# Struggle replacing Old AVR - tried RZ50, 4800h, and Cinema 70 - what now?

#### Svend P

##### Active Member
Wouldn't bi-amping cause the loudspeaker to play 3 dB louder and explain the perceived difference?

OP

#### techsamurai

##### Addicted to Fun and Learning
I have a question. I know a sweep is a continuous stream of changing frequencies but my understanding is that it plays a single frequency at a time briefly.

How does an amp and speaker process sound for 50 instruments like an orchestra all at once? Do they try to divvy up the time and make the illusion of all instruments playing together relying on psychoacoustics to pull the sound together? I'm trying to understand how the amp can send 50 signals and the speaker can play 50 different frequencies simultaneously.

#### pogo

##### Major Contributor
Wouldn't bi-amping cause the loudspeaker to play 3 dB louder and explain the perceived difference?
No, this does not normally happen.

OP

#### techsamurai

##### Addicted to Fun and Learning
Wouldn't bi-amping cause the loudspeaker to play 3 dB louder and explain the perceived difference?

I don't think it doubles the power. If using an AVR, it's the same power just not shared to the binding posts with different cables.

#### pogo

##### Major Contributor
The spectral power distribution is divided, i.e. specified by the cut-off frequency. However, this does not change the volume on a conventional AVR in bi-amping.

#### BDWoody

##### Chief Cat Herder
Moderator
Forum Donor
I have a question. I know a sweep is a continuous stream of changing frequencies but my understanding is that it plays a single frequency at a time briefly.

I'm trying to understand how the amp can send 50 signals and the speaker can play 50 different frequencies simultaneously.

"All waveforms, no matter what you scribble or observe in the universe, are actually just the sum of simple sinusoids of different frequencies."

Edit: Here is a video that seems to do a good job explaining.

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#### Svend P

##### Active Member
The spectral power distribution is divided, i.e. specified by the cut-off frequency. However, this does not change the volume on a conventional AVR in bi-amping.
Yeah, it wasn't as simple as I thought. Well at least I learned something today.

A more in depth explanation from DonH56 here

OP

#### techsamurai

##### Addicted to Fun and Learning

Thanks, very enlightening - so it takes all 50 waveforms and translates them into one waveform of amplitude over time.

So if I understand this correctly (and I don't believe I am), an amp and speaker are only playing one signal at any moment which our brains are able to extrapolate into a drum, bass guitar, a guitar, a singer(s) and other instruments and even their relative position. How does that translate into frequencies? Do the amps and speakers only handle one frequency at a time, thereby essentially just playing a sweep but with different frequencies or are there many frequencies played at the same time by a single speaker?

#### HarmonicTHD

##### Major Contributor
Thanks, very enlightening - so it takes all 50 waveforms and translates them into one waveform of amplitude over time.

So if I understand this correctly (and I don't believe I am), an amp and speaker are only playing one signal at any moment which our brains are able to extrapolate into a drum, bass guitar, a guitar, a singer(s) and other instruments and even their relative position. How does that translate into frequencies? Do the amps and speakers only handle one frequency at a time, thereby essentially just playing a sweep but with different frequencies or are there many frequencies played at the same time by a single speaker?
No they don’t. It is one continuous waveform containing all frequencies identical to the one we all listen to. This is how analogue amps etc work. No dividing up.

Fourier allows to identify the individual frequencies and allows to compile every waveform with surprisingly little single frequencies.

#### BDWoody

##### Chief Cat Herder
Moderator
Forum Donor
Thanks, very enlightening - so it takes all 50 waveforms and translates them into one waveform of amplitude over time.

So if I understand this correctly (and I don't believe I am), an amp and speaker are only playing one signal at any moment which our brains are able to extrapolate into a drum, bass guitar, a guitar, a singer(s) and other instruments and even their relative position. How does that translate into frequencies? Do the amps and speakers only handle one frequency at a time, thereby essentially just playing a sweep but with different frequencies or are there many frequencies played at the same time by a single speaker?

Think of the groove on a vinyl record. It is one continuous analog wave, not 50 different waves. It all adds up. It's also like freaking magic.

To me the magic in audio is in the math. Between Fourier and Shannon (and Nyquist and others), there is some mental horsepower to be appreciated.

OP

#### techsamurai

##### Addicted to Fun and Learning
No they don’t. It is one continuous waveform containing all frequencies identical to the one we all listen to. This is how analogue amps etc work. No dividing up.

Fourier allows to identify the individual frequencies and allows to compile every waveform with surprisingly little single frequencies.

I guess my question is whether a sweep is identical to music - do the amp and speakers handle the same amount of sound when playing a sweep as when they play music or is music essentially a compilation of many frequencies playing simultaneously?

#### voodooless

##### Grand Contributor
Forum Donor
Thanks, very enlightening - so it takes all 50 waveforms and translates them into one waveform of amplitude over time.
Yes, it’s just a superposition of all waveforms. The result is a new waveform.

So if I understand this correctly (and I don't believe I am), an amp and speaker are only playing one signal at any moment which our brains are able to extrapolate into a drum, bass guitar, a guitar, a singer(s) and other instruments and even their relative position.
Yes. This is totally analog to how the real instruments would work: all the sound waves superposition into a single sound wave that reaches your ear.
How does that translate into frequencies? Do the amps and speakers only handle one frequency at a time, thereby essentially just playing a sweep but with different frequencies or are there many frequencies played at the same time by a single speaker?
They play the waveform. The waveform is comprised of many frequencies.

