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Bass distortion with new amp

Nov 18, 2016
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I'm gradually replacing my 20-year-old system as bits of it fail. Earlier in the year I got the Marantz CD6005, which sounded great through my old Marantz PM57 amp and JPW ML510 speakers. But then the amp blew and I bought the PM5005 to replace it. I hooked everything up and had the feeling it didn't sound quite right. Playing around, I found that pushing the volume much beyond the 9 o'clock position or turning the bass up to full causes a really unpleasant distortion on the bass in both speakers. I'm sure the speakers were capable of handling those volumes from the old amp. Any ideas?
 

AntAxon

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Jan 9, 2015
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Martin Griffiths said:
I'm gradually replacing my 20-year-old system as bits of it fail. Earlier in the year I got the Marantz CD6005, which sounded great through my old Marantz PM57 amp and JPW ML510 speakers. But then the amp blew and I bought the PM5005 to replace it. I hooked everything up and had the feeling it didn't sound quite right. Playing around, I found that pushing the volume much beyond the 9 o'clock position or turning the bass up to full causes a really unpleasant distortion on the bass in both speakers. I'm sure the speakers were capable of handling those volumes from the old amp. Any ideas?
Have you got the +/- the correct way on the speaker/amp connections?
 

shadders

Well-known member
Nov 19, 2009
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Martin Griffiths said:
I'm gradually replacing my 20-year-old system as bits of it fail. Earlier in the year I got the Marantz CD6005, which sounded great through my old Marantz PM57 amp and JPW ML510 speakers. But then the amp blew and I bought the PM5005 to replace it. I hooked everything up and had the feeling it didn't sound quite right. Playing around, I found that pushing the volume much beyond the 9 o'clock position or turning the bass up to full causes a really unpleasant distortion on the bass in both speakers. I'm sure the speakers were capable of handling those volumes from the old amp. Any ideas?
Hi,

It may not just be the amplifier that failed. Hard to tell, but can you take out the bass driver and examine the crossover? Look for anything like a blown capacitor, or the enamel on an inductor melted etc.

It could be the speaker drivers themselves, but not sure how to test, unless you have anothrr amplifier.

Regards,

Shadders.
 

davedotco

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Apr 24, 2013
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Martin Griffiths said:
I'm gradually replacing my 20-year-old system as bits of it fail. Earlier in the year I got the Marantz CD6005, which sounded great through my old Marantz PM57 amp and JPW ML510 speakers. But then the amp blew and I bought the PM5005 to replace it. I hooked everything up and had the feeling it didn't sound quite right. Playing around, I found that pushing the volume much beyond the 9 o'clock position or turning the bass up to full causes a really unpleasant distortion on the bass in both speakers. I'm sure the speakers were capable of handling those volumes from the old amp. Any ideas?
I would say that you are simply overdriving the amplifier. If you are playing 'pop' music of virtually any kind the frequency distribution means tha turning up the bass requires the same power as turning up the volume.

Ie if your amplifier output is, say, 1 watt rms, then turning the bass up full could easily lift the bass by 10dB, so your amplifier is now required to produce 10 watts. Given that all but the most compressed recordings will have peaks 10dB above average (rms), the amplifier is now required to produce 100 watts on peaks, rather beyond the capability of the PM5005.

Note. It might be damaged speakers but if the problem is the same on both and they sound ok at 'normal' levels, probably not.
 

gasolin

Well-known member
Mar 17, 2013
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Take the bassdriver out and examine the crossover WTH

The amp might play full power at 9'o clock and of course you can't just turn the bass all the way up with no distortion https://youtu.be/JhuWuTDZiuI?t=20m40s
 

shadders

Well-known member
Nov 19, 2009
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Hi,

Simply, if the bass/mid has a second order filter, then the capacitor may be the issue where the problem only occurs at high level. Who knows, so a quick check is easy, nothing difficult.

Not seen the new amp, so 9 o'clock could be 3/4 power, or 1/4 power. My Audiolab and Denon start at 7 o'clock.

