "staggered" 4th order LPF at 180hz and above (in this example). So you just get a "steeper" roll-off at 180 hz and above. In my case this arrangement actually improved the sound of the sub. Most built-in plate-amp LPF's are not that great anyway.

[@carlosalvarez7445]

Ughhh... THAT is confusing! I have the Sprout 100 which has a sub out, and I want to control the crossover in my REL sub, but you are saying that is not a good thing to do? I would expect it should be something users could have a choice about... wouldn't it?

[@clothyardshafts]

Except that some subs (RELs) require you to connect to amps in a very specific way namely the amps speaker terminals.

[@razisn]

Absolutely no REL requires you to do that.

[@gtric1466]

By using the full range sub out on my integrated i use the high pass @ 60hz on my sub. reason being i can adjust the gain of the sub through my integrated, great for different sources. Even if i had a remote for the sub, why have to fiddle with 2 remotes.

[@Oystein87]

In a stereo system..: RCA cables via L/R pre-out Done

[@thomasalexand]

Using one or two rca cables into the sub?

[@Oystein87]

@thomasalexand In my case I use a mono out but with a Y-cable so I use both inputs on the sub. But with normal L/R pre-outs O would use both to get the signal from both channels..

[@mikeshuck2760]

What was not detailed. Line out or Amped out to Passive or Powered sub? Raises a whole other discussion.

[@thomasalexand]

Agree. My Rotel A11 Tribute amplifier doesn't have a subout. It has a preamp out - a set of two rca. Do I connect one or two rca cables to the active sub?

[@theaustralianconundrum]

It's very simple.

[@hoobsgroove]

I don't think there's any issues doubling down as you put it, why should they be? You're looking for low frequencies anyway ideally in majority of circumstances below 50 Hertz. can't see it's an issue should help actually to get even lower down. I think majority around 80 hurts output sub out.

[@randomsomeone1617]

It adds filters on filters if I'm not correct. You don't ever want to do this unless completely nesacaary

[@randomsomeone1617]

Very possible I'm wrong

[@hoobsgroove]

@@randomsomeone1617 yes that's what he said filter on filter I don't think that's an issue can't see why. he didn't explain why that's an issue

[@cuoresportivo155]

@@hoobsgroove because the slope is now random: for example 12dB/octave from the integrated, and then you add another 6-24dB from the sub LPF, which begins at a random poin. This doesn't correspond with the HPF going to the main speakers.

[@Jorge-Fernandez-Lopez]

Speakers away from the wall might have partial cancellation between 70 and 100 Hz (depends on the distance). Sometimes two subs with a higher crossover frequency can be a good idea, whereas only one sub can be harder to set up without a very low crossover.

[@bigmacfullerton7870]

More confused than ever 😢

[@bigmacfullerton7870]

If I have the Yamaha A-S801 with a sub out with a cutoff at 100Hz can’t I just run a regular analog red and white chord from the amp sub out to the subwoofer in and run the sub at about 60Hz so it wouldn’t interfere with the amps 100Hz cutoff? If I’m even making any sense. Not sure 🤔

[@RoderikvanReekum]

Do not listen to this! Connect your subwoofer trough the low level RCA output! This is misinformation!

[@hometheaterfever5]

Exactly. He made a simple connection so complex and called a complicated connection simply. It’s the opposite of what he said

[@DIEME1970]

So I have a REL1003 sub connected via a single sub cable to a Marantz pm6007 sub output, am I right or should I split the sub cable at the sub and go left/right input?????? So confused.

[@hometheaterfever5]

@@DIEME1970 No, don’t change anything because you have it connected the correct way. Ignore the video because it’s False information to confuse the heck out of you. Not only is it false, but it’s an ancient way to connect in video. The only time you split cables and connect left and right is when one has an OLD receiver which doesn’t have LFE subwoofer connection. But if your subwoofer has LFE connection, and your Integrated Amp, AVP or AVR has subwoofer connection, just use the one cable to connect.

[@DIEME1970]

@@hometheaterfever5thanks bro, appreciate the help👊🏼

[@hometheaterfever5]

@@DIEME1970 anytime brother 🤠