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Bass distortion with new amp

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gasolin

Well-known member
Mar 17, 2013
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the 200mv is input sensitivity, the 2v is used to test how god the signal,noise ratio is

nothing wrong with that, theres just a big difference between the how loud music is with a turntabel and cplayer playing the same music with the voulmeknob at the same position
 

shadders

Well-known member
Nov 19, 2009
152
88
18,670
gasolin said:
the 200mv is input sensitivity, the 2v is used to test how god the signal,noise ratio is

nothing wrong with that, theres just a big difference between the how loud music is with a turntabel and cplayer playing the same music with the voulmeknob at the same position
Hi,

It is misleading. If sensitivity is implemented with the volume control at maximum (no attenuation from the volume control) and a single tone at 1kHz (http://www.hi-fiworld.co.uk/amplifiers/75-amp-tests/150-sensitivity.html), and Marantz are stating 200mV as their input sensitivity, then the 2volts is not possible. A 2volt signal will overdrive the amplifier.

If Marantz are reducing the volume control to a known value where the 2volt input signal does indeed produce 40watts RMS into an 8ohm load, then the provided S/N is not commensurate with the actual S/N of an input that is driven by a signal at 200mV.

If anything, they should have provided the S/N at the 200mV sensitivity.

Regards,

Shadders.
 

steve_1979

Well-known member
Jul 14, 2010
231
7
18,795
Most modern amplifiers will have reached their maximum limit and started clipping before they reach 12 o'clock on the volume dial. It's just a con that the designers use to make an amplifier seem like it's more powerful than it really is so that more people buy it.

(Yes I know there are several variables such as the input sensitivity, the dynamic range of music being played, whether bass boosting equalization is used and the resistance of the speakers used but as a generalisation the above comment will be correct 99% of the time)
 

shadders

Well-known member
Nov 19, 2009
152
88
18,670
steve_1979 said:
Most modern amplifiers will have reached their maximum limit and started clipping by the time they reach 12 o'clock on the volume dial. It's just a con that the designers use to make the amplifier seem like it is more powerful than it really is so that more people will buy it.

(Yes I know there are several variables such as the input sensitivity, the dynamic range of music being played, whether bass boosting equalization is used and the resistance of the speakers used but as a generalisation the above comment will be correct 99% of the time)
Hi,

This would be subject to the source component. If a tuner had a maximum output of 200mV, then you could turn the volume to a maximum without clipping.

The misleading aspect here is the S/N ratio. The clipping will occur early since the sensitivity is reasonably high, and the majority of the sources exceed the 200mV sensitivity.

Regards,

Shadders.
 

davedotco

New member
Apr 24, 2013
20
0
0
muljao said:
Where does this leave Chord DACS often having a 3v line level
Red book standard is 2 volts, a lot of player/dac manufacturers give their products a little more output. Given the tiny difference between competent dacs a small increase in volume, one sufficiently small not to be percieved as such, will make that product seem clearer, sharper, more focussed etc.

Chord use proprietory dac technology which means it may sound a little different to those using the 'usual' chip sets. Make sure it is the loudest product on demo and you are home and hosed.
 

gasolin

Well-known member
Mar 17, 2013
732
118
19,070
shadders said:
gasolin said:
the 200mv is input sensitivity, the 2v is used to test how god the signal,noise ratio is

nothing wrong with that, theres just a big difference between the how loud music is with a turntabel and cplayer playing the same music with the voulmeknob at the same position
Hi,

It is misleading. If sensitivity is implemented with the volume control at maximum (no attenuation from the volume control) and a single tone at 1kHz (http://www.hi-fiworld.co.uk/amplifiers/75-amp-tests/150-sensitivity.html), and Marantz are stating 200mV as their input sensitivity, then the 2volts is not possible. A 2volt signal will overdrive the amplifier.

If Marantz are reducing the volume control to a known value where the 2volt input signal does indeed produce 40watts RMS into an 8ohm load, then the provided S/N is not commensurate with the actual S/N of an input that is driven by a signal at 200mV.

If anything, they should have provided the S/N at the 200mV sensitivity.

Regards,

Shadders.
On most cplayer the output is 2 volt, im very shure they have use a cdplayer for the signal/noise ratio, other than that i don't know how thay have measured the signal,noise ratio
 

gasolin

Well-known member
Mar 17, 2013
732
118
19,070
shadders said:
steve_1979 said:
Most modern amplifiers will have reached their maximum limit and started clipping by the time they reach 12 o'clock on the volume dial. It's just a con that the designers use to make the amplifier seem like it is more powerful than it really is so that more people will buy it.

(Yes I know there are several variables such as the input sensitivity, the dynamic range of music being played, whether bass boosting equalization is used and the resistance of the speakers used but as a generalisation the above comment will be correct 99% of the time)
Hi,

This would be subject to the source component. If a tuner had a maximum output of 200mV, then you could turn the volume to a maximum without clipping.

Regards,

Shadders.
No, you don't know when an amp reaches max power with a source that has an output of 200mv, you just asume it's possible to turn the volume knob all the way with an output of max 200mv.

what about a cd or lp where all sounds are loud all the time og thare a huge dynamig range because of how the cd/lp is recorded
 

shadders

Well-known member
Nov 19, 2009
152
88
18,670
gasolin said:
shadders said:
steve_1979 said:
Most modern amplifiers will have reached their maximum limit and started clipping by the time they reach 12 o'clock on the volume dial. It's just a con that the designers use to make the amplifier seem like it is more powerful than it really is so that more people will buy it.

(Yes I know there are several variables such as the input sensitivity, the dynamic range of music being played, whether bass boosting equalization is used and the resistance of the speakers used but as a generalisation the above comment will be correct 99% of the time)
Hi,

This would be subject to the source component. If a tuner had a maximum output of 200mV, then you could turn the volume to a maximum without clipping.

Regards,

Shadders.
No, you don't know when an amp reaches max power with a source that has an output of 200mv, you just asume it's possible to turn the volume knob all the way with an output of max 200mv.

what about a cd or lp where all sounds are loud all the time og thare a huge dynamig range because of how the cd/lp is recorded
Hi,

From the sources linked to above, sensitivity is defined as the input signal which causes the maximum rated power output where the volume control is at a maximum also. So, any other input which is higher will drive the amplifier into saturation if the volume is at its maximum.

Marantz have calibrated/designed their inputs with 200mV sensitivity. If you input a 2volts signal you will have to reduce the volume to achieve the 40watts rated power with THD at 0.01%. If the signal has a 200mV maximum, then you can turn the volume to a maximum and achieve the 40watts rated power output.

Regards,

Shadders.
 

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