Need yea or nea on input switch

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Nordic said:
I think thechnicaly speaking, make before brake is in fact the right option...

this is true for most audio switching or steeped switches for volume
make before break

Because if is a resistor that keeps down impedance on the other side of switch
this resistor can be important.

The lack of a bias resistor at input terminal, for example
can make amplifier go really crazy,
if so only for a short moment.

Can make blips sounds.
 
Ladder type attenuators need break before make (otherwise the resistors can be paralelled for a moment resulting in higher volume (blips) between steps.

Series type attenuators need make before break type switches, otherwise the resistance parallel to the input of the poweramp will be broken off between steps.

Input switches need break before make on the positive wire in order to keep the blips out. The bias resitor should be placed on the output of the switch (input of amp), which is allready the case in most amps...
 
ground shall not be switched, all grounds remain conected all the time....

If ground would be disconnected and only signal was to be connected ENORMOUS hum would appear!:bigeyes:

That's why neutrik developed that rca with springloaded ground contact, the ground is connected first and thus connections can be made when equipment is "on".....without the hum....
 
Nordic said:
Yep imagine switching between 2 sources with volumes at max (m-b-b), for a tiny while they will load your input with their power combined in parallel....

Yeah ...
hmmm

add one battery 1.5 volt
across 10 kohm resistor

now add another battery 1.5
across this 10 kohm resistor

now how much voltage you have across 10 kohm resistor
a little hint .... it might not be 3 volt


So when thinking a bit more
I still say, with a few exceptions ( exceptions are not the rule ):
Generally - Make before break switches
are more useful in audio




Of course when somebody ask a general question, exceptions will be included in some answers.
A rule from which there are NO EXCEPTIONS:
Be specific, if you want a reply that is relevant to your situation.

Now that we know it is the input to a Peter Daniel chip amp kit
we could give a 100% valid answer :)


At least maybe,
if we are clever enough to remember difference between parallel and serial
connection of 2 batteries ...... 2 voltage sources


Regards
lineup
 
Ok. So which type is used in the industry? Which type have you all used in the past?

I think I could probably go either way. But if any of you have used one type or the other, or both, inform me of the performance.

I thought this would be a simple question but, is turning into an interesting discussion. ;)
 
I've recently pulled apart an older yamaha pre-amp with some nice switches in it, they're break before make.....

The most common thing that happens with a make before break is a little "click"sound you hear through the speaker. I've never wrecked anything by parallelling outputs, but some preamps/output sections have less than 100 ohms output impedance. So not only the 10k input impedance of the amp should be calculated with, the output sections -depending on the output/protection/circuitry and the resulting impedance- might not like this.:hot:

A battery is dc, parallelling dc will result in no current flowing:whazzat:, parallelling wave-shaped signals can result in a sort of periodic short circuitry (current flowing) and as some outputs even generate peaks of 6 volts parts could get toasted!

I would stay with a break before make :yes:
 
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