MPP

[Joachim Gerhard]

We discussed that before. A big transformer does no harm besides the possibility to couple more HF, RF into the circuit then a smaller one. Others claim that big transformers have more slam and grunt.

 

[quan]

We discussed that before. A big transformer does no harm besides the possibility to couple more HF, RF into the circuit then a smaller one. Others claim that big transformers have more slam and grunt.

Ok thanks

 

[jacco vermeulen]

I will have to get rid of 30 Volts with an passive LCLCLC thing.

yikes.

 

[Joachim Gerhard]

Holger, something like this :AQvox-Tuning | Holger Barske

 

[Joachim Gerhard]

I have shown it several times but for the new comers here it is again:
I use the Preregulator from my Opus Magnum Phono Stage.
Because Block does not have 2 x 24V transformers i use 2 x 2 x 12V per side where i put the windings in series. The diode bridges are IXIS Silicon Carbide snubbert with REL teflon caps. The 10.000uF caps are slit foils, today i would use Mundorf 4 pole. The common mode chokes are from Lundahl. Loaded, the supply puts out plus-minus 30V, the maximum i recommend for the Paradise R3.

 

[RCruz]

Fantastic prereg... it must provide really good dc for the shunts.

Have you ever tried Jensen 4 poles ? IMO these permit great gains in trebble detail even when powering shunts.

 

[Joachim Gerhard]

No, i use Mundorf, mainly because i have a long busyness relationship to those guys and they are very helpful and friendly. I found the Mundorf 4 pole major in dynamics. I also use them in my power amp and the difference they made was huge. Especially in the bass.

 

[Joachim Gerhard]

Some time ago i posted some measurement i made on my prereg. The waveform before the common mode coils looked like a skewed triangle and after the coils it was much smoother. I really recommend a coil solution.

 

[Joachim Gerhard]

On the right side of the top Lundahl coil, in the cast cabinet you can see my low cost pre regulator. It uses Talema ferrite coils. The Lundahls are very expensive.

 

[RCruz]

They really look splendid these Lundahl... it is normal they have a high price tag

I will try to find those talema coils... what values do you recommend ?

 

[Joachim Gerhard]

I use this one :CAF 0,6-100 - Stromkompensierte Drossel, 100mH, 20 - 30mm bei reichelt elektronik

 

[Benedetto]

Another question from the fool;
should'nt we do some Pre-reg Boards for the poor in Wallet and mind ?

 

[Bksabath]

Another question from the fool;
should'nt we do some Pre-reg Boards for the poor in Wallet and mind ?

Splendid Idea sometink like those?

 

[Benedetto]

Eeeeexact !

 

[Bksabath]

Actualy you need 2 of those
I am making same new ones with some different cokes and extra one at output with 2 banks of capacitors.

Is not going to be this week as I got a 72 hour week so for now go back to FDW post.

I will post soon on the Paradise build tread

 

[Benedetto]

Thxalot !

 

[studiostevus]

I would probably build it P2P... no need for a pcb with such simple setup.

Joachim, why only a 100mH choke? I like these as an alternative to the prohibitively expensive Lundahls better.... Frag Jan zuerst- Ask Jan first: Roehren und mehr, the 10H 330R choke

 

[Benedetto]

hello Stev,
one one hand,
you're absolute right.
On the other,
does a perfboard match with those red cuties ?

 

[studiostevus]

Just a little sim.... with the Takema choke...



Actually better than I expected, even without any modelling of common-mode

 

[Joachim Gerhard]

Actually the original design had the Talemas BEFORE the diode bridges to get rid of the HF/RF noise from the transformer. They can be used though in a conventional CLC pi filter like you did simulate. A bigger inductance is even better, sure, but they are inexpensive so good for experimenting with this technology.