Regards,

Shadders.
 

shadders

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Nov 19, 2009
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Hi,

Just checked the PM5005 picture, and 9 o'clock is less then 1/4 power, so when you state turning up the bass, I assume you mean the tone control?

Possibly a fault with the amp, but you do not know what the damage to the speakers could be from you previous amp incident.

Regards,

Shadders.
 

davedotco

New member
Apr 24, 2013
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shadders said:
Hi,

Simply, if the bass/mid has a second order filter, then the capacitor may be the issue where the problem only occurs at high level. Who knows, so a quick check is easy, nothing difficult.

Not seen the new amp, so 9 o'clock could be 3/4 power, or 1/4 power. My Audiolab and Denon start at 7 o'clock.

Regards,

Shadders.
It is nothing of the sort.

There is no direct correlation between the volume control setting and the power output.

The setting is more dependent on the input sensitivity, 200mv in this case, the output level of the CD player, over 2volts and the whim of the designer.

It is well known that many amplifiers are designed to 'get loud' very quickly in order to impress the average punter, ie if it is that loud a 9 o'clock, just think how loud it would be at 3 o'clock.

With modern pop type music it is perfectly likely that loud passages will have the amplifier delivering maximum output around 10-12 o'clock and turning the bass up high could easily bring this down to 9 o'clock, as a described above.
 

shadders

Well-known member
Nov 19, 2009
152
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davedotco said:
shadders said:
Hi,

Simply, if the bass/mid has a second order filter, then the capacitor may be the issue where the problem only occurs at high level. Who knows, so a quick check is easy, nothing difficult.

Not seen the new amp, so 9 o'clock could be 3/4 power, or 1/4 power. My Audiolab and Denon start at 7 o'clock.

Regards,

Shadders.
It is nothing of the sort.

There is no direct correlation between the volume control setting and the power output.

The setting is more dependent on the input sensitivity, 200mv in this case, the output level of the CD player, over 2volts and the whim of the designer.

It is well known that many amplifiers are designed to 'get loud' very quickly in order to impress the average punter, ie if it is that loud a 9 o'clock, just think how loud it would be at 3 o'clock.

With modern pop type music it is perfectly likely that loud passages will have the amplifier delivering maximum output around 10-12 o'clock and turning the bass up high could easily bring this down to 9 o'clock, as a described above.
Hi,

It was a generalisation, not exact science statement. If it was an exact scientific statement, then I would have stated numbers to 1 decimal places at least, with other criteria to refine the statement. The term you may be looking for is that the volume control is logarithmic, as opposed to linear. As such, there is a direct correlation between the volume control and the power, where this correlation is logarithmic. Could be linear, depends on the designers preferences.

The 200mV is not stated how it would be amplified, it just says this as an input sensitivity and the input impedance.

The manual states that a 2volt input signal will present the rated power at the speaker terminals. It does not state the volume control position for this input signal. It could be with the volume control at the full volume setting, but this would be an assumption.

The tone controls provide +/-10dB gain, so this may be the issue, turning up the bass to a maximum providing a 10dB gain at 100Hz.

Regards,

Shadders.
 

davedotco

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Apr 24, 2013
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shadders said:
davedotco said:
shadders said:
Hi,

Simply, if the bass/mid has a second order filter, then the capacitor may be the issue where the problem only occurs at high level. Who knows, so a quick check is easy, nothing difficult.

Not seen the new amp, so 9 o'clock could be 3/4 power, or 1/4 power. My Audiolab and Denon start at 7 o'clock.

Regards,

Shadders.
It is nothing of the sort.

There is no direct correlation between the volume control setting and the power output.

The setting is more dependent on the input sensitivity, 200mv in this case, the output level of the CD player, over 2volts and the whim of the designer.

It is well known that many amplifiers are designed to 'get loud' very quickly in order to impress the average punter, ie if it is that loud a 9 o'clock, just think how loud it would be at 3 o'clock.

With modern pop type music it is perfectly likely that loud passages will have the amplifier delivering maximum output around 10-12 o'clock and turning the bass up high could easily bring this down to 9 o'clock, as a described above.
Hi,

It was a generalisation, not exact science statement. If it was an exact scientific statement, then I would have stated numbers to 1 decimal places at least, with other criteria to refine the statement. The term you may be looking for is that the volume control is logarithmic, as opposed to linear. As such, there is a direct correlation between the volume control and the power, where this correlation is logarithmic. Could be linear, depends on the designers preferences.

