Hi everyone,
Does anyone have built this amp so far?
It looks good to me. I want to either build this or LYNX-3.
Which one do you suggest?
Would someone please clarify me why powerAms having an opamp in their first stage aren't so popular?(like PA-300 from Elektor)
Regards!
Ermac
it looks to me that someone has redrawn this with a 4pair output stage. They have increased the supply voltage without regard to what voltage suits the transistors specified.
It uses driver devices for the pr-driver and Vbe multiplier.
And uses driver devices for the VAS.
These devices should be low Cob, high gain (at low current), High fT at low current, high Vce0
Most of the voltage amp stage uses 546/556 these are 65V devices.
Do you really expect all of them to survive 140V? (i.e. Vc + |Ve| = 70+70 = 140)
It uses driver devices for the pr-driver and Vbe multiplier.
And uses driver devices for the VAS.
These devices should be low Cob, high gain (at low current), High fT at low current, high Vce0
Most of the voltage amp stage uses 546/556 these are 65V devices.
Do you really expect all of them to survive 140V? (i.e. Vc + |Ve| = 70+70 = 140)
AndrewT said:yes. 4pair of mJ14003/4 kept cool can drive a 2ohm speaker load from +-50Vdc.
If sufficient smoothing is fitted and a high dissipation heatsink is used, you may get 400W into 2ohms
Exactly, I want to do so! But I hesitate whether build LYNX3.0 or Melody. LYNX with opamp in its fisrt stage and Melody with transistors... Which one do you suggest?
well I have just plugged in the data for my excel model as suggested.
I have an answer to
I have an answer to
Don't be silly!+/- 70V Rail Can Drive 2ohms
EMX_125 said:Hi.. Sir Andrew
If +/- 70V Rail i guess 4ohms is Fine...
Yes, it is. BTW if you built it, post the pcb layout here.
Yes, it is. BTW if you built it, post the pcb layout here.
I have not the PCB layout this amp so if you have maybe your post here....
EMX_125 said:Hi.. Sir Andrew
If +/- 70V Rail i guess 4ohms is Fine...
NO!!!
See post #3!
EMX_125 said:6pairs of output transistors can be +/-70V rail voltage.
See AndrewT's post about the low Vce0 of LTP and driver transistors!
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