PLAN B analog blog

Also very interested in price / date for the psu and ringer...

A

On Fri, Jan 23, 2009 at 9:32 AM, Igor Medeiros <igormpc@gmail.com> wrote:
> this explanation about the way PSU & modules interact in these systems is
> very interesting, peter.
>
> can you tell us more about the external PSU you are releasing, and the
> price/dates we should expect for it & for the ringer?
>
> thx in advance
> igor
>
>
> On Fri, Jan 9, 2009 at 1:00 PM, (i think you can figure that out)
> <peter@buzzclick-music.com> wrote:
>>
>> There's a lot of words on this problem on this and other lists.
>>
>> It's ain't the M15's fault, partially an attribute of the
>> Frequenstiener's open loop transistor-based final amplifier stage and
>> largely due to the fact that Doepfer, Analogue Solutions and Analogue
>> Systems daisychain the ground connections on their busboards. Big no no.
>>
>> In fact you'd be