The 200mV is not stated how it would be amplified, it just says this as an input sensitivity and the input impedance.

The manual states that a 2volt input signal will present the rated power at the speaker terminals. It does not state the volume control position for this input signal. It could be with the volume control at the full volume setting, but this would be an assumption.

The tone controls provide +/-10dB gain, so this may be the issue, turning up the bass to a maximum providing a 10dB gain at 100Hz.

Regards,

Shadders.
For my rather 'terse' comment, but this is an issue that confuses many enthusiasts.

The input sensitivity is pretty much everything in this situation, 200mv (for full output) is way too high for modern digital players or dacs which all have (real world) outputs in excess of 2volts.

Manufacturers know that the audible differences between CD players, dacs and even amplifiers are really pretty small, particularly when compared to the more obvious differences percieved by small increases in level, so they do everything in their power to make the buyer play their product just that tiny bit louder.

It is hard to over emphasise the effect of this, even when you understand what is going on, it is very difficult not to prefer the 'more powerful' combination. The downside though is the way the amplifier 'gets loud' very quickly, this makes volume settings very difficult and whilst this apparent power seems impressive initially, it really does not last.

The law of the volume control is of course up to the designer, but is rarely the major issue, 'over driving' the amp, as described above is the big issue and I am afraid the manufacturers are responsible, one of the main reasons I find mainstream components so mediocre.
 

gasolin

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Mar 17, 2013
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shadders said:
Hi,

Just checked the PM5005 picture, and 9 o'clock is less then 1/4 power, so when you state turning up the bass, I assume you mean the tone control?

Possibly a fault with the amp, but you do not know what the damage to the speakers could be from you previous amp incident.

Regards,

Shadders.
No it isn' less than 1/4 of the max power at 9 o' clock,. max power is not reached when you turn the volume knob as much as you can

12o'clock with a turntable the music is loud, the same record on a cd might in 99% of the time at 12 o'clock distort alot, play way above it's limited
 

shadders

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Nov 19, 2009
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Hi,

Marantz state that for a 2volt input signal, you obtain the rated output, which is 40watts RMS. This is with an 8ohms load.

From the picture, the volume control goes from 7 o'clock which is no sound output (actually minimal) to 5 o'clock which is the maximum gain of the amplifier. This is a angular rotation of 300degrees.

Therefore, for a 2volt input signal, and with the volume control at 5 o'clock, you will obtain an output of 40watts RMS into 8ohms.

Depending on the type of potentiometer used in the volume control, whether linear or logarithmic, the 60degrees from 7 o'clock to 9 o'clock will increase the perceived sound level significantly, but the power delivered to the load will be less than 1/2 power. My statement of 1/4 was a generalisation and an estimation. You still have 4/5 of the total rotation to go, from 9 o'clock to get to 5 o'clock.

As the original poster stated, they may have turned up the bass tone control to a maximum which +10dB at 100Hz. If we assume 1/4 power at the 9 o'clock position, then this requires a power of 10x 1/4 = 2.5x more power required than the amplifier can deliver.

Regards,

Shadders.
 

nopiano

Well-known member
Feb 15, 2009
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shadders said:
Hi,

Marantz state that for a 2volt input signal, you obtain the rated output, which is 40watts RMS. This is with an 8ohms load.

From the picture, the volume control goes from 7 o'clock which is no sound output (actually minimal) to 5 o'clock which is the maximum gain of the amplifier. This is a angular rotation of 300degrees.

Therefore, for a 2volt input signal, and with the volume control at 5 o'clock, you will obtain an output of 40watts RMS into 8ohms.

Depending on the type of potentiometer used in the volume control, whether linear or logarithmic, the 60degrees from 7 o'clock to 9 o'clock will increase the perceived sound level significantly, but the power delivered to the load will be less than 1/2 power. My statement of 1/4 was a generalisation and an estimation. You still have 4/5 of the total rotation to go, from 9 o'clock to get to 5 o'clock.

