Got both my amps setup and playing back some music right now.
Only question I have, is it safe to playback with whatever DC was on the outputs? What about shutting the amps down? Are either the above going to hurt my speakers?
Only question I have, is it safe to playback with whatever DC was on the outputs? What about shutting the amps down? Are either the above going to hurt my speakers?
I have played with 800 mv for a while. Depends on you speakers ! Electrostatic speakers is nono.
Just measured 300 mv at the input without a source. So should I try 2x 47 kohm from each phase to gnd ?
Hot/ground and 47 kohm did not bring me any sound before turnoff. This was with my Erno pre wich is SE out.
0.5 V into 4 ohms is 0.06W (and it is only going to the woofer, as the crossover will cut off DC from the mid and tweeter). It won't burn your speaker. It might cause a slight increase in distortion due to the biasing of the speaker.
You didn't manage to get the SMPS Standby input to work?
Haven't done the standby yet, was looking for an alternative to putting a 9V battery inside the chassis. Was hoping the necessary 3-12VDC was available somewhere inside.
OK, was just curious to hear if you got it to work. I probably won't have access to my workshop until next week, otherwise I would measure to see if there still is voltage on one or more of the SMPS outputs even when in standby, but I am pretty sure the SMPS shuts off almost completely. On the other hand, you should also be OK leaving the SMPS on all the time (the idle power is quite low) and switching the amp on/off with the nAMPON input on the amp.
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Ya, I may just switch the nAMPon for simplicity.
I really want to get rid of this DC though and still haven't heard from hypex. If I buy a couple 47k ohm resistors is there a certain wattage I need? 1/2W ok or do I need a 1W, or even greater?
I really want to get rid of this DC though and still haven't heard from hypex. If I buy a couple 47k ohm resistors is there a certain wattage I need? 1/2W ok or do I need a 1W, or even greater?
Even 1/4 watt is fine - get 1% or 2% ones, not the 10% or 20% "standard" stuff.
Got an anwer from Hypex now. They asked me the same question. I will try with an variotrafo if a smaller voltage is ok. They can work down to 35 V.
I do not know if I have made a fault some where during mounting. If gnd on the supply for the input section is missing would that destroy anything ?
I wonder how much ripple there is on your supply voltage - the ripple peaks might possibly go high enough to trigger the overvoltage protection.
Maybe because there is some hum. I use unscreened cables. Maybe I shall use one of the 4 gnd for opamp gnd instead of coupling the gnd from the small supply to end of gnd to output section.
When I turn up the voltage it stop playing around 64 V. I use only one bridge. Double bridge will bring down the ripple a bit and also the suplly 0,7 V. Could be enough.
No hum without input cable . My pre do not usally hum. Will buy double bridges for both supplys and couple the gnd as early as possible.
Hope somebody else will find my exsperience usefull.
Hope somebody else will find my exsperience usefull.
Using the Legato 3.1 full balanced. With aprox 40 V to buffer there is sound. No hum at all.
Turn up the voltage to over 63 V and sound dissapears. This MUST be a fault from Hypex and not mine.
I am angry I have spent all to much time on this. 😡😡😡
Turn up the voltage to over 63 V and sound dissapears. This MUST be a fault from Hypex and not mine.
I am angry I have spent all to much time on this. 😡😡😡
you are focusing on the main power supply, which I think is not your problem. You appear to be over-voltaging the driver or signal power supplies. This comes from your misunderstanding the data sheets. The amp is going into protection mode because you are doing the wrong things.
This is DIY, if you don't understand, don't do it, buy the provided power supply unit which works without the user needing to know anything or teach yourself the things you need to know BEFORE you build it.
Be angry with yourself.
Alan
I ended up finding some 1/2watt 47k resistors locally. They have a red tolerance band so 2%? (yellow, violet, orange, red).
I bought 4 of them, now where exactly do I install them? Do I need one or two for each amp?
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