I can run a simulation to see.
My guess is that it will not be any big difference.
Result.
2SK170 = 0.00012% THD at 1 Watt into 8 Ohm
2SK170 = 0.00016% another model
LSK170A = 0.00016% THD
J113 = 0.00028% THD
In SPICE simulation using my SPICE models.
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How about K240 parts? That's dual K170, and may be easier to find.
I can confirm that. However, their curves/parameters are very variable, and I don't recommend using them blindly.
I concur that the LU/LD1014 parts have a spread for bias conditions. The stash that Mr. Pass sent to me for matching resulted in nearly 100% matched pairs. The individual matched pairs slowly meander from the lowest Vgs to the highest Vgs. It requires at least 100 pcs to get mostly closely matched pairs.
I have never encountered a K240 part in the wild.
I have never encountered a K240 part in the wild.
In my schematic the LU1014D is biased 1.39A.
That is when I use a 1.2 Ohm resistor as Source resistor.
As you say there can be a spred.
For other LU1014D devices there can be another resistor that is needed to get the desired 1.4A.
The target should be 1.4 Ampere
That is when I use a 1.2 Ohm resistor as Source resistor.
As you say there can be a spred.
For other LU1014D devices there can be another resistor that is needed to get the desired 1.4A.
The target should be 1.4 Ampere
That seems true.
We can go a bit while changing the source resistor.
But if no resistor fits, we have a problem.
Another option is to select the resistor that comes closest. And go for it.
It is no big deal if we get 1.2A or even 1.5 Ampere.
But if this is impossible we must take another road.
Maybe some clever mind can find a solution.
We can go a bit while changing the source resistor.
But if no resistor fits, we have a problem.
Another option is to select the resistor that comes closest. And go for it.
It is no big deal if we get 1.2A or even 1.5 Ampere.
But if this is impossible we must take another road.
Maybe some clever mind can find a solution.
Yes, I have seen the F3 schematic.
Even can be 2.7//2.7 plus the 3rd resistor.
Can be different values.
Even can be 2.7//2.7 plus the 3rd resistor.
Can be different values.
I remember you used ZVP3310 in input of a ZEN variation to achieve higher input impedance.
If I am not mistaken.
If I am not mistaken.
With such low bias currents, maybe you should have a look at SMD devices :
U3 2SJ168
U4+U5 2SK2145GR
U6 2SK2145BL in parallel
U72SK2145BL in parallel
2SJ168 spice model is available at Toshiba.
2SK2145 = 2SK209, model of which I posted in DIYA before.
Cheers,
Patrick
U3 2SJ168
U4+U5 2SK2145GR
U6 2SK2145BL in parallel
U72SK2145BL in parallel
2SJ168 spice model is available at Toshiba.
2SK2145 = 2SK209, model of which I posted in DIYA before.
Cheers,
Patrick
Would the modulated cascode with the LD1014 by @Ihquam work to make this a higher power amplifier?
https://www.diyaudio.com/community/threads/lu1014d-modulated-cascode.397230/post-7301163
https://www.diyaudio.com/community/threads/lu1014d-modulated-cascode.397230/post-7301163
No, modulated cascode of LU1014D is for another type of use.
Besides, 6 Watt is enough. Ask Nelson Pass.
For example he has designed ACA Mini - with very little Watt.
Another thing is that +/-12 Supply can not be more than 6 Watt ....
Besides, 6 Watt is enough. Ask Nelson Pass.
For example he has designed ACA Mini - with very little Watt.
Another thing is that +/-12 Supply can not be more than 6 Watt ....
Hmm, what exactly do you mean by that? What would be the technical/conceptual reason why the modulated cascode would not work?
That may be true for some applications, but not for others. For example, if I want to listen loud with proper dynamics (no compression, no clipping) with a "normal" loudspeaker (say 8 Ohm, 92 dB/V/m), 6 Watt will not cut it.
What's wrong with ZV9 then ?
Or you just replace the LU1014 in post #16 with the ZV9 triode cell and then increase rail voltage.
Patrick
Or you just replace the LU1014 in post #16 with the ZV9 triode cell and then increase rail voltage.
Patrick
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