the power output is 150/200w max.
I am interessed an a hi-end sound quality, not a big power.
I use the totem pole tube 6sn7 preamplifier, i hope in big combination tube (old system) + class D (new system amplification).
Measured the L20D board for temp while music was playing using a DVM with thermocouple. I'm using linear supply +-63VDC and 4ohm rated speakers (speakers' impedance actually dip to 4ohms only at 100-150hz, most of the time they're above 6ohms for other frequencies).
Heatsink - 45degC
1.1K resistors (one of them beside LED) - 80degC
2.2K resistor (beside D669) - 100degC
This is with the chassis cover removed, and readings may go up another 10degC with cover in place.
Are these resistor temps too high, should higher wattage ones be used instead?
Heatsink - 45degC
1.1K resistors (one of them beside LED) - 80degC
2.2K resistor (beside D669) - 100degC
This is with the chassis cover removed, and readings may go up another 10degC with cover in place.
Are these resistor temps too high, should higher wattage ones be used instead?
B: yes, I also found this phenomenon, in some time ago I this a few resistance are replaced by 2 W power.
In the IRAUDAMP7S IR noted in 2K2/1 W apparently is not so correct, because the resistance the power consumption of the above about 1.3 W.
If you are some time before buying it, I suggest that you put the two resistance to change is 2 K2/2 W.
If no hav, please contact suppliers, I can send you a few.
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My 2.2k resistor is beginning to discolor after 1 day. Will be asking Zoe Tsang for a 2 watter as E14 doesn't carry this part.
Try changing the input DC blocking cap as well. Since my present sources are AC coupled, I shorted the input cap just to hear the difference. Significant gains - signal is just so much cleaner and less colored. Ymmv as some prefer the color of caps, in which case roll out your fave caps
Try changing the input DC blocking cap as well. Since my present sources are AC coupled, I shorted the input cap just to hear the difference. Significant gains - signal is just so much cleaner and less colored. Ymmv as some prefer the color of caps, in which case roll out your fave caps
I'm sorry I'm not quite understand your meaning.
L20D input capacitance can't cancel, also do not have to change.
The capacitance of the quality is very good, even more than the IR company provide the IRAUDAMP7S above the capacitance
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ok, but I can change this caps with a non polarizzed caps? ( I have a 22uf petp caps)
Is the input 22uf capacitor for DC blocking only, or does it do more
If no input capacitor, IRS2092 will not work.
In fact the larger of the capacitor is more small capacitance distortion.
I am listening to the L20D now with the input caps shorted, and it's not only working but sounding mighty fine across the entire freq range, giving more extended and detailed top end.
The input cap forms a high pass filter with the input 3.3K and this imposes a low freq cutoff, but no cap means no cutoff, no?
What am I missing - why is the input cap mandatory if my source is AC coupled?
The input cap forms a high pass filter with the input 3.3K and this imposes a low freq cutoff, but no cap means no cutoff, no?
What am I missing - why is the input cap mandatory if my source is AC coupled?
I am listening to the L20D now with the input caps shorted, and it's not only working but sounding mighty fine across the entire freq range, giving more extended and detailed top end.
The input cap forms a high pass filter with the input 3.3K and this imposes a low freq cutoff, but no cap means no cutoff, no?
What am I missing - why is the input cap mandatory if my source is AC coupled?
Amazing.
If you can use if you are free to use.
But I am not very suggested that such, it gives some dangerous.