This is not an input selector. This is an input configuration selector. The switch only configures the internal circuitry for balanced or unbalanced operation, leaving both XLR and RCA plugs connected to the amp input. So if you leave both plugs connected, your sources definitely influence each other in a bad way - you have them paralleled directly.
So, yes - only one of them should be connected. Either, or...
So, yes - only one of them should be connected. Either, or...
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Assuming I keep the amp away from the carpet and the cat, what are the downsides to pushing up the bias on my 1 1/2 year old A21?
I have had a look at the bias on my recently acquired A21 after noticing just how much cooler it runs than my HCA2200ii. I was surprised to find that the bias setting voltage (across the emitter resistor) was very similar to the 2200, I measured 18mv one side and 22mv the other. I then, as carefully as possible, adjusted the pot to give 24mv each side. I was surprised to find that this made very little difference to the heat sink temperature, I was rather hoping for a bit more. I am now reticent to increase this again incase there is something I do not understand with the biasing method, however I am interested to do so because there are aspects of the 2200 performance which I feel the A21 does not match. (I was working on bias setting advice that was applicable to the 2200, assuming it would be a similar scheme to the A21). Could anyone say what setting to go for to put the A21 into a safe high bias mode? John suggesting increasing the bias until the amp is approaching its thermal protection limit, has anyone tried this and establish a figure?
Parasound A21 owner here and I really like it.
I'm thinking of adjusting the pots to say heatsinks 40C on 23C ambient. What value should be the voltage on the output resistors so I do not go over the edge with it. Average x mv? I see there are some fellows with the same question so we'd appreciate some support here.
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Well, I took the hard approach with a wattmeter measuring wattage at the inlet, increased each channel by roughly 25W watching the wattmeter closely as I turned the pots.
Both heatsinks measure roughly 31C now (21C ambient) with a digital thermometer. So far so good. I won't go higher as the consumption is now 130W and I have bills to pay.
As for the difference is close to none. Piega P10 speakers here.
Both heatsinks measure roughly 31C now (21C ambient) with a digital thermometer. So far so good. I won't go higher as the consumption is now 130W and I have bills to pay.
As for the difference is close to none. Piega P10 speakers here.