All engineers are not qualified nor experienced in everything. Some are experienced in audio, some in control systems, some in avionic, some in missile control, some in radar, some in aerospace ..... Just because you are an engineer does not mean that you will or can design your own personal computer.
Agreed. I’m a CPA… people always ask me tax questions. I know next to nothing about taxes. And I now work in IT leading a development team. People always asked out PC troubleshooting or printer questions - which I’m near useless with.
This one is 50w into 4ohm but 0.02% distortion at 1khz. Full power bandwidth 350khz. Performance is down to the op amp that needs it's caps nearby.
Couldn't clean up the parts list
Design by a TI application engineer. 😉 Bugs me a bit so posted untested. Sign of the cross etc. Adjust to 50mv across VR1 which puts it into some class A but he doesn't say how much, just that it reduces distortion significantly. TR2 is epoxied to the heatsink. From memory as lots used the one he mentions is a thin TO92 type.
Star earth it all.
Couldn't clean up the parts list
Design by a TI application engineer. 😉 Bugs me a bit so posted untested. Sign of the cross etc. Adjust to 50mv across VR1 which puts it into some class A but he doesn't say how much, just that it reduces distortion significantly. TR2 is epoxied to the heatsink. From memory as lots used the one he mentions is a thin TO92 type.
Star earth it all.
Some of how amplifiers are usually measured does not completely predict the sound of an amplifier. That means one or more things that affect amplifier sound aren't typically being measured. IMHO and IME, all the more so for a stereo amplifier.
Amplifiers shouldn't have a sound(*). The signal determines the sound, that's the whole point!! And real examples of an amplifier design may not live up to their specifications due to aging, damage, component variation, so its wise to do some torture testing / re-checking of the specifications alongside any audition - the measuring equipment is usually hundreds of times more sensitive than the human ear, note.
That's why they typically don't sport cooling fans!
That's why they typically don't sport cooling fans!
Sure, but that's a philosophical statement. Not statement of what is or isn't typically being measured that can affect sound. Its also not a statement of whether or not typical specifications can fully define final sound.
Regarding claims about measurement equipment, a top of the line AP is good for some things and not so good for other things. What it does measure, doesn't mean that's all there is that could be measured.
What is stable? To an absolute layman, can you explain what you are looking for specifically in slew and clipping characteristics.
Which humans ear? Mine, yours, some other member on DIY audio? Are ears calibrated to some standard?
Using human ears as biological sensors may be considered as an objective form of measurement, if it is done properly. Otherwise things like thresholds of audibility would be considered subjective.
Moreover, Sean Olive (Toole's student and later collaborator) found that there there were advantages to using trained/expert listeners to evaluate speakers and headphones.
Moreover, Sean Olive (Toole's student and later collaborator) found that there there were advantages to using trained/expert listeners to evaluate speakers and headphones.
Distinguishes between hearing measurement methods and looking measurement methods. For audio (audire - to listen) I would prefer audiometry first, especially as looking-metrics are not calibrated to audiometry, are based on misunderstandings, such as failure to detect noise modulation: audible different characters of components.
... mostly still not detectable with loking measurement methods.
An easiest test for the different sensitivity and non-calibration of hearing and oscilloscope: connect your channel separated power supplies with each other. Listen and look;-) But I have made the experience that most of the supposed freaks and experts can't even follow the simplest methods, probably because their education didn't include method criticism and development;-)-;
... mostly still not detectable with loking measurement methods.
An easiest test for the different sensitivity and non-calibration of hearing and oscilloscope: connect your channel separated power supplies with each other. Listen and look;-) But I have made the experience that most of the supposed freaks and experts can't even follow the simplest methods, probably because their education didn't include method criticism and development;-)-;
;-)
A nice other example: I came across a batch of MosFets during component auditions that has a fine but clearly audible "echo";-)
A nice other example: I came across a batch of MosFets during component auditions that has a fine but clearly audible "echo";-)
You could take a look at Bonsai's
Hifisonix KX2-Amplifier thread
KX2 @ hifisonix
It's well documented, performs well and you can get pcb on ebay.
It can run in class A , AAB or AB.
If you only use class AB, you can use +-35V rails and it will provide 50W RMS into 8 Ω, and close to 100W into 4 Ω .
Hifisonix KX2-Amplifier thread
KX2 @ hifisonix
It's well documented, performs well and you can get pcb on ebay.
It can run in class A , AAB or AB.
If you only use class AB, you can use +-35V rails and it will provide 50W RMS into 8 Ω, and close to 100W into 4 Ω .
A/B doesn't exist. AB does, and has to be push-pull, but push-pull doesn't have to be AB.
It is also relevant whether the OP means AB as per Bob Cordell's (too wide) definition, or as per Doug Self's (and mine).
That still leaves what is classically referred to as class B, with 180 degree conduction angle, which Cordell calls AB, and real AB which is 180 < conduction angle < 360, which is rather a wide range. I don't deal with many if any AB's by this definition, and the exceptions are really Class A that verge into AB in extremis, but whether the OP means those , or overbiased class B, or real class B, remains an open question. To me.
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