It measures like it sounds, lack of detail and dynamics. It sounds like an amplifier from the 70s, good in its day, but things have moved on. The L12/2 is so much better in EVERY way. Square waves are really square. Frequency response is ruler flat. Slew rate on the Quad is really poor, and you can hear it. The crossover artifacts were probably due to your low operating voltage. A duel 50 volts works better. Note clipping is not symmetrical, at any voltage. Valve lovers will love it, has the same type of sound. (if you know what I mean!!)
Cheers for your input Michael, much appreciated. I'm in 100% agreement the L2-2 is a better amplifier circuit for us YTbers looking for a nice kit to build, and maybe use for listening pleasure.
If the amp is a 1 to 1 copy of the Quad 405 then they have the same issues regarding blowing up the driver transistors. The outout of the op-amp has a series capacitorr, a teardrop tantalium capacitor 100uF 3V !! If the tantalium goes bad the whole driver section will be distroyed. Replace the tantalium with a 25V (or higher voltage) one to prevent this issue.
@@Elecifun Yes it does, it's the little green drop-capacitor right in front of the opamp IC. The 405 tends to oscilate sometimes! That wil damage the little tantalium . I have repaired hundreds of 405's past 4 decades ;-)
@@nicoleeman2257 as I have it in front of me, I can assure you it is tantalum free. In front of the opamp is a film cap. Thanks for the heads up thought.
Cool. Since this is a "QUAD" based amplifier, I guess the final transistors are both NPN in push-pull configuration? In my opinion this dual NPN output is better than the usual NPN/PNP push-pull config. The reason why is that NPN and PNP transistors are made differently, and are not symmetric with respect to the active layers inside.
LOL. I just finished cleaning up my bench from the OX7 build. It looked like a demilitarized zone.😂 Today will be software configuration and if all goes well, the maiden flight!
It measures like it sounds, lack of detail and dynamics. It sounds like an amplifier from the 70s, good in its day, but things have moved on. The L12/2 is so much better in EVERY way. Square waves are really square. Frequency response is ruler flat. Slew rate on the Quad is really poor, and you can hear it.
The crossover artifacts were probably due to your low operating voltage. A duel 50 volts works better. Note clipping is not symmetrical, at any voltage.
Valve lovers will love it, has the same type of sound. (if you know what I mean!!)
Cheers for your input Michael, much appreciated.
I'm in 100% agreement the L2-2 is a better amplifier circuit for us YTbers looking for a nice kit to build, and maybe use for listening pleasure.
Tidy kit Elecifun. Looks like a nice amplifier. Thank you for posting that amigo. 🍻
Thanks for watching!
If the amp is a 1 to 1 copy of the Quad 405 then they have the same issues regarding blowing up the driver transistors.
The outout of the op-amp has a series capacitorr, a teardrop tantalium capacitor 100uF 3V !!
If the tantalium goes bad the whole driver section will be distroyed.
Replace the tantalium with a 25V (or higher voltage) one to prevent this issue.
It doesn't have a tantalum capacitor.
@@Elecifun Yes it does, it's the little green drop-capacitor right in front of the opamp IC. The 405 tends to oscilate sometimes! That wil damage the little tantalium . I have repaired hundreds of 405's past 4 decades ;-)
@@nicoleeman2257 as I have it in front of me, I can assure you it is tantalum free. In front of the opamp is a film cap.
Thanks for the heads up thought.
Cool. Since this is a "QUAD" based amplifier, I guess the final transistors are both NPN in push-pull configuration? In my opinion this dual NPN output is better than the usual NPN/PNP push-pull config. The reason why is that NPN and PNP transistors are made differently, and are not symmetric with respect to the active layers inside.
@la7yka You are correct two NPN's in push pull configuration. Thanks for your input friend.
It's got a 6 Watt class A circuit as well.... that's why the heat up even when not in use ;-)
LOL. I just finished cleaning up my bench from the OX7 build. It looked like a demilitarized zone.😂 Today will be software configuration and if all goes well, the maiden flight!
Oh wow! cant wait to see that. I wait with bated breath. Happy maiden amigo!
Thanks amigo!
Is this a new amp sir? You've built so many im losing track. 🤔
Hi Dec, Its a newer version (V3) of the Quad405 amp which I built and tested a little while ago.
@@Elecifun Oh IC. 😄👍
@@Elecifun What's the difference? 🤔
@@Elecifun What happened to the L12-2?
I use the L12-2 here at home. Its a good amplifier and will be tough to beat, picking circuits from Aliexpress.