Sorry this is a bit OT but why do people say that a class A amp is better for some genre than a class AB/D if the wattage is equal?
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Output stage : Wiim Amp vs (disappointing) Wiim Amp Ultra
- Thread starter Emilio75
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Sorry this is a bit OT but why do people say that a class A amp is better for some genre than a class AB/D if the wattage is equal?
Svend P
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It's another Audiophile myth. More here
Amplifier power: Class A, AB vs D
I have owned a lot of powerful amps: Krell, McCormack, Aragon, Bryston, etc. Some weighed close to 100 lbs. Can a lightweight Class D amplifier with the same wattage rating drive a speaker just as well as a behemoth Class A or AB amp? Or is there something about current, capacitor reserve, etc...
www.audiosciencereview.com
It's another Audiophile myth. More here
Amplifier power: Class A, AB vs D
I have owned a lot of powerful amps: Krell, McCormack, Aragon, Bryston, etc. Some weighed close to 100 lbs. Can a lightweight Class D amplifier with the same wattage rating drive a speaker just as well as a behemoth Class A or AB amp? Or is there something about current, capacitor reserve, etc...
Ahh okay, so the power amps only job is to provide clean/low noise/distortion power, can it be too fast for the track mastering? Since I assume tracks are mastered under the assumption that they will be listened to on a certain banding of equipment?
Not sure im explaining myself very well but hopefully you understand!
RexrothPigeon
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No. Imagine mastering for one specific colored amp. That would be insane. (It's not possible to master for "tube amps" as a class because there is no one sound color they share. They can even be as transparent and neutral as solid state.)
I think it's called damping? How quickly the amp moves/stops the speaker
Sorry I meant banding as in a range that a system that the average joe public would have, I only ask as I remember listening to a video on YT concerning poor methods of mastering in relation to speakers as in a normal listener wouldnt have a sub or beryllium tweeters....etc.
It makes sense the way you explained it, thank you!
Sorry I meant banding as in a range that a system that the average joe public would have, I only ask as I remember listening to a video on YT concerning poor methods of mastering in relation to speakers as in a normal listener wouldnt have a sub or beryllium tweeters....etc.
It makes sense the way you explained it, thank you!
By too fast, I meant damping factor, as my logic was that some speakers might be tuned for a value...etc, found this thread: https://www.audiosciencereview.com/...-damping-factor-and-why-is-it-important.1257/ - one of the technical contributors describes this as "These affects can be audible and are certainly measurable."
As I understand it the higher the damping factor of an amp the better. Not a measurement of speed, but of ability to control drivers.
I am surprised to see the web mention these values:
WiiM amp / amp Ultra / Vibelink - 94
Yamaha A-S301 - 210
3e audio A7 - ~400
Purifi 1ET6525SA - beyond 100k
Just some amps I use.
I would have thought of class D to generally exceed class AB, based on absolutely nothing, and obviously wrong.
I am surprised to see the web mention these values:
WiiM amp / amp Ultra / Vibelink - 94
Yamaha A-S301 - 210
3e audio A7 - ~400
Purifi 1ET6525SA - beyond 100k
Just some amps I use.
I would have thought of class D to generally exceed class AB, based on absolutely nothing, and obviously wrong.
Damping factor is irrelevant if it's more than about 10. Maybe 20 at a push.
- Thread Starter
- #50
Hi,
Today I purchased a Tangent Ampster BT III. I got it for 130€ instead of 200€. Class D, 2x50W into 4R.
Life is back in my Tannoy. Rythm, punch, freedom… And I recognize each and every bass pattern I know by heart among dozens of tracks. Sort-of back to normal. Similar feeling as with the Marantz CR610.
All of this using BT lossy AAC from my iPhone. No EQ of course.
I’m happy to have found this sound again on a recent Class D design. This reinforces my conviction that THD (with high damping factor) alone is not sufficient to assess an amplifier, and that the current matters too, together with the complex part of RLC. After all, the mechanical force that moves the speaker cone is proportional to the current, not to the voltage.
Next step is to purchase a Wiim Ultra and use RoomFit, which I already miss. And benefit from HiRes.
Last, I’ll probably try a Hypex nCore, which I expect a lot from - maybe I’ll get the best of both worlds. And of course to benefit more power for peaks.
