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
tomic601's avatar
tomic601
12,956 posts
 
as for factorials for decimals, try the gamma function

the gamma ray is also effective for trolls who add ZERO
bdp24's avatar
bdp24
9,866 posts
 
@tomic601, Oops, I had you confused with clio09! He DOES have a professional relationship with Roger. I’ll put the Decca info up in a thread, for all to see, hopefully tomorrow---Eric.
ct0517's avatar
ct0517
2,041 posts
 
Roger
this is related to a question you raised in past post on subs and remote controls.

ramtubes - The amp is any old SS 100+ watt amplifier. Currently a nothing special Denon. The woofer level control is on the crossover.

This solves a lot of problems with powered subs. Unless they have a remote (do they now?) it is difficult to adjust the level for different CDs,


Firstly I Agree, especially if someones subs are setup in typical fashion across the room with the main speakers.

My solution
I am using for the last two years, two Dynaudio BM12s studio subs in Room B with my Wayne Picquet restored Quad 57's. They (BM12s) are one example of a solution with a credit card sized remote control that handles db and crossover levels, phase, and allows you to save 4 settings. Classical is typically a higher DB setting then compressed popular music.
The BM12s are handling 60 hz and down and the RM10 has full control of the 57's. The subs come with their own Class A/B amps and on the boxes are heat sinks. Mine are now positioned on either side of the listening couch. This allows for the db levels to be set the lowest, phase 180. The sub amps heat sinks don't even get warm. Very little vibration from the boxes.

************

We last conversed about a year ago when I inquired about slope cards for an RM3 that I own. I was thinking about a project to bi-amp my Matrix 800's at the time.

btw - A nice surprise coming back here for winter conversations to find you have the most popular thread on Audiogon. 8^)

Cheers Chris

clio09
3,360 posts
 
@ct0517 - nice set up. I sometimes use my RM-10 with my ESL 57s in biamp set up. The Class AB amp I use for the bottom is a Luxman M-02. I use the Beveridge RM-3 (no remote) to crossover at 100 Hz, 4th order crossovers for both high and low pass. Rather than two woofers I use four in an asymmetrical array. I am curious how you settled on the 60 Hz cutoff and what other levels you may have experimented with.
wspohn's avatar
wspohn
608 posts
 
I have an amp maintenance question, if I may.

I favour amplifiers that are either Class A or at least have very rugged power supply capacity (I use several Classe DR3 VHC, a Belles A, a Rowland 5).  What are the symptoms of the supply caps being on the way out and at what general age do they become seriously at risk?  The Classe amps, for instance, are hitting 30 years old now.



Got into these way back to be able to drive 1 ohm speakers but stuck with them after speaker changes as I love the sound.
More to discover