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WolfX700 Measurement of Topping A90 Headphone Amp

JohnYang1997

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What are equivalent A90’s outputs ?
16Ohm 7600mW @0.1% THD
32Ohm 6400mW @0.1% THD
300Ohm 1000mW @0.1% THD
600Ohm 500mW @0.1% THD

BTW there's no such thing as Watts RMS. The term doesn't exist.
 

JohnYang1997

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MC_RME

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If you want to make clear to your customers that you don't try to fool them with self-defined or phantasy power values then the term RMS power is as widespread as valid. Sure an additional THD value is useful as well.
 

JohnYang1997

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If you want to make clear to your customers that you don't try to fool them with self-defined or phantasy power values then the terrm RMS power is as usual as valid. Sure an additional THD value is useful as well.
The term "RMS power" doesn't exist. The equivalent of "RMS power" is called real power and can be the same as average power.
What does RMS power mean? Let's say you take instantaneous power derived from instantaneous voltage and current. And you take RMS of that power. What does it mean? It doesn't have any meaning.
Search for "misunderstanding watts RMS". Other people have explained it better than me. So I won't verbose on this one.
 

yahrightthere

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https://www.reddit.com/r/AVexchange/comments/gfjgeo/usco_h_bottlehead_crack_massdrop_cthsdac_massdrop/

Listed only a few hours ago. $250 shipped. It's a race to the bottom when you guys just can't stop buying gear!
Thank you very much again Mister Spirit in the sky man,
aww common Jerry wouldn't have been like that, I've not bought any gear since them fancy throw-away active speakers, which BTW I really like once they were broke in & placed as good as i could get them.
I did get a SMSL SU-8 to go with them but they made my speakers pop so i sent it back.
BTW what's wrong with buying gear?
 

mt196

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babak147

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I was hoping for a 449 also for us Europeans. A lot of Topping products are sold even through Amazon, and they are at the same price converted in € as everyone else in the world. Let's hope this is just the initial price and it will get a bit down
The website says 415.83 € tax excl. , That's $450 USD.
 

babak147

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No wait, I was saying I hope it will sell at 449 tax included, I am not acquainted thinking of prices with tax excluded, probably because I live in EU and not in the US where usually VAT must be added to prices :D
Well , now it says:
499,00 €tax incl.
415,83 € tax excl.
 

Hemi-Demon

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MC_RME

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The term "RMS power" doesn't exist. The equivalent of "RMS power" is called real power and can be the same as average power.
What does RMS power mean? Let's say you take instantaneous power derived from instantaneous voltage and current. And you take RMS of that power. What does it mean? It doesn't have any meaning.
Search for "misunderstanding watts RMS". Other people have explained it better than me. So I won't verbose on this one.

After changing my Google search results from German to English I finally found the documents that explains what you mean. Sorry, must be a bit part of the language barrier. I now see what you mean and while basically you are right it assumes that someone understood 'RMS Power' the wrong way. I doubt that this is the case.

For other interested readers it all boils down to this (quote):

It should be noted that the term “RMS power” is (mis)used in the consumer audio industry. In that context, it means the average power when reproducing a single tone, but it’s not actually the RMS value of the power.

Quote 2: Almost every manufacturer, distributor, advertiser in the world involved in selling domestic audio equipment - and more than a few hi-fi magazines! - uses the term 'watts RMS'...

Exactly. It serves its purpose well. One can't sell stuff that is 'average'.
 

DDF

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It's just a wrong term. Correct terms are continuous power, average power etc. Peak power is also legit term. Using continuous power is correct but still meaningless. One can use square wave for that power. Simplest and meaningful term is xxx Watts at 0.1% THD at 1khz.

This was a pet peeve of one of my electrical engineering professors. Power is defined as an average value calculated as the product of Vrms and Irms. There is no "rms power". What is called "peak power" is the maximum average power that can be delivered over some arbitrarily defined short time window into a defined load impedance.

In a hobby where most manufacturers dont bother to define the distortion or frequency over which the spec applies, its become a number stripped of much meaning. The power difference at 0.1% vs 10% can be several times
 
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