This is not just another gainclone

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Peter Daniel said:
I do not expect any magnetic fields, but if they become problematic, I have some mu-metal sheets.;)

NOBODY expects magnetic fields! Their chief weapon is surprise... surprise and fear... fear and surprise... their two weapons are fear and surprise... and ruthless efficiency... their three weapons are fear, surprise, and ruthless efficiency... and an almost fanatical devotion to Faraday's Law... their four... no... amongst their weapons... amongst their weaponry... are such elements as fear, surprise...

se
 
A magnetic field depreciates inversely to the cube of the distance. ((I1/I2)=((D2/D1)^3).At the distances that i am guessing at(SWAG) it appears there would be little measurable influx of current into the wiring.
I built a mag levation device for my TT and at a distances of >1.7" could not measure any change in waveform or induced current during normal operation.
ron
 
ron clarke said:
A magnetic field depreciates inversely to the cube of the distance. ((I1/I2)=((D2/D1)^3).At the distances that i am guessing at(SWAG) it appears there would be little measurable influx of current into the wiring.
I built a mag levation device for my TT and at a distances of >1.7" could not measure any change in waveform or induced current during normal operation.

Not to mention that the magnets are working in opposition to each other so much of their radiated fields cancel.

se
 
Steve Eddy said:


Not to mention that the magnets are working in opposition to each other so much of their radiated fields cancel.

se

Are you sure the 2 fields automatically draw toward each other. Even if they do, I suspect that there is still some flux leaking backwards. I will check at work tomorrow as we are surrounded by many neodymium magnets there.

In the meantime, I know that placing the magnets in a pair of steel cups will direct the two fields away from the cups and towards each other.

:)ensen.
 
purplepeople said:
Are you sure the 2 fields automatically draw toward each other.

Not sure what you mean by "draw toward each other." Far as I'm aware, the resultant field should just be the sum of the two fields. The same principle is used with "shielded" loudspeaker drivers. They just take another magnet, flip it over and piggy-back it on the main magnet.

Even if they do, I suspect that there is still some flux leaking backwards.

Well, since they can't both occupy the same physical space, there will be some residual field.

In the meantime, I know that placing the magnets in a pair of steel cups will direct the two fields away from the cups and towards each other.

Yeah, those are called pot magnets. They usually have a ring of copper or brass around the magnet with the steel cup placed over that. Not sure exactly how that works but the result is that the field becomes more concentrated at the open end of the pot.

se
 
carlosfm said:
Why not shield the transformers with aluminium foil?:D :eek:

Heh! That's a good one. From what? Freezer burn?


Anyway, I did a quick experiment. A couple of magnets in a tube opposing each other. Makes a nice spring. There is definitely quite a bit of residual field as evidenced when my coins were picked up by the magnets.

So, I have to say that a bucking magnet doesn't necessarily create enough shielding for a monitor. It might be better to surround the driver with something low flux like magnetic vinyl.

:)ensen.
 
Scribble said:
Love how those LED illuminated knobs turned out


Yeah, like them myself as well. Í have both channels working now and I'm running the prototype around the clock in order to test this setup.

Maarten
 

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Very beatifull maarten, I've been visiting your site as well but'i'm still in the design phase of my gainclone.

Question: I would like to build a monoblock configuration, so with the transformer in the same box.

I know of the drawbacks but think they might be solvable if taken care of properly. The power section will be separated with a thick steel plate from the amp section and the volume switch will be at the back in the amp section wit an extended rod.

Additionally I've found these transformers. The are magnetically shielded and have additionally a shielding coil between the primary and secondary windings;

http://www.schuro.de/preisl-v-rkt-ms-sw.htm

has anybody experience with these type of shielded transformers in one box with the amp itself and with what results?
 
Re: Leds Bad New

analog_sa said:


Frank, i honestly don't see those leds going anywhere in a hurry. Besides they're blue which we didn't have in the seventies - their coolness factor more than makes up for the sound :)


colin.hepburn2 said:
Back in the late seventies we already knew that LEDs were bad news sonically
Hi
I agree it look good But Much rather Have audiophile sound than blue light But go for it if you wish


Just wait until your spouses see the purple LEDs... If it came to LEDs vs speaker placement, I'll sweeten my deal anytime with a little colour.

:)ensen.
 
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