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I noted quite a bit more bass when I swapped the MoFo amp in after listing to other amps like ACA, Aleph-X, and M2. A few years ago, I brought my MoFo amp to another member's house for an audio meet and this was the quick consensus there as well.
Hi Eric, did you notice any fuzziness or buzz in the high end with the MoFo? I'd generalize this question to any common drain choke loaded amp actually.
Wish I had the gear and nous to send a square wave through these chokes to see if and what frequency they start to ring at.
Buzz in the high end is not normal for any amp.
Looking at the picture that you posted, it looks like your amp has the choke and amplfier circuit loosely placed on the bottom shelf of a rack, with loose RCA connectors, and no sign of the power supply. This wide spread layout may be making your amplifier susceptible to picking up interference.
What is providing DC power to your MoFo? Power supply noise?
There could be other reasons for the buzz. Perhaps oscillation? Preamp or source noise because a much higher signal voltage is required for the MoFo?
Looking at the picture that you posted, it looks like your amp has the choke and amplfier circuit loosely placed on the bottom shelf of a rack, with loose RCA connectors, and no sign of the power supply. This wide spread layout may be making your amplifier susceptible to picking up interference.
What is providing DC power to your MoFo? Power supply noise?
There could be other reasons for the buzz. Perhaps oscillation? Preamp or source noise because a much higher signal voltage is required for the MoFo?
Ranshdow, I'm using the same choke and have a similar layout to yours(except attached to a chassis). I've run mine without the cover and never had any buzzing. I noticed two things in your pic. Interesting heat sink clips 
. And the RCA connectors at the Mofo input look awfully close to the heat sinks. Are they touching it?
. And the RCA connectors at the Mofo input look awfully close to the heat sinks. Are they touching it?
The 'buzzing' I describe is subtle. If you're familiar with the vocals on say the first two Crosby, Stills and Nash (and Young) albums, it's probably a characteristic of the microphones and vinyl recordings used on those albums. To me in this system it sounds exaggerated with the setup shown. For what it's worth, when I crank the volume on the preamp all the way up on the system as shown, I hear less line noise than I did with the ACA (SMPS supply) or with a borrowed Aleph J or with my old Rega BRIO, both with linear power supplies. The MoFos with the 19V laptop bricks are actually quite quiet to line noise, despite all the hack cable overlaps you can see.
Ranshdow, I'm using the same choke and have a similar layout to yours(except attached to a chassis). I've run mine without the cover and never had any buzzing. I noticed two things in your pic. Interesting heat sink clips
Lol I got frustrated looking for aluminum metal work, and yea the ignition wrenches seem to work.. can't decide if I should be embarrassed or proud! ;D
Is now few hours I play music through MOFO amp with a high gain triode preamp and class A audio source.
Thanks Michael is BAF projects who make me happy
What is that device in the right top corner just below the soldering iron?
can't find out. Taking the dust off the MOFO?
Static collector.
It is better to put a pot of water to be boiled down there.
Because to shave off the harmonics, the current MUST go up.
ZM suggested upwards at least of 1.8 amps for drain loaded (nonmofo). Higher better. Should be same for source loaded. 3.5 amps?
Mwah. is nothing.
Then you can start cooking.
Because to shave off the harmonics, the current MUST go up.
ZM suggested upwards at least of 1.8 amps for drain loaded (nonmofo). Higher better. Should be same for source loaded. 3.5 amps?
Mwah. is nothing.
Then you can start cooking.
removing unused MOT windings
I'll be receiving my microwave oven transformers today or tomorrow, and I was wondering about the pros and cons of removing the unused windings. Seems like doing so takes away any issues about possible interactions with the choke winding. What are the considerations?
I'll be receiving my microwave oven transformers today or tomorrow, and I was wondering about the pros and cons of removing the unused windings. Seems like doing so takes away any issues about possible interactions with the choke winding. What are the considerations?
I cobbled together a hockey puck MOFO (IXFN140N20P). Really just dropped the puck in the circuit with no changes other than a bigger choke, added a 0.01R resistor in series with V+ as a convenient way to measure bias, but thats about it. I'd like to 'upgrade' the input/output caps. Is there an optimal/appropriate size for these caps, based on device/bias/rail voltage? Using a J113 buffer in front. Currently 35VDS @ 3A...sounds fantastic.
-john
-john
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I didn't mean esoteric. I usually pick whats most available on Mouser, no brand preference. Mainly concerned with the uF. I've seen input caps from 1uF to 10uF, and on the output 2200uF-10000uF, sometimes with a film and not. I know it has to do with obtaining a certain frequency response, but with a bigger device, does it really matter?