@larryincmh yes a guitar solo. I was incorrect when I said it was around 50-60Hz. It's actually below 50Hz. And as you stated, you could simply hear it on the right channel. I'll attach a picture of the visualizer on my streamer to show it when I get to a computer. Therefore, if you have an 80Hz crossover using LFE, it will come from both channels instead of just the right. It will be less stimulating and dynamic.
LFE vs High-level subwoofer connection, for FIDELITY
Simple as it sounds. What subwoofer connection method offers higher fidelity, and why? The LFE, 75 ohm unbalanced RCA cable. Or high-level, speaker wire to the binding posts of the amp. I am running 2 KEF KC92 subwoofers to a Soul Note A-2 Ver. 1 amplifier.
Grok Ai states it matches your speakers tonal balance, timing cues, and sonic signature, because it shares the same signal path through the amplifier that your speakers sound travels through. It’s also a great way to get tube or amp sound into your bass region. My LFE outputs from my Khozmo Acoustics pre-amp, bypassing the amplifiers elite and favorable sound. The PS audio subwoofer had not been released yet or I’d have swoope those up, instead of the KEFs.
Also, has anyone heard that it is straining or damaging to a truly balanced, direct coupled amplifier to use high level inputs? This was mentioned to me and I can’t recall how reliable a source it came from.
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@larryincmh here's a visualizer screenshot from my streamer. You see there's signal in the right channel but there are no vertical bars above 50Hz. That means the signal is below 50Hz.
This is what a more full signal looks like https://mega.nz/file/OcpiBRRZ#KCpKJ74dFsX-ZwSlyTb7bxrltwYbFxvCfE1IVPR9V_I
I also have a desktop software that shows more detail when I get to the PC. |
There has been some very good technical explanations thus far. Just adding a couple of extra points of clarification. LFE = Low Frequency Effects and is strictly an AV/Surround Sound term. It’s the .1 or .2 part of a 5.1 or 7.2 system reserved for sound effects like explosions. The subs are sent 100% of the LFE content + whatever content is sent from the main and surround speakers as per their crossover settings, unless they are set to large. The sub is simply configured to bypass it’s internal crossover if the AVR is managing the signal sent to the subs. In a HiFi stereo set up, there are many examples of music where lower frequencies are coming mostly, or exclusively from one channel or the other, or separate sources of low frequencies coming from left and right (E.G., Friday Night in San Francisco.). So with stereo subs, while it is ideal that you can’t "hear" the localized subs , each sub should seamlessly augment the L or R main. Yes there will be some mono-blending. The other advantage of treating subs as stereo pairs, is adjusting for the room (assuming you have good EQ capabilities built in or use external DSP). As an example, many of us have rooms that are not acoustically symmetrical, even with treatment. So using REW measurements, the EQ settings of my subs are each set differently. Subs also pressurize the room. In my case they are behind the MLP, closer than the mains, to pressurize the open space behind the MLP and to tame bass build up in the corners of the front wall. (Pics in my virtual system). I cannot tell that I have subs behind me. My baby MBLs just sound really big. Point is, properly located and configured stereo subs do more than just augment omnidirectional bass. If you have incremental phase adjustment, rather than just 0 or 180 like REL, you can potentially bypass the sub crawl mentioned earlier by reversing the polarity on your speaker taps and playing a tone at the crossover frequency to L/R speakers separately. Adjust phase for each sub until the tone is the quietest. They are now in phase. Don’t forget to put the speaker cables back to the correct polarity. Lastly, if you choose a straight-up high-level / speaker-level connection, you can connect from the speaker tap(s), which may be more convenient that connecting to the amp, or use less wire. |
@larryincmh here's the spectrum from a desktop software. It's more accurate and is able to pick up more detail. The left channel is orange. You can see a fair bit of content below 80Hz on the right channel. Again, that was ~50Hz bass you could localize with your ears. https://mega.nz/file/nUpgDRSR#zUWAdeA4LpDZaXdVsJ8HGblhy9q-z6UZ7Knz0SOJt8M |
@macg19 thank you for the tips and pointers. As for my setup, I only use a single pattern for my system. It is set at 7.2.2. I have all my speakers set to small, and there is a setup that says to always use the subs and that the sub layout is "mono x 2". I do recall seeing something that said that when set this way and while it uses the LFE outs for the bass, it is really not processing or dealing with it as it would a movie LFE. At any rate, I have been happy with the setup and as stated I am probably 90% music listening anyway on my system. I use "straight" for most everything, including the turntable, WiiM Pro input or reel player. @bartsw thank you also for these sprectrum analysis. I will have to figure out some software to allow to me track this on my system, since I do have a computer in the room where the system lives. I spent a bit of time after we chatted playing some of my more bass heavy favorites and again came away quite happy with the sound. I will do more testing tomorrow. |
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