I have two amps (ignoring the brands to avoid bias, but they are both known and credible brands) , 5 watts, with push-pull 12bh7 cathode biased power amps.
Actually one is marketed as a class A amp, the other doesn't say. Yet the latter is louder. Not incredibly more loud, but quite noticeably so. As I bought the class A amp B stock, I am getting paranoid that the output transformer is damaged. I have run into that problem before many years ago. The amp sounded fine, but power was very low. Replaced the output transformer (I don't even know how I managed, as my electronics knowledge is extremely low, I am just a musician) and the amp came back to life (loudness wise).
So what I am asking is, is it possible that the 'class A amp' doesn't sound as loud simply because it's a different design? Thanks.
Actually one is marketed as a class A amp, the other doesn't say. Yet the latter is louder. Not incredibly more loud, but quite noticeably so. As I bought the class A amp B stock, I am getting paranoid that the output transformer is damaged. I have run into that problem before many years ago. The amp sounded fine, but power was very low. Replaced the output transformer (I don't even know how I managed, as my electronics knowledge is extremely low, I am just a musician) and the amp came back to life (loudness wise).
So what I am asking is, is it possible that the 'class A amp' doesn't sound as loud simply because it's a different design? Thanks.
The fact that they use the same tube doesn't mean they are equally loud.
There's lots of variables that can cause different loudness with the same speaker and the same volume control setting.
B+ for instance, the bias point, the gain, the output xformer, etc.
It would be quite a coincidence if they were equally loud!
Jan
There's lots of variables that can cause different loudness with the same speaker and the same volume control setting.
B+ for instance, the bias point, the gain, the output xformer, etc.
It would be quite a coincidence if they were equally loud!
Jan
Thank you!
''It would be quite a coincidence if they were equally loud!''. Wow, no less. I had no idea, thank you so much. 🙂
''It would be quite a coincidence if they were equally loud!''. Wow, no less. I had no idea, thank you so much. 🙂
Try to see if you can get them equally loud with different volume settings.
Do they have an onboard volume control or are you using a preamp?
If they have their own volume control you can set them for equal loudness.
And I assume you compared them on the same speakers, if not there's another variable as speakers can have large differences in efficiency.
Jan
Do they have an onboard volume control or are you using a preamp?
If they have their own volume control you can set them for equal loudness.
And I assume you compared them on the same speakers, if not there's another variable as speakers can have large differences in efficiency.
Jan
oh yeah, same speaker, same volume settings (maxed out AND boosted the same). The louder amp has more power amp distortion, the other is cleaner. Interestingly, I just compared the quieter tube amp with a 5 watts rms solid state amp (always with same speaker) and guess what, their loudness is similar. Not exactly the same, but at least I know the quieter tube amp was not damaged. My fear was that someone had turned it on without the speaker attached (all the amps are guitar amp heads and come with no speaker) and damaged the output. But now I know that's extremely unlikely, and the quieter amp is an ex demo coming straight from a guitar shop. So it's super unlikely that the output is damaged, in this case sometimes it sounds fine, but most of the times the distortion is ugly, which isn't the case with any of the amps. Thank you 🙂
Last edited:
If you ran a guitar amp with no speaker and it still works afterwards you didn’t damage the output trafo. If you blew it or shorted between turns you would really NOTICE a drop in output, or stopping functioning altogether.
You might actually see fireworks if you do damage something.
You might actually see fireworks if you do damage something.
Thank you.
'' If you blew it or shorted between turns you would really NOTICE a drop in output, or stopping functioning altogether.''
I see. In fact, the ones I played that were damaged for sure, had VERY low power, for example what seemed a couple of watts instead of 50, or they were totally silent. Thanks 🙂
'' If you blew it or shorted between turns you would really NOTICE a drop in output, or stopping functioning altogether.''
I see. In fact, the ones I played that were damaged for sure, had VERY low power, for example what seemed a couple of watts instead of 50, or they were totally silent. Thanks 🙂
Loudness is subjective (unless a test tone measured by an SPL meter). More distortion subjectively sounds louder than less distortion.
