thats the point of vr1 it sets the bias and the voltage before the cap to 1.5 let me send the .asc file
They seem to small for a 2A at 15V . Maybe a fan on them will do. Adjust R4 R2 for 1/2 V and maybe a Iq of 500mA - 1A .
according to ltspice they only need to dissipate 13W per heatsink, with a good thermal coupling it will be fine, also my power output would be close to 1w if i did it
Your amp will dissipate the full power all the time, regardless of the output . It's class A .
i know, but i do believe that my heatsinks are competent enough, if theyre not i can just add an fan
here is the heatsink, im gonna use one per transistor and i wont bother with myca sheets becuse well its one per transistor.
it seems that i can push it quite far at 4 ohms, i also observed that at diffrent loads the gain changes quite a lot.
i know although im intrested in what chassy i should put the amp in and where in the circuit to wire an volume control potentiometer
i almost finished building the thing. now i need to power it up and test how it sounds. also im once again asking where to put the volume control potentiometer to not limit the frequency response?
At the input of the circuit, if you use a 10k pot.
But a low impedance buffer stage after the pot will be a good idea.
The bias adjustment may cause an imbalance between channels in the pot
without a low impedance source.
But a low impedance buffer stage after the pot will be a good idea.
The bias adjustment may cause an imbalance between channels in the pot
without a low impedance source.
from this first prototype i know that heat is an isse and the biasing can get very off becuse of it id also need an bigger source resistor for the current source to run it at even one volt more, it works but id need to invest in a bigger heatsink, significantly bigger.
These heatsinks will proably sink max. 3 watt heat)-;
For the desired power (15V, 1 A ?) I recommend TO-220 transistors. They run without any problems at this power and sound much better (higher resolution, better interplay of frequencies as sound, cleaner...) than the TO-247 MosFets. MosFets should not be allowed to run too hot in the long term, as they become sonically rotten. I currently have an SE: TO-220 at 34V, 2 A running, but BJTs, to my ears they also sound much more elaborated, more physical, more organized.... than comparable MosFets.
For the desired power (15V, 1 A ?) I recommend TO-220 transistors. They run without any problems at this power and sound much better (higher resolution, better interplay of frequencies as sound, cleaner...) than the TO-247 MosFets. MosFets should not be allowed to run too hot in the long term, as they become sonically rotten. I currently have an SE: TO-220 at 34V, 2 A running, but BJTs, to my ears they also sound much more elaborated, more physical, more organized.... than comparable MosFets.
its more of an i already have these issue, but i also have a set of 2n3055 (NOS found a bag full at school) and an way too big heatsink with all the mounting aparatus
if i were to use bjt's id need a gain stage such as this one or an single transistor and an transformer
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Yes, there already is an input capacitor in the diagram, since there is a DC voltage present at the input.
If the bias pots were at about the same setting, you could use a 10k stereo linear pot
and let the input impedance convert it to quasi-log. But if the pots are set very differently,
there will be a channel imbalance due to that difference, so a buffer may be needed with an input pot.