2. amps-preamps
  3. 140029-80294

Does anyone care to ask an amplifier designer a technical question? My door is open.

I closed the cable and fuse thread because the trolls were making a mess of things. I hope they dont find me here.

I design Tube and Solid State power amps and preamps for Music Reference. I have a degree in Electrical Engineering, have trained my ears keenly to hear frequency response differences, distortion and pretty good at guessing SPL. Ive spent 40 years doing that as a tech, store owner, and designer.
.
Perhaps someone would like to ask a question about how one designs a successfull amplifier? What determines damping factor and what damping factor does besides damping the woofer. There is an entirely different, I feel better way to look at damping and call it Regulation , which is 1/damping.

I like to tell true stories of my experience with others in this industry.

I have started a school which you can visit at http://berkeleyhifischool.com/ There you can see some of my presentations.

On YouTube go to the Music Reference channel to see how to design and build your own tube linestage. The series has over 200,000 views. You have to hit the video tab to see all.

I am not here to advertise for MR. Soon I will be making and posting more videos on YouTube. I don’t make any money off the videos, I just want to share knowledge and I hope others will share knowledge. Asking a good question is actually a display of your knowledge because you know enough to formulate a decent question.

Starting in January I plan to make these videos and post them on the HiFi school site and hosted on a new YouTube channel belonging to the school.


128x128ramtubes
ramtubes's avatar
ramtubes OP
460 posts
 
@c1ferrari    Re: Beveridge
Hi, Roger,
You'd worked on the Bev DD amps for my Model II's when you were situated in Santa Barbara. Unfortunately, Rick was unable to complete the restoration process and my panels require attention. Can you assist?
Thanks for the attention.


We havent done any panels for a long time. Chat with the other fellow on here who wants to stretch some mylar. We have the right Mylar as mentioned in my reply.
ramtubes's avatar
ramtubes OP
460 posts
 
@jyprez 

yes, I would be happy to pay for coursework on the subject. What do you offer?

Currrently basic amplifier design. Are you local to Richmond. CA 94806?
ramtubes's avatar
ramtubes OP
460 posts
 
ON TONE CONTROLS

The typical bass control has a hinge point at 1,000 cycles, much too high. In my system I use the Subwoofer level control (100 Hz and below) to set the bass to the right level without making vocals muddy like most tone controls do. Typical bass controls have lift the male vocal 3 dB to get 6 dB in the low bass. We dont want to hear that. 

My woofer level control is right next to my volume control on my crossover and I note I move it several dB depending on the recording, listening level and bass quality.

For treble, usually I want a cut for bright recordings, rarely would I want a boost. A cut control is much easier to make than a boost. Typical cut/boost controls have a hinge at 1,000 also which is too low.

Whoever chose 1 KHZ as the hinge point made a big mistake, and once  made was copied over and over. I would choose around 200 Hz for the bass and 4 Khz for the treble and leave 200-4,000 unmodified.
4krow
80 posts
 
Concerning tone controls, thank you,,, very good to know.
ramtubes's avatar
ramtubes OP
460 posts
 
Concerning tone controls, thank you,,, very good to know


It appears in design the good ideas are only done briefly by the few yet the bad ideas are done by the many and go on forever.

I think the choice of a single hinge point was the biggest mistake. Its actually easier to split them in two which I did in the C-4 preamp.
More to discover