TBC
Today I purchased a Tangent Ampster BT III. I got it for 130€ instead of 200€. Class D, 2x50W into 4R.
Life is back in my Tannoy. Rythm, punch, freedom… And I recognize each and every bass pattern I know by heart among dozens of tracks. Sort-of back to normal. Similar feeling as with the Marantz CR610.
All of this using BT lossy AAC from my iPhone. No EQ of course.
I’m happy to have found this sound again on a recent Class D design. This reinforces my conviction that THD (with high damping factor) alone is not sufficient to assess an amplifier, and that the current matters too, together with the complex part of RLC. After all, the mechanical force that moves the speaker cone is proportional to the current, not to the voltage.
Next step is to purchase a Wiim Ultra and use RoomFit, which I already miss. And benefit from HiRes.
Last, I’ll probably try a Hypex nCore, which I expect a lot from - maybe I’ll get the best of both worlds. And of course to benefit more power for peaks.
TBC
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No thanks.
RandomEar
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The current is a consequence of the voltage. A speaker is not a perfect resistive load, but nonetheless: If the amp can't deliver the current, it also won't deliver the voltage. And as explained to you multiple times, the power output of the Wiim Amp was not the problem because your setup and listening volume did not require relevant amounts of power which means it did not get remotely close to any current limit. The Wiim amp also "delivers the current" because the measurements show it delivers the power (= voltage x current).
You're making up some totally constructed problem in your head which has no relation to what actually happens in your system. Please let us know what happens the second you add the Wiim Ultra and activate room correction - I'm pretty sure I know what's going to happen.
Humans in general are extremely unreliable for information. Eye witness testimony while often used can be extremely unreliable. Our brain is amazing and can do crazy things like make us think things happened in ways they didn't. The fact it has a huge impact on audio is really unintuitive for most people but not surprising.
It's like reading the book before you watch the movie version.
I would be careful to compare anything that way. Just a very lowtek source.
- Thread Starter
- #57
A speaker is a RLC load. R is clear. I’m talking about L and C. Phase. The complex part (i2=-1). Current flowing when voltage is zero, current not flowing when voltage is high. Because yes, it does happen, depending on L and C, and the power amp must be ready for that.
Is there any loudspeaker manufacturer providing inductive curve in Henry and capacitive curve in Farad together with the resistive curve in Ohm ?
Is there any speaker review drawing such curves ?
Is there any power amp manufacturer (especially high-efficiency non-linear Class D amps) providing output response on inductive and capacitive loads, together with the max output power on a resistive load ?
Is there any amp review including tests on inductive and capacitive loads ?
I’d be interested in such information, If any of you has links to share.
RandomEar
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Amir sometimes uses his reactive load box for amplifier reviews like this one. As you can see, the capacitive and inductive loads are - in general - much less problematic than low resistance.
I'll repeat that you are making up a problem in your mind without there being any evidence at all that this supposed problem is related to the experience you report with the WiiM in any way. The most likely explanation remains that the room correction / EQ just sound wrong to you...
EDIT: Luckily, there is a reactive load test for the Fosi V3 Mono, which uses the same dual TPA3255 setup as the WiiM Amp Ultra. As you can see, that chip duo does not care at all what you throw at it.
I'll repeat that you are making up a problem in your mind without there being any evidence at all that this supposed problem is related to the experience you report with the WiiM in any way. The most likely explanation remains that the room correction / EQ just sound wrong to you...
EDIT: Luckily, there is a reactive load test for the Fosi V3 Mono, which uses the same dual TPA3255 setup as the WiiM Amp Ultra. As you can see, that chip duo does not care at all what you throw at it.
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The WiiM Vibelink review also has some numbers to offer.
That is the TPA325x design they did prior to the WiiM Amp Ultra. It features one amp chip whereas the Ultra has two. Both things as far as I know.
The Vibelink is not too popular, but I find it's performance with digital in to it's ES9039 DAC superb. I wouldn't trade the Ultra streamer/Vibelink combo for the Amp Ultra.
That is the TPA325x design they did prior to the WiiM Amp Ultra. It features one amp chip whereas the Ultra has two. Both things as far as I know.
The Vibelink is not too popular, but I find it's performance with digital in to it's ES9039 DAC superb. I wouldn't trade the Ultra streamer/Vibelink combo for the Amp Ultra.
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