I have 14,000. We could put them in the store....
Dear Mr. Pass,
Kindest regards,
M
please do. I am finishing my speakers that are on average about 94 dB/W efficient (the horns are more than that), so a small class A amplifier could be justified.
Kindest regards,
M
Can the LU1014 devices work in Mu mode? There seems to be a difference between SRPP vs. Mu-Follower. In this article and a few others I have read there seems to be some circuit changes that distinguish them and outlined here:
https://www.tubecad.com/2009/10/blog0173.htm
I need to ask this question because I have been simulating like crazy but only get "good" results with SRPP mode tho the article states Mu is better to drive low impedance loads but I don't have the aptitude to try and work out the maths for the resistors that are added in this configuration:
Also, I showed my circuit to a retired Bell Labs engineer friend who studied the datasheet charts for LU1014 and he also states that with proper heatsinking that the devices can run SRPP with up to 30vDC and it still allows for SOA with this voltage over 11W is seen on the sim at 8 ohm load.
The SRPP circuit is here:
https://www.tubecad.com/2009/10/blog0173.htm
I need to ask this question because I have been simulating like crazy but only get "good" results with SRPP mode tho the article states Mu is better to drive low impedance loads but I don't have the aptitude to try and work out the maths for the resistors that are added in this configuration:
Also, I showed my circuit to a retired Bell Labs engineer friend who studied the datasheet charts for LU1014 and he also states that with proper heatsinking that the devices can run SRPP with up to 30vDC and it still allows for SOA with this voltage over 11W is seen on the sim at 8 ohm load.
The SRPP circuit is here:
I am a noob, My understanding is that lu1014d's main problem is cannot swing enough voltage, Should use it under 5 volts Vds, power is limited by resistance of speaker. Maybe 2ohms speaker better? Is my understanding right?
The LU1014 is designed to be cascode. If you look at the safe operating area plot in the datasheet, where the LU can operate at the highest current, Vds is between 0.2v and 1.1v. Many present day high power devices are a JFET cascoded by a MOSFET.
Is it ideal to make a BTL of this circuit? Double the output Vp-p.
Lu1014d should be matched, but luckily I got hundreds of LD1014D.
Lu1014d should be matched, but luckily I got hundreds of LD1014D.
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Have a look at my post of curve tracer photo, If 25Vp-p output, does it mean to swing over 12V single element? It is NO GOOD from curve tracer test. Did you include the non-linear over 5 V for lu1014d in simulation?
I spent a lot of time trying to get LU1014D working in SRPP and no matter how I try they cannot go over 18V or so before breaking down so I switched to high current depletion mode Mosfets and will use the LU devices for only projects like Nelsons F3.
As Nelson said, you have to use the LU1014 in a triode cell with MOSFET cascode.
Here is one example without source resistor :
https://www.diyaudio.com/community/threads/the-lu1014-circlotron-power-buffer.399639/
Patrick
Here is one example without source resistor :
https://www.diyaudio.com/community/threads/the-lu1014-circlotron-power-buffer.399639/
Patrick
There are some gate leakage if you raise the Vds over 10 or so volts(I tested). Further more LU1014d just cannot maintain Vds over 10volts with any current. see pics.
I guess the possibility is the gate leak from lower lu1014d raised the gate voltage, conducting itself, and leave whole rail voltage to upper lu1014d, Then with several amps current your are leaving safe operation zone very very far. PS: just a noob guess. My suggestion is never oprate LU1014D over 5 volts. There is a good reason in the official document the curve is maxed at 5 volts (It's ugly over 5 volts) .
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I like the Idea, but not a 6W amp, this should be good to only 1-watt into 8ohm. because lu1014D will not be linear over 5 volts. Am I right? Might be a transistor version of 300B 😛
I tested what 8Vpp loudness sounds like. Turns out my normal listening level is only about 4Vpp at 6ohms🤔. Maybe I should seriously consider building one.
People who put a scope on amplifier outputs are usually surprised at how little power they are listening to.
