Hypex Ncore

Status
Not open for further replies.
Lastly, is anyone NOT grounding the IEC Input to the chassis at all and if so, is this a safe method to use (ie... not getting shocked when hands touch the chassis)? Is this a good approach to lower the chances of ground loops entering the signal chain?

It is a good approach, and it is the recommended way to do it, but only if you know the implications of the phrase "class II construction".
 
Ooops...I forgot to ask a few more things in my last post.

Given the scenario I described in my previous post where the build is a Dual Mono type in the same chassis, what is the best way to connect the ground wires from the NC400 modules? Should each NC400 be grounded to the metal foot of its partner SMPS600 amp that is feeding it or should a more "common" ground be established that ties both NC400's & both SMPS600's to a central point?

Is it safe to assume that the XLR Inputs should just be grounded directly to the back panel near where they enter the chassis?

Lastly, is anyone NOT grounding the IEC Input to the chassis at all and if so, is this a safe method to use (ie... not getting shocked when hands touch the chassis)? Is this a good approach to lower the chances of ground loops entering the signal chain?

Thanks again.

I'd say always think of safety first and always connect safety ground.

Grounding the chassi doesn't create a ground loop either, connecting Pin1 to chassi is just extending the cables shield to include the chassi and isn't connected to signal ground. Even if you use RCA the only point where the single ended connection has to be connected to signal ground is at the DAC / Preamp side.
 
So is it correctly understood that you cannot choose "all-active" operation because it only goes active when you need more signal than what the source produce ? -Which in practice would be the same as just calling it a passive pre...
From your description I somehow understood that you actually could choose to run it in all active mode too...

Well, it's a buffered passive design which gives you the possibility to go active if you need really a lot of juice to bang your ears
 
"Patrik Bostrom, currently the most advanced Class D engineer in Europe and CTO Of Abletec, went beyond Bruno's capability with further advanced Class D engineering and developed recently, a linear loop technology known as AMS, (Adaptive modulation Servo), which is phase shift modulation, eliminating all feedback in the circuits, rather than pulse width modulation, which has been around for forty years. D-Sonic uses power modules from Abletec. The new in house switching module designed by Audio Research, achieves the same results as Abletec."

I just read this and am surprised to see that I have such a strong supporter in New Jersey :) Nevertheless, I must say that I hardly see myself as the most advanced class D engineer in Europe even though AMS is quite simple and powerful. Also, just as someone else wrote before me, AMS has a lot of feedback but the input signal does not pass through the error amplifier and hence is not affected by it's transfer function giving a first order transfer function of the complete system.

I do become curious to learn more about Audio Research's class D technology. Has someone posted anything about that? For example some measurements of frequency response and linearity?
 
"Patrik Bostrom, currently the most advanced Class D engineer in Europe and CTO Of Abletec, went beyond Bruno's capability with further advanced Class D engineering and developed recently, a linear loop technology known as AMS, (Adaptive modulation Servo), which is phase shift modulation, eliminating all feedback in the circuits, rather than pulse width modulation, which has been around for forty years. D-Sonic uses power modules from Abletec. The new in house switching module designed by Audio Research, achieves the same results as Abletec."

I just read this and am surprised to see that I have such a strong supporter in New Jersey :) Nevertheless, I must say that I hardly see myself as the most advanced class D engineer in Europe even though AMS is quite simple and powerful. Also, just as someone else wrote before me, AMS has a lot of feedback but the input signal does not pass through the error amplifier and hence is not affected by it's transfer function giving a first order transfer function of the complete system.

I do become curious to learn more about Audio Research's class D technology. Has someone posted anything about that? For example some measurements of frequency response and linearity?

First the disclaimer. I am using Hypex and do know Abletec very well.

Patrick
Can you tell us where you got that quote from and who is was in New Jersey?

Thank you.
 
Wow!....
DS450M Class D mono amp has a power reserve of 1368 joules of energy, way beyond the power reserve in the Merrill Veritas or the new upcoming M1 amps from Hypex coming out in June. The DS450M has over 176,000 microfards of capacitor storage. The large block transformer, choke regulator, and the Class D switching device in each DS450M amp are in house custom designs exclusive only to Audio Research.

why have used this big capacitors bank?
Mr.Push maybe know..
regards
 
Choke regulator? If that means a choke-input PSU, it's exactly the wrong thing for class-D -- at low output powers the supply voltage will rise to what a capacitor-input PSU would deliver, but at high currents the supply will drop to what a typical choke supply does, typically 0.7 the cap-input's rating.

And 175000 uF means lots of stray inductance before the switching transistors unless AR made sure they have scads of decoupling right at the devices. McCormack amplifiers didn't even have main filter caps -- they placed smaller caps at each output transistor, to apparently good effect.
 
Choke regulator? If that means a choke-input PSU, it's exactly the wrong thing for class-D -- at low output powers the supply voltage will rise to what a capacitor-input PSU would deliver, but at high currents the supply will drop to what a typical choke supply does, typically 0.7 the cap-input's rating.

Not necessarily -apparently Hypex SMPS600 deploys chokes on the HV rails too...
 
i experience a problme with my ncore
when i,m turning it on..the led are turning on nad then turned off and it doesn work at alla
has anyone experienc e something like that?

The first thing to check for is a shorted output (maybe just a stray strand of your speaker wire?). If you are really sure there is no short on the output, I suggest contacting hypex, as there have been some nc400's with the overvoltage protection set to slightly too sensitive. It can be recalibrated, but it is a slightly complicated procedure requiring a stable and precise 3V source.
 
Status
Not open for further replies.