Has to do as much as chips radiating from their top 😀. Or are you saying chips are radiating in the KHz to MHz range frequencies?
Yep, known since ages, if someone says "causes less problems" it raises the FUD level to former unknown regions......
Another interesting quote from Bruno from here relevant to all recent discussions on this thread
So one major factor for the reported great sound of this amp module is, according to Bruno (the main designer, I believe), due to the very low IMD compared to other amplifiers. The problem with two tone IMD measurements has always been that the IMD products tend to be far below what is considered the audible threshold so how to reconcile this? If indeed, IMD is the underlying factor, how do we show either that these low amplitude distortions seen in two tone IMD plots are audible (new psychoacoustics testing?) or alternatively show IMD in another way that demonstrates the connection to audibility more directly?
IMO, this is the approach that is pushing the envelope in audio & discovering what's possible - an open-minded approach to audio design - refreshing
So one major factor for the reported great sound of this amp module is, according to Bruno (the main designer, I believe), due to the very low IMD compared to other amplifiers. The problem with two tone IMD measurements has always been that the IMD products tend to be far below what is considered the audible threshold so how to reconcile this? If indeed, IMD is the underlying factor, how do we show either that these low amplitude distortions seen in two tone IMD plots are audible (new psychoacoustics testing?) or alternatively show IMD in another way that demonstrates the connection to audibility more directly?
IMO, this is the approach that is pushing the envelope in audio & discovering what's possible - an open-minded approach to audio design - refreshing
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How do you know a smaller IC is less problematic? I have a 3 mm^2 ARM Cortex M4 with Bluetooth low energy radio in the same package on my desk. PMIC same thing, almost as small but 5 switching regulators. Those are all chip scale packages.
FUD, you know, a theory with no evidence proposed by someone who doesn’t seem to know what they are talking about in order to plant seeds of doubt in support of undefined problems.
Well, structurally, no, but, a chimp on a laptop could type a Shakespeare sonnet by change alone..
Richard claimed that when his DAC came back from RFI treatment, he found it to sound better than before he shipped it out. The DAC3 has freakishly low artifacts as in no coloration or anything audible at all that shouldn't be there. Bog standard. Unless the upgrade company really screwed up something, how can a guy with 70+ year old ears, from memory alone, hear a difference, between something that is perfect and something that is even more perfect? With no doubt weeks in between. With a MiniDSP in the middle of the signal chain (midfy at best, a generic DSP with built in DAC's).
BTW, if I remember correctly, Mark, you found your own DAC3 to sound better than Richards, while yours is untreated.
This opens the possibility that indeed the upgrade company mucked up Richards DAC3 for good. Otherwise, there is no logical explanation that anyone should have heard a difference.
1. Where did you get that from?
2. What justification for it being midfi have you got?
My post wasn't quoted but still visible to you for some reason. 🙄
To find that out, one should rely on bias uncontrolled subjective evaluation?
Like i just said... good practices.
-RNM
🙂 😎
Someone was paying attention as to what was said......
And, I agree with you about the miniDSP.
THx-RNMarsh
Good question - do you reckon they are of the same nature & therefore higher IMD in speakers will mask any IMD created in the electronics?
But to my thinking IMD isn't just a figure - it's various additional tones/frequencies created by the reproduction which weren't in the original sound. It's very probable that IMD from electronics map to some different frequencies than IMD from speaker drivers & as a result are audibly perceived.
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isnt the HF picked up one way or another mixed with audio freq a cause for IM.? AES and The Standards do not use frequencies much above audio for THD nor IM. And then they are also filtered by LP filter. Not always indicative of the real world environment.
THx-RNMarsh
THx-RNMarsh
Given an input signal (be it a sine, or your favorite music) IMD created by speakers is indistinguishable from IMD created by an amplifier. All intermodulation products occur at the same frequencies. That's because nonlinearities (with the exception of time variant systems) cannot create non harmonic components. Therefore, "IMD from electronics map to some different frequencies than IMD from speaker drivers" is a physical impossibility.
Unless you are one of those Fourier denier (which I have reason to believe you are), then everything is possible 😀.
Well then you must believe that IMD in speakers completely masks/dominates IMD from electronics - correct?
And that IMD from audio electronics is a useless measure as it's always dominated by speaker IMD?
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That depends on what you are looking for. Some amplifiers with a SQ much praised (by reviewers and audiophiles) have IMD as large or even larger than good speakers. So it appears a large IMD in the electronics allows charging $350,000 for a pair of monoblock amplifiers, and then having very happy customers.
What I'm trying to say is that if we have a signal coming from an amplifier with no IMD, just the original signal, will this create a different IMD spectrum on the speaker drivers than an amplifier that is sending a signal with IMD tones arriving at the speaker drivers? In other words in one case we we have sum & diff tones created in the speaker drivers which are derived from signal alone - in the other case we have sum & diff tones created at the drivers which are derived from signal + IMD coming from amp.
The speaker is creating even more IMD because the signal it is transducing is original signal + IMD from electronics
Here's what Linkwitz says about Loudspeaker IMD:
"Live instruments had a space between tones, like a black background, and even en mass always remained articulate"
"if a loudspeaker was playing instead. It seems to me that the ongoing-ness of sound is one of the major problems with speakers. It shows less with recordings of a single voice with small accompaniment, so often favored by audiophiles, but in complex passages of classical orchestral music and choral works."
In other words, a sort of hash accompanies complex music from speakers compared to live (unamplified) music. From experience, this happens with electronics - the good reproduction produces less hash in the speakers & the sound is perceived as more real sounds emerge from blackness/silence - no hash over everything
Sure there are exceptions but in general electronics IMD is far below speaker IMD so I was asking if you thought any amp which measures lower IMD than speaker has inaudible IMD ?
You don't seem to understand that the electronic signal from amp that has IMD has a different spectral makeup than an amp with no IMD (I know this doesn't exist but some amps come close) - the speaker is getting a different signal & will create additional distortion sum & diff products on the new elements in the signal. This will probably translate into perceived hash where there should be silence
I'll ignore the attempted jibes - so let's try no ad-homs for some civility?
I understand perfectly, this is not what you said.
Otherwise yes, the electronics IMD can be safely ignored if it is much lower than the speaker IMD. The same rule applies for any type of distortions.
The electronics IMD that creates more IMD at the speaker is a red herring. A speaker does not amplify the input IMD, IMD adds up as any other distortion. Either the electronics IMD is much smaller than the speaker (and than it can be ignored), or is not (and then it adds up). Pick your choice.
To be be clear this is wrong, they can not be DIFFERENT frequencies. They are always the same frequencies.
So maybe I was incorrect in the way I expressed my thoughts?
On what basis are you stating it can be ignored? Are you saying lower IMD from electronics is masked psychoacoustically or why do we not perceive it?
I never said the speaker amplified IMD - I said the electronics IMD is a new element in the signal reaching the speakers & the drivers reproduce this electrical signal
if there was no IMD created in the amplifier then the signal the speaker has to handle is different.
So the speaker drive will create IMD of the original signal & will create IMD of the extra elements in the signal arriving from the amp output - those extra elements are the IMD created in the amp
I expressed it incorrectly - hope my subsequent posts clarified what I was trying to say?
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