The LED can be powered by the SMPS if you want the normal "LED is on when amp is on" functionality. If you want the LED to be always on, the stand-by supply can supply the LED.
The Hypex soft start is intended for the older amp modules. It seems kind of silly to use it just for the power supply - a 6 V, 0.5W unregulated linear supply is much cheaper.
Colin mentioned that there was already a soft start mechanism on the Nord amp. Is this the same one as from the hypexshop link above? Or is this the extra soft start I should be layering onto the existing one? Thanks
We are talking about the SMPS1200A700 here. So you're saying to use the 15v aux supply that's powering buffer and amp modulator to power the 3.8v LED in the switch as well?
Where can you find the 6v 0.5w unregulated linear supply for cheaper?
Yes. Takes one resistor.
Build it. Takes a small transformer, rectifier bridge (or 4 1N4001 diodes) and a capacitor.
So you're going to put a resistor and a LED in the power feed for 1 of the channels critical buffer and modulator stages, and the other channel will get a feed direct without resistor and LED. Sounds like a bad idea.
Your time must be worth very little if you're going to try to save $40 (probably $20 after parts) and take all the time to do that. Then in the end have a poor solution anyways.
Last edited:
I haven't listened to them yet. The Hypex looks better built.
Data sheets:
https://www.hypex.nl/img/upload/doc/ncore_mp/nc502mp/Documentation/NC502MP_02xx_03xx.pdf
http://www.icepower.dk/files/solutions/icepower700as2_datasheet_1_0.pdf
You could probably tell us what sounds better from the data sheets alone 🙂
And why is that a bad idea? We are talking about a few tens of milliamps.
In what way is that solution "poor"?
As to time vs. cost, yes, if DIYers start valuing their time, there won't be much DIY left. If you are a manufacturer, and do a production run, doing a tiny print with 3 components is not much work, and is worthwhile if the end result is the same as using only a part of the functionality of a more expensive component. But of course every manufacturer (and every hobbyist) makes their own choices.
Yes, they do look pretty nice - had a chance to check them out (and have a chat with Jan-Peter of Hypex) at their stand at ISE2017 yesterday.
I won't be putting a resistor and LED in the path of the buffer and amp modulator of my amps. Especially 1 and not the other. But I suppose you can do what you want. We even use the Hypex softstart in our DAC because it's cheaper than I could build something with the same functionally for. And it's built already.
Had a chat with my local technician and he says the soft start requires a circuit board to be installed and there may not be space on the Nord amp for this. He will need to look to confirm. Any other way to do this soft start thing? Thanks.
The soft start PCB is pretty small. If you can't fit that in the box then you won't fit anything else either. Colin is already using the best high voltage push button switch with blue LED.
Damn. The thing is faulty. Demand an entirely new amp if Colin isn't prepared to fix it to flawless operation. You shouldn't have to fluff about with a commercial product.
I guess the issue is that he doesn't think there is anything wrong with it based on his measurements when it is powered on (I presume). I have emphasised to him that although the amp sounds normal once it is powered on, something must be causing the button to stick with increasing frequency.
I am half a world away in Asia, so whatever consumer protection laws you have in the UK won't apply to me and so making demands doesn't mean much unless he is convinced there is indeed something wrong. The amp has been with him more than a month so I hold little hope he can find the cause.
Listened to the flagship Icepower 700AS and didn't like it. Sounded colored and tonal balance was off. Nowhere near NC500 territory. Tried the Hypex MP502 and got rapid popping out of both speakers. Disconnected the inputs and same thing. Not sure what's up. Waiting to heard back from Hypex tech support. Already going on day 5 and no response from them. I guess they must be backlogged with emails or something.
Last edited:
The input impedance on this Icepower installment looks much better (36kohm) did I read that right?