As the original poster stated, they may have turned up the bass tone control to a maximum which +10dB at 100Hz. If we assume 1/4 power at the 9 o'clock position, then this requires a power of 10x 1/4 = 2.5x more power required than the amplifier can deliver.

Regards,

Shadders.
I'm afraid, as others have tried to explain, it simply isn't the case that maximum power output will occur at 5 o'clock, as you describe above in para 3.

It could quite possibly clip much sooner than that. 5 o clock might be maximum gain, but that is not equal to maximum output.
 

shadders

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Nov 19, 2009
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nopiano said:
shadders said:
Hi,

Marantz state that for a 2volt input signal, you obtain the rated output, which is 40watts RMS. This is with an 8ohms load.

From the picture, the volume control goes from 7 o'clock which is no sound output (actually minimal) to 5 o'clock which is the maximum gain of the amplifier. This is a angular rotation of 300degrees.

Therefore, for a 2volt input signal, and with the volume control at 5 o'clock, you will obtain an output of 40watts RMS into 8ohms.

Depending on the type of potentiometer used in the volume control, whether linear or logarithmic, the 60degrees from 7 o'clock to 9 o'clock will increase the perceived sound level significantly, but the power delivered to the load will be less than 1/2 power. My statement of 1/4 was a generalisation and an estimation. You still have 4/5 of the total rotation to go, from 9 o'clock to get to 5 o'clock.

As the original poster stated, they may have turned up the bass tone control to a maximum which +10dB at 100Hz. If we assume 1/4 power at the 9 o'clock position, then this requires a power of 10x 1/4 = 2.5x more power required than the amplifier can deliver.

Regards,

Shadders.
I'm afraid, as others have tried to explain, it simply isn't the case that maximum power output will occur at 5 o'clock, as you describe above in para 3.

It could quite possibly clip much sooner than that. 5 o clock might be maximum gain, but that is not equal to maximum output.
Hi,

I stated with a 2volt input signal.

Regards,

Shadders.
 

nopiano

Well-known member
Feb 15, 2009
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shadders said:
nopiano said:
shadders said:
Hi,

Marantz state that for a 2volt input signal, you obtain the rated output, which is 40watts RMS. This is with an 8ohms load.

From the picture, the volume control goes from 7 o'clock which is no sound output (actually minimal) to 5 o'clock which is the maximum gain of the amplifier. This is a angular rotation of 300degrees.

Therefore, for a 2volt input signal, and with the volume control at 5 o'clock, you will obtain an output of 40watts RMS into 8ohms.

Depending on the type of potentiometer used in the volume control, whether linear or logarithmic, the 60degrees from 7 o'clock to 9 o'clock will increase the perceived sound level significantly, but the power delivered to the load will be less than 1/2 power. My statement of 1/4 was a generalisation and an estimation. You still have 4/5 of the total rotation to go, from 9 o'clock to get to 5 o'clock.

As the original poster stated, they may have turned up the bass tone control to a maximum which +10dB at 100Hz. If we assume 1/4 power at the 9 o'clock position, then this requires a power of 10x 1/4 = 2.5x more power required than the amplifier can deliver.

Regards,

Shadders.
I'm afraid, as others have tried to explain, it simply isn't the case that maximum power output will occur at 5 o'clock, as you describe above in para 3.

It could quite possibly clip much sooner than that. 5 o clock might be maximum gain, but that is not equal to maximum output.
Hi,

I stated with a 2volt input signal.

Regards,

Shadders.
I know, Shadders, but that simpky isn't how it works, sorry. These aren't scientific instruments, they are domestic products. I guarantee a Marantz with 2v input will clip at about 12 or 1 o'clock.
 

nopiano

Well-known member
Feb 15, 2009
288
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shadders said:
nopiano said:
shadders said:
nopiano said:
shadders said:
Hi,

Marantz state that for a 2volt input signal, you obtain the rated output, which is 40watts RMS. This is with an 8ohms load.

