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are 4 ohm cabs technically "better" than 8 ohm cabs?

#82
agedhorse said:
Not true. Amps without output impedance matching will deliver different power with different impedance.


Not true. With tube amps, output impedance matching matches the load impedance (2/4/8/16 ohms) to the output tubes by changing the matching transformer's ratio taps. The plate load remains constant due to these different ratios.
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I thought that the amp did the same thing it always did, but because of the impedances, output was higher or lower as an end result. You're saying that when you hook up different loads, the amplifier works in an entirely different manner? Not just cut or increased ouput as a result of changed impedance? Actually, that kinda makes sense with minimums and all. But, can you explain what actually happens?
 
#83
JeezyMcNuggles said:
I thought that the amp did the same thing it always did, but because of the impedances, output was higher or lower as an end result. You're saying that when you hook up different loads, the amplifier works in an entirely different manner? Not just cut or increased ouput as a result of changed impedance? Actually, that kinda makes sense with minimums and all. But, can you explain what actually happens?
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Solid state used to be easy to explain. Output voltage is independent of the impedance load. I don't why it is so much less simple with Class D.

Tube amps output transformers have taps to optimise the interface between the tube side and the cab side. The amp provides contant current to the amp side of the output transformer and the selection of windings on the cab side together with the impedance added by the cabinet keeps the situation stable. Maybe I could have been an electrical engineer, Agedhorse might differ.
 
#85
BadExample said:
I don't see any difference.
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There is no difference!

Where there is difference is in the loss curves and the ability of the amp to tightly integrate with the power supply, which allows us options that we could only dream of before.
 
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#89
Downunderwonder said:
Solid state used to be easy to explain. Output voltage is independent of the impedance load. I don't why it is so much less simple with Class D.

Tube amps output transformers have taps to optimise the interface between the tube side and the cab side. The amp provides contant current to the amp side of the output transformer and the selection of windings on the cab side together with the impedance added by the cabinet keeps the situation stable. Maybe I could have been an electrical engineer, Agedhorse might differ.
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Thank you. I did want to hear it from @agedhorse though. Hahaha, now it's kinda started another wit sesh huh?
 
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#92
BadExample said:
Why would you want to gain knowledge from a very well respected and experienced engineer when you have ME??? :laugh::roflmao::laugh::thumbsup:
ME???
Uh, yeah, wait for his response.
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Truth though, people learn from me more than anyone else on the web.




Follow my name, and you'll find 20 answers to questions you've never even thought about asking.
 
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#96
Downunderwonder said:
Class D amps seem to get a significantly less than double the 8 ohm power rating at 4 ohm. I guess they distort more easily at the bleeding edge of output power than the older stuff.
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Not true. In fact the class D amp in the Subway (for example) delivers exactly double the 8 ohm rating at 4 ohms.

It has nothing to do with the amplifier class, it has to do with the power supply being regulated.

Line frequency (lead sled) supplies almost always deliver less than double the power into half the load impedance irregardless of class, because they are not regulated.
 
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#97
JeezyMcNuggles said:
Thank you. I did want to hear it from @agedhorse though. Hahaha, now it's kinda started another wit sesh huh?
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A solid state amp (of all classes) acts more like a solid voltage source and behaves in accordance with ohm's law with no source impedance. A tube amp's source impedance acts less like zero ohms source impedance even when well matched.
 
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#98
agedhorse said:
Not true. In fact the class D amp in the Subway (for example) delivers exactly double the 8 ohm rating at 4 ohms.

It has nothing to do with the amplifier class, it has to do with the power supply being regulated.

Line frequency (lead sled) supplies almost always deliver less than double the power into half the load impedance irregardless of class, because they are not regulated.
Click to expand...
Subway might be the exception but I am pretty sure most of the rest of the micro bass amps don't have such good power supplies if that's what's up.
 
#100
Entertaining thread
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