NCORE MP Build using Ghentaudio Kit.

[HammerSandwich]

But I think I'm not hitting the max amplification with the max output from the E30 (a little over 2v), because I can go to -10 dB on the E30 without any issue and -5dB is uncomfortably loud but not distorting or louder than my 2x90W Marantz could do. Doesn't feel like I can go up to 200W like this.

Because 90 -> 200W is just slightly more than +3dB and you have another +5dB from the E30, I do not understand the problem.

 

[Koeitje]

Because 90 -> 200W is just slightly more than +3dB and you have another +5dB from the E30, I do not understand the problem.

Like I said: there is no real problem . I just wanted to know if this was caused by the RCA connection and the amplifier expecting a higher voltage to reach maximum amplification. I do also understand that for +3dB you need to double the power, but I'd smoke my speakers if I run at maximum power anyway . All this stems from me being surprised I had to turn up the volume on my DAC so much.

 

[ironhorse128]

The pops are a widespread issue. I also have it on power up and power down on my Hypex/Ghent amp. However, it is not that loud at all, so no real concern there for me.

I have a pair of AUDIOPHONICS MPA-M250NC (NC250 based) and I do not have any pops at power up nor at power down. I use RCAs at the moment. I guess I am lucky.

 

[mika91]

I have a pair of AUDIOPHONICS MPA-M250NC (NC250 based) and I do not have any pops at power up nor at power down. I use RCAs at the moment. I guess I am lucky.

Maybe mono modules are less affected by pops

 

[Koeitje]

Maybe mono modules are less affected by pops

NC400 are mono...

I noticed one of mine pops when turning is on/off and the other doesn't.

 

[kn0ppers]

NC400 are mono...

I noticed one of mine pops when turning is on/off and the other doesn't.

Both are of the same PCB revision and connected to the same power supply? (I don't know if there are even different PCB revisions, but if there are, it could be an explanation...)

 

[Koeitje]

Both are of the same PCB revision and connected to the same power supply? (I don't know if there are even different PCB revisions, but if there are, it could be an explanation...)

I bought these second hand and I can't figure out how to remove the front plate to be able to remove the top completely (all I could see is that the speaker terminal cables are twisted well enough). They were build at the same time, but I can't check PCB versions right now. If I figure out how to remove the front plate I will let you know .

Edit: I just turned them on without the source on and none of them popped. So who the fuck knows.

 

[JimB]

I bought these second hand and I can't figure out how to remove the front plate to be able to remove the top completely....

A Hypex case has two tiny allen screws under the front edge of the faceplate. You back them out (at least a few turns), then angle the bottom of the faceplate out, then lift it up and off.

 

[Koeitje]

A Hypex case has two tiny allen screws under the front edge of the faceplate. You back them out (at least a few turns), then angle the bottom of the faceplate out, then lift it up and off.

Ah I see those, didn't even realise they were allen screw....they are so tiny. I probably have something I can use in my quadcopter toolbox.

Edit: yep got a 1.5 that fits

 

[mika91]

I just ordered a speaker protection module.
Not enough space in the ghent audio case to integrate it, so I'll try to use it externally (and be sure to power off the speaker protection power supply before powe the amp off)
Hope this will help... my nc122mp is stored on a shelf for now

 

[GentleEars]

I bought AUDIOPHONICS MPA-S252NC XLR, the stereo amp, and it doesn't pop. I use it with TOPPING DX7 PRO with a cheap pair of XLR cables from Audiophonics.fr.

 

[sfabio]

I bought AUDIOPHONICS MPA-S252NC XLR, the stereo amp, and it doesn't pop. I use it with TOPPING DX7 PRO with a cheap pair of XLR cables from Audiophonics.fr.

What kind of speakers do You have? With passive low sensitivity speakers the pop is inaudible, I have a 110 dB mid-high without crossover, the pop is very loud!

 

[MenloBob]

What kind of speakers do You have? With passive low sensitivity speakers the pop is inaudible, I have a 110 dB mid-high without crossover, the pop is very loud!

My horns are 110db too and moreover they are direct connected to my 122MP. I've been thinking of building an aurduino solution for this. In the interim I just don't turn the amp off

 

[mika91]

My horns are 110db too and moreover they are direct connected to my 122MP. I've been thinking of building an aurduino solution for this. In the interim I just don't turn the amp off

Same idea here.
I've ordered an Arduino nano, and will try to implement a simple startup/shutdown sequence, remotely driven, using mute and standby pins.

 

[sfabio]

Same idea here.
I've ordered an Arduino nano, and will try to implement a simple startup/shutdown sequence, remotely driven, using mute and standby pins.

It seems that it doesn't work: #91 The only thing that can avoid pops is a relay that disconnects the speakers from the amplifier. But luckily the pops are only annoying, not dangerous. Since the pop on power on is much less strong than the pop on power off, maybe just muting the amp before turning it off is enough

 

[mika91]

According to this previous post, the pop occurs when the mute is released.
I don't have power on pop (only power off) so maybe un-muting will be pop free with my amp...

 

[sfabio]

According to this previous post, the pop occurs when the mute is released.
I don't have power on pop (only power off) so maybe un-muting will be pop free with my amp...

Maybe! Please keep us informed

 

[JimB]

It seems that it doesn't work: #91 The only thing that can avoid pops is a relay that disconnects the speakers from the amplifier. But luckily the pops are only annoying, not dangerous. Since the pop on power on is much less strong than the pop on power off, maybe just muting the amp before turning it off is enough

IF there is a DC offset on the output of the amp while on, you will have a sound when connecting and disconnecting, no matter how you do it.

 

[HammerSandwich]

The only thing that can avoid pops is a relay that disconnects the speakers from the amplifier.

Or a MOSFET, as on @tomchr's Guardian boards.

 

[sfabio]

IF there is a DC offset on the output of the amp while on, you will have a sound when connecting and disconnecting, no matter how you do it.

I've neither the equipment nor the ability to measure this, maybe Alan @March Audio can help us to understand why there are these "pops" in our systems. But IF there is a DC offset when on, may it not be there when muted? It seems that there are no pops turning it off when muted