From the picture, the volume control goes from 7 o'clock which is no sound output (actually minimal) to 5 o'clock which is the maximum gain of the amplifier. This is a angular rotation of 300degrees.

Therefore, for a 2volt input signal, and with the volume control at 5 o'clock, you will obtain an output of 40watts RMS into 8ohms.

Depending on the type of potentiometer used in the volume control, whether linear or logarithmic, the 60degrees from 7 o'clock to 9 o'clock will increase the perceived sound level significantly, but the power delivered to the load will be less than 1/2 power. My statement of 1/4 was a generalisation and an estimation. You still have 4/5 of the total rotation to go, from 9 o'clock to get to 5 o'clock.

As the original poster stated, they may have turned up the bass tone control to a maximum which +10dB at 100Hz. If we assume 1/4 power at the 9 o'clock position, then this requires a power of 10x 1/4 = 2.5x more power required than the amplifier can deliver.

Regards,

Shadders.
I'm afraid, as others have tried to explain, it simply isn't the case that maximum power output will occur at 5 o'clock, as you describe above in para 3.

It could quite possibly clip much sooner than that. 5 o clock might be maximum gain, but that is not equal to maximum output.
Hi,

I stated with a 2volt input signal.

Regards,

Shadders.
I know, Shadders, but that simpky isn't how it works, sorry. These aren't scientific instruments, they are domestic products. I guarantee a Marantz with 2v input will clip at about 12 or 1 o'clock.
Hi,

The 2volts input producing a 40watts RMS output into 8ohms, at a THD of 0.01%. This is from the manual. I am assuming that since Marantz do not state the position of the volume control, that this is at the 5 o'clock position where the is no attenuation from the potentiometer.

An amplifier and scientific equipment are essentially the same, although the specification of the scientific instrument will be more stringent, or offer better accuracy etc.

Regards,

Shadders.
Yes, and that assumption is where the theory falls away. You are being totally logical, but that isn't how amps are designed. I won't repeat myself!

Most amps have much more gain, to deal with other lower-output sources, than they need for CD players. It's just how it is. But let's not lose any sleep over it. :)
 

shadders

Well-known member
Nov 19, 2009
152
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18,670
nopiano said:
shadders said:
nopiano said:
shadders said:
Hi,

Marantz state that for a 2volt input signal, you obtain the rated output, which is 40watts RMS. This is with an 8ohms load.

From the picture, the volume control goes from 7 o'clock which is no sound output (actually minimal) to 5 o'clock which is the maximum gain of the amplifier. This is a angular rotation of 300degrees.

Therefore, for a 2volt input signal, and with the volume control at 5 o'clock, you will obtain an output of 40watts RMS into 8ohms.

Depending on the type of potentiometer used in the volume control, whether linear or logarithmic, the 60degrees from 7 o'clock to 9 o'clock will increase the perceived sound level significantly, but the power delivered to the load will be less than 1/2 power. My statement of 1/4 was a generalisation and an estimation. You still have 4/5 of the total rotation to go, from 9 o'clock to get to 5 o'clock.

As the original poster stated, they may have turned up the bass tone control to a maximum which +10dB at 100Hz. If we assume 1/4 power at the 9 o'clock position, then this requires a power of 10x 1/4 = 2.5x more power required than the amplifier can deliver.

Regards,

Shadders.
I'm afraid, as others have tried to explain, it simply isn't the case that maximum power output will occur at 5 o'clock, as you describe above in para 3.

It could quite possibly clip much sooner than that. 5 o clock might be maximum gain, but that is not equal to maximum output.
Hi,

I stated with a 2volt input signal.

Regards,

Shadders.
I know, Shadders, but that simpky isn't how it works, sorry. These aren't scientific instruments, they are domestic products. I guarantee a Marantz with 2v input will clip at about 12 or 1 o'clock.
Hi,

The 2volts input producing a 40watts RMS output into 8ohms, at a THD of 0.01%. This is from the manual. I am assuming that since Marantz do not state the position of the volume control, that this is at the 5 o'clock position where the is no attenuation from the potentiometer.

An amplifier and scientific equipment are essentially the same, although the specification of the scientific instrument will be more stringent, or offer better accuracy etc.

