High level vs low level subwoofer inputs

Is it possible the high level inputs of a subwoofer actually consume some of the main power amp's power?

[TT-eois]

After removing the preamp from my system (used the line level RCA LP Sub output for the past 12 years), went with the main amp's speaker outputs to include the Sub in the new configuration (sub has high level inputs). As Paul advocates, found my stand monitors playing full range Integrates Beautifully and Seamlessly with the sub (w/sub amp internal LP crossover set @60hz)! AMAZING tonality/timbre blend and total system balance with soundstage/imaging integration that says, "LIVE, I Am THERE"! 😀

[coreymalis]

This is great! I'm still using the Polk Audio PSW650 (dual 10) for 22 years and even in the manual it recommends using the High Level (speaker wire). This is probably why I can also get away using Pure Direct on the receiver as the entire signal gets to the sub and is broken up in the sub as well. I'm expecting the sub not to live too much longer and will replace with another High Level option when needed. Thank you

[JBernhard]

One little thing left out... on my Dayton Audio 12" sub woofer, the high level in and out were common for each of the negative posts, and the positive posts each have a 220uF bi-polar 50V capacitor. These caps act as a high pass filter, for a 8 ohm speaker, filtering at ~90Hz. Therefore the out speakers do not deal with signals below 90 Hz.

[KG-siyb]

I tried today with Wharfdale EVO 4.2 and 2 SVS SB 1000pro and wow, big difference! Thanks for your Videos!

[billd]

To me, the biggest issue with most subs is latency. The DSP circuitry is slow enough. Add the typical mass of the majority of sub drivers and trying to get it them moving and you now have phase issues. You really need a proper high pass filter or at least a very good crossover setting to mitigate them.

[steverosales]

I agree, with my front stereo speakers in my mini home theatre, I prefer the sound of the high level input on my dual SVS SB 1000 vs the RCA ❤

[bruss]

I use the high level with a 8 wpc SET tube amp. The added AB amp in my sub boosts the signal nicely to drive it. Tough to get bass on 8 watts.

[Vincent-gelr]

Hi Paul !,
I love your videos, I follow your channel from France (Montpellier) as an 52yo audiophile with electrotechnics engineering backgroung not sound engineering...
Your videos educate us in this hobby we all love here !
B U T it’s sometimes a bit confusing. Would it be possible to have a little drawing or photo to help us to follow your explanations especially when it comes to connexions between elements.
I admire the energy you show in the transmission of your knowledges and your passion for sound and electronic design.
Best regards.

[devaplan]

Your advice to use the speaker connections on the sub is noted, but some power amps like my Bel Canto Ref 1000s don't like it and I have to use the pre amp outputs to feed the sub.

[richardt]

It's David Suchet, and yes, he is an incredible actor. Check out the BBC's The Way We Live Now if you want to see a towering performance.

[hoobsgroove]

speaker connection high voltage connection cuts it down to 2V-3Vs same as line input and it's better because it adds delay to the sub, always use thin gauge wire 22 gauge or less

[bencausey]

My KEF Kube 12b’s are wonderful using the speaker level inputs. 😀

[MonsAaZeiger]

Hey,
So I'm also just getting into subwoofers and although I've seen most of your videos on how to connect them (I think), I still dont understand how it works.

I currently have a NAD c162 preamp, NAD c272 power amp, a pair of Klipsch rp160 and an older SVS pb12-plus (I think the woofer might be overkill for my system, but I found all of this in various lofts and storages and nothing beats free)

On the back of my power amp there are two sets of speaker outputs. Am I getting this right if I connect my subwoofers high level innput to the second pair of speaker outputs on the power amp, or should I connect the woofer to the first set of speaker outputs on the power amp and then connect the Klipsch speakers to the subwoofers high level output?

If the latter is correct, how can I be sure that I'm not giving my Klipsch speakers to much power and end up blowing them?

Thanks for your videos thus far anyways! They have helped me understand many things.

Best of regards,
Mons

[nafnaf]

Yeah something like a REL subwoofer (or sub-bass system as they like to call it) when connected over the high level connection, has in input impedance around 150, 000 ohms. Compared to speakers that is essentially no load at all, even though it is using the higher voltage powered connection from the front right and front left.

[helderdemouramartins]

what is the reason for some subwoofers (that provide high-level inputs) not to have/provide high-level outputs? Less production cost? Don't we lose part of the subwoofer crossover "work" when paired with some floor stands?

[ToadStool]

But Paul, with high-level inputs can we also be assured that the sub's amp will not induce its own sonic signature into the sub's output? If not, then what's the use of retaining the main amp's signature if the sub amp is also inducing its own sonic signature? In such a case, is not the sub's resulting output some sort of hybrid of the main amp's and the sub amp's sonic signatures i.e. a box of chocolates?

Also, as in the case of REL subs, can we be assured that REL's high-level input cables won't induce their own sonic signature much like a speaker cable or an interconnect? I don't recall reading any reviews on REL cables - can we also be assured that the REL high-level input cables' performance is above reproach i.e. are equal or superior to the speaker cables in use?

So at this point and at the very least we potentially have the main amp's sonic signature + the sub amp's sonic signature + in this case REL's high-level inut cable's sonic signature + the main's speaker cables sonic signature. Come to think of it, how might the impact of adding unnecessary sonic signatures to the mix be much different that say, insisting on the sonic signature of an active pre-amp over a passive pre?

Besides the above, aren/t these pretty much the opposite of a more simplified strategy? Simplified by eliminating as many unnecessary sonic signatures as possible? Actually, such a strategy can be rather impressive sonically when eliminating excess sonic signatures and across all frquencies - not just the bass regions.

If true, doesn't any of this defeat or compromise the preservation of the main amp's sonic signature concept? Or is trying to retain the main amp's sonic signature at all costs truly worth the probable sonic compromises elsewhere?

Seems to me the logic behind high-level connections is little more than a hypothetical dream (but only when taken on its face) that could never achieve its intended purpose i.e. retain the fidelity of the main amp's sonic signature without inducing other sonic signatures into the mix. And this certainly is not to say the REL's can't deliver superior or extremely musical bass. From what little I think I know and heard of REL subs, the potential for a superior bass seems pretty high. Even so is it not possible that REL's success might be in spite of its high-level inputs rather than because of?

Sorry but the high-leve inputs argument seems just a bit difficult a concept for me to fathom every time I read about it watch a video about it. REL seems to have quite a reputation and quite a following. Even so, the logic just seems odd to me.

[samlee]

If I have 2 pairs of speakers wired up in parallel to a budget NAD amplifier, would adding a couple of high level input subwoofers in series or parallel put any strange load on the amplifier ???

..I think Paul just answered my question but I'm nervous about having potentially 16 speaker wires going into a stereo amp... 😅? !?

[timschutte]

Hey Paul. You didn't talk about the frequency aspect on using the high level input. And what that does and it's adjustability.
It's let's you cut OFF your selected low frequency to whatever speakers you have them hooked up to.
In other words.
It let's you use a much smaller bookshelf or satilight type speaker of higher quality since they are smaller a person can afford a higher quality without any bass loss since your using the subwoofer.
I have a small system in my bedroom .
Using a 10 inch Dayton sub.
I am using Jamo c932s
It sounds fantastic.

[jiml]

That goes against everything I have learned and heard in the past I have been using RCA instead of speaker outs forever. I have some newer subs that have a XLR inputs will have to try these.

[XSFlanger]

I wonder if it's worth having all the cabling mess and four Y splitters (two for each side) for that "character" of my Denon, rather than having one RCA cable going right into Sub's integrated amp...