I love this kid, he is a genius and doesn't even know it. He simply let Nelson talk, with open ended questions that allowed Nelson to express so much.
If no one got what Nelson is onto with his simple designs, this video explains it better than ANY I have ever seen. Also someone really needs to interview Jill.
If no one got what Nelson is onto with his simple designs, this video explains it better than ANY I have ever seen. Also someone really needs to interview Jill.
there is a rumor about Papa''s regular Podcast
ZM is just causing trouble. However, Mike Rothacher and I have plans to do some project videos soon.
One thing that is not often mentioned when talking about low power amps is the output impedance of the amp. I think this has some influence of how the deep end is presented. Even if the impedance never dips below 4 ohm and max. power stays below 5W. That is my experience driving my OB's which has a 15" at the low end (< 170 Hz). I am playing with my VFET (no. 33) and after a while I tried using a class-D for the 15". This turned out to get me much more "punch" and to my ear the mid/high got more dynamic. With this setup I have a sense of "unlimited" dynamics and great 3D/depth in the music.
A test track I use to check the "punch" and low end control is Steve Smith: Drums stop, no good played at a bit loud level. It was easy to hear that with class-D driving the 15" the bass control was better and VFET sounded more "relaxed".
Next is which sound you best like.........
A test track I use to check the "punch" and low end control is Steve Smith: Drums stop, no good played at a bit loud level. It was easy to hear that with class-D driving the 15" the bass control was better and VFET sounded more "relaxed".
Next is which sound you best like.........
I have been using classA amps, Mr. Nelson's designs mostly, only from 150Hz up, with efficient 8 ohm mid/tweeters, for decades. Plate amp for woofers on open baffle. Active biamp. Plenty of flexibility.
This allows low power classA amps to shine.
Side note: I noticed, that even amp alone measures flat, and speakers alone measure reasonably flat, swapping various classA amps results in vastly different fr response in listening position. Try for yourself. This is mainly due to vastly different damping factors of various amps. Sound differences are therefore expected. Likely totally different for different speakers with vastly different impedance curves.
I always eq flat in the listening position. This normalizes things a lot when comparing sound of various amps, preamps or speakers.
Till we have all speakers with flat impedance, classA amps swapping, especially current source ones will yield vastly different response. Fact totally ignored by reviewers.
Cheers.
This allows low power classA amps to shine.
Side note: I noticed, that even amp alone measures flat, and speakers alone measure reasonably flat, swapping various classA amps results in vastly different fr response in listening position. Try for yourself. This is mainly due to vastly different damping factors of various amps. Sound differences are therefore expected. Likely totally different for different speakers with vastly different impedance curves.
I always eq flat in the listening position. This normalizes things a lot when comparing sound of various amps, preamps or speakers.
Till we have all speakers with flat impedance, classA amps swapping, especially current source ones will yield vastly different response. Fact totally ignored by reviewers.
Cheers.
Think the Class-D amp I use for the 15" woofers has a specified damping factor >1000.
I noticed that VFET amp changed sound when it only had to drive the mid/tweeter. The distortion profile will also change (less distortion I assume).
There are many many combinations to try out. I need to listen to at setup for some time to be able to find out if I like it or not. I need to compensate for the "psychological factor" when I do a change. Often it should very good just after the change but then after some time listening.......it was not that good......
For the moment I have not been active in building as I am quite satisfied with current setup. There has also been a lot of experiments with listening position, damping of room etc.
I noticed that VFET amp changed sound when it only had to drive the mid/tweeter. The distortion profile will also change (less distortion I assume).
There are many many combinations to try out. I need to listen to at setup for some time to be able to find out if I like it or not. I need to compensate for the "psychological factor" when I do a change. Often it should very good just after the change but then after some time listening.......it was not that good......
For the moment I have not been active in building as I am quite satisfied with current setup. There has also been a lot of experiments with listening position, damping of room etc.