I think I know what the difference is - the energy in music is spread, as such the power of a music signal is not a single tone, where the specifications are stated for a single tone.

Regards,

Shadders.
 

davedotco

New member
Apr 24, 2013
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shadders said:
Hi,

Marantz state that for a 2volt input signal, you obtain the rated output, which is 40watts RMS. This is with an 8ohms load.

From the picture, the volume control goes from 7 o'clock which is no sound output (actually minimal) to 5 o'clock which is the maximum gain of the amplifier. This is a angular rotation of 300degrees.

Therefore, for a 2volt input signal, and with the volume control at 5 o'clock, you will obtain an output of 40watts RMS into 8ohms.

Depending on the type of potentiometer used in the volume control, whether linear or logarithmic, the 60degrees from 7 o'clock to 9 o'clock will increase the perceived sound level significantly, but the power delivered to the load will be less than 1/2 power. My statement of 1/4 was a generalisation and an estimation. You still have 4/5 of the total rotation to go, from 9 o'clock to get to 5 o'clock.

As the original poster stated, they may have turned up the bass tone control to a maximum which +10dB at 100Hz. If we assume 1/4 power at the 9 o'clock position, then this requires a power of 10x 1/4 = 2.5x more power required than the amplifier can deliver.

Regards,

Shadders.
Generally speaking the input sensitivity, 200mv in this instance, is defined as the input required for full output, this is what sensitivity means.

I don't know where you get the marantz quote from, but it is clearly an error.

Based on an incorrect premise, the second highlighted part is therefore incorrect, just 200mv is sufficient to give the full rated ouput of 40watts. This is why, when driven by the 2+volts of a digital player/dac, the amplifier gets loud so quickly.

The volume control is something of a red herring in all this, it operates entirely at the whim of the designer, about the only thing you can say for certain is that if you turn it up it gets louder, thats it. The idea that a 50% setting relates to half power (with a linear pot) or to one tenth power (with a logarithmic pot) simply is not true.

The use of the bass control causes some confusion too, it is simple a frequency dependent volume control, and adjusts the gain but only at lower frequencies. Given the power vs frequency distribution of popular music, virtually all the power is at low frquencies, so boosting the bass has pretty much the same effect on the power delivered by the amp as turning up the volume.

Ie, if you boost the bass by 10dB, you have 10dB less available on the volume, it's all about gain, you have around 26dB of gain in this amplifier, if you use 10dB to boost the bass, you only have 16dB 'left' for the volume.

Note. I see your premise comes from the Marantz manual, that is clearly an error.

By definition, the full output of the amplifier will be delivered from 200mv. See above.
 

shadders

Well-known member
Nov 19, 2009
152
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18,670
davedotco said:
shadders said:
Hi,

Marantz state that for a 2volt input signal, you obtain the rated output, which is 40watts RMS. This is with an 8ohms load.

From the picture, the volume control goes from 7 o'clock which is no sound output (actually minimal) to 5 o'clock which is the maximum gain of the amplifier. This is a angular rotation of 300degrees.

Therefore, for a 2volt input signal, and with the volume control at 5 o'clock, you will obtain an output of 40watts RMS into 8ohms.

Depending on the type of potentiometer used in the volume control, whether linear or logarithmic, the 60degrees from 7 o'clock to 9 o'clock will increase the perceived sound level significantly, but the power delivered to the load will be less than 1/2 power. My statement of 1/4 was a generalisation and an estimation. You still have 4/5 of the total rotation to go, from 9 o'clock to get to 5 o'clock.

As the original poster stated, they may have turned up the bass tone control to a maximum which +10dB at 100Hz. If we assume 1/4 power at the 9 o'clock position, then this requires a power of 10x 1/4 = 2.5x more power required than the amplifier can deliver.

Regards,

Shadders.
Generally speaking the input sensitivity, 200mv in this instance, is defined as the input required for full output, this is what sensitivity means.

I don't know where you get the marantz quote from, but it is clearly an error.

Based on an incorrect premise, the second highlighted part is therefore incorrect, just 200mv is sufficient to give the full rated ouput of 40watts. This is why, when driven by the 2+volts of a digital player/dac, the amplifier gets loud so quickly.

The volume control is something of a red herring in all this, it operates entirely at the whim of the designer, about the only thing you can say for certain is that if you turn it up it gets louder, thats it. The idea that a 50% setting relates to half power (with a linear pot) or to one tenth power (with a logarithmic pot) simply is not true.

The use of the bass control causes some confusion too, it is simple a frequency dependent volume control, and adjusts the gain but only at lower frequencies. Given the power vs frequency distribution of popular music, virtually all the power is at low frquencies, so boosting the bass has pretty much the same effect on the power delivered by the amp as turning up the volume.

Ie, if you boost the bass by 10dB, you have 10dB less available on the volume, it's all about gain, you have around 26dB of gain in this amplifier, if you use 10dB to boost the bass, you only have 16dB 'left' for the volume.
Hi,

I updated my post, my mistake was assuming a single tone for the input as opposed to a reasonably wider band signal, whose power was greater than the single tone at 2volts. Apologies for that.

All data I provided was from the user manual - hence if 200mV is for full output, then the quoted 2volts for 40watts RMS is a mistake in their manual. You can download from their website. Checking hifi world they state sensitivity is tested with single tone. They also quote 200mV or 400mV is standard - so the 2volts is a mistake in the manual.

Regards,

Shadders.
 

gasolin

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Mar 17, 2013
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the 2v is only for signal noise CD, TUNER, NETWORK, RECORDER : 103 dB (2 V input, Rated output)

Input sensitivity/Input impedance

PHONO (MM) : 2.2 mV/47 kΩ/kohms CD, TUNER, NETWORK, RECORDER : 200 mV/20 kΩ/kohms

Maximum allowable PHONO input level (1 kHz) MM : 110 mV

the manual on page 41 say 100hz +10 but doesen't say anything about q

if 100hz is +10db and 90/110hz is only 2 db louder when 100hz is + 10db or 80-120hz with an avarage of 8db peaking at 10db at 100hz
 

davedotco

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Apr 24, 2013
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gasolin said:
the 2v is only for signal noise CD, TUNER, NETWORK, RECORDER : 103 dB (2 V input, Rated output)

Input sensitivity/Input impedance

PHONO (MM) : 2.2 mV/47 kΩ/kohms CD, TUNER, NETWORK, RECORDER : 200 mV/20 kΩ/kohms

Maximum allowable PHONO input level (1 kHz) MM : 110 mV

the manual on page 41 say 100hz +10 but doesen't say anything about q

if 100hz is +10db and 90/110hz is only 2 db louder when 100hz is + 10db or 80-120hz with an avarage of 8db peaking at 10db at 100hz
The sensitivity is way too high for sensible use, 500mv is a sensible minimum but I personally would prefer around 750mv to 1 volt. There are a few legacy components that need a higher sensitivity (say 300-400mv), but they are getting less by the day.

I do not know this for a fact (in the case of the marantz) but most tone controls follow the Baxandal model and pivot around 1kHz. Something like this...



This shows clearly how the the whole bass region is affected by the bass control and given the power distribution in modern popular music boosting the bass is virtually the same, power wise, as turning up the volume by the same amount.
 

shadders

Well-known member
Nov 19, 2009
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18,670
gasolin said:
the 2v is only for signal noise CD, TUNER, NETWORK, RECORDER : 103 dB (2 V input, Rated output)

Input sensitivity/Input impedance

PHONO (MM) : 2.2 mV/47 kΩ/kohms CD, TUNER, NETWORK, RECORDER : 200 mV/20 kΩ/kohms

Maximum allowable PHONO input level (1 kHz) MM : 110 mV

the manual on page 41 say 100hz +10 but doesen't say anything about q

if 100hz is +10db and 90/110hz is only 2 db louder when 100hz is + 10db or 80-120hz with an avarage of 8db peaking at 10db at 100hz
Hi,

Yes, there is a mistake in the manual, above the 2volt specification for the same inputs it states 200mV.

Regards,

Shadders.
 

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