In fact any bandlimited signal can be constructed from a limited number of sine waves. That how Fourier works.

OP

#### techsamurai

##### Addicted to Fun and Learning
Yes, it’s just a superposition of all waveforms. The result is a new waveform.

Yes. This is totally analog to how the real instruments would work: all the sound waves superposition into a single sound wave that reaches your ear.

They play the waveform. The waveform is comprised of many frequencies.

In fact any bandlimited signal can be constructed from a limited number of sine waves. That how Fourier works.

That is absolutely amazing when you think about it. So sweeps are essentially a single frequency version of music to simplify measurements.

#### HarmonicTHD

##### Major Contributor
I guess my question is whether a sweep is identical to music - do the amp and speakers handle the same amount of sound when playing a sweep as when they play music or is music essentially a compilation of many frequencies playing simultaneously?
Test tones, like sweeps, are more demanding for amps. They test a worst case. That´s why you should be careful and not cranking up too loud or you end up frying your speakers, like some other recent poster here in the forum.

#### voodooless

##### Grand Contributor
Forum Donor
That is absolutely amazing when you think about it. So sweeps are essentially a single frequency version of music to simplify measurements.
Well, what is music? It’s really not well defined and in the eye (or rather, ear) of the beholder. The amp doesn’t know the difference between a sine wave and the latest Taylor Swift song… but come to think of it, neither can I

#### antcollinet

##### Master Contributor
Forum Donor
I have a question. I know a sweep is a continuous stream of changing frequencies but my understanding is that it plays a single frequency at a time briefly.

How does an amp and speaker process sound for 50 instruments like an orchestra all at once? Do they try to divvy up the time and make the illusion of all instruments playing together relying on psychoacoustics to pull the sound together? I'm trying to understand how the amp can send 50 signals and the speaker can play 50 different frequencies simultaneously.
All the frequencies add together to make the single time domain waveform. Here is a simple demo that shows how all the harmonics of a square wave add up to make the square wave.

Use the slider at the top to change the number of harmonics included. Look at the brown waveform...

You can also use the blue checkboxes to include or exclude the fundamental and first 4 harmonics for the green waveform.

#### Chrispy

##### Master Contributor
Forum Donor
We can beat around the bush all day, but I think it’s something with the Denon and Marantz preamp section. I tried external amps on my SR8015 and analog inputs hoping for a little different sound and didn’t get to where I wanted to be. If your not happy, some times it best to let go and just try something else. I’m not saying the Arcam is perfect but it gets me closer to what i want.
Just seems a waste of time myself.

#### peng

##### Master Contributor
Forum Donor

You are right. Utter nonsense and clearly falls into the category „flawed listening“ test and no facts whatsoever - snake oil.

@pogo you are creating a big strawmen here and you are fishing for evidence based on a flawed test. Try a different approach.
He read/watch things but only understood the superficial/buzz words. It's hopeless, if you post links for him to read and try to understand the theory behind those issues such as phase angles, epdr, damping factor, FFT, slew rate/transient distortions etc., he wouldn't bother, but just latched onto the buzz words, i.e. damping factor before, now power cube.

People even showed him the math about why his understanding of certain things he claimed was so important didn't matter that much, but there was no use, nothing could changed his mind. I now read his stuff for entertainment only.

#### peng

##### Master Contributor
Forum Donor
I have a question. I know a sweep is a continuous stream of changing frequencies but my understanding is that it plays a single frequency at a time briefly.

How does an amp and speaker process sound for 50 instruments like an orchestra all at once? Do they try to divvy up the time and make the illusion of all instruments playing together relying on psychoacoustics to pull the sound together? I'm trying to understand how the amp can send 50 signals and the speaker can play 50 different frequencies simultaneously.

The amplifier doesn't care about how many instruments are playing at the same time. It is not human so it won't know the difference anyway. It just amplify whatever goes in and output the same information but of higher magnitude. If distortions is 0% (of course it never is), then the output signal will replicate the input signal waveform, and there would be no sound signature that people like yourself often claim there is for every amplifier. If distortions is >0, then whether it could be discerned by humans would depend on how high it is above 0, and of course there are other factors too. Back to your question, no matter what the input signal to the amplifier look visually, the amplifier only sees one value at one time, so again, it makes no difference to it whether it is a pure sine wave or an ugly wave that is composed of hundreds of sine wave combined together (as mentioned by antcollinet's post#436). It will just amplify the input signal's magnitude moment by moment. Elliot Sound has an article on that, I can post link if I can find it for you.

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#### mimoza

##### Member
Pure direct has no processing applied other than a crossover for sub / mains integration, so cannot be capped at 1100Hz by definition. Audyssey correction is capped at 1100Hz. The point was to show the improvement XT32 makes over pure direct. And then to show how XT32 hammers the upper frequencies in sometimes not so nice ways.

Let me help you out. It is indeed quite flat and accurate. Left and right together with psychoacoustic smoothing against target curve. Within ~2dB of target everywhere:

View attachment 320858

This is a very good result that sounds excellent. It doesn't get much better than this.

Anyway, you did not bother to respond to any of the substance I posted, and reading over your comments here and in the 4800 review thread makes be believe this is a lost cause. I hope you figure it out.
Sorry off topic but your curve is so nice, what does your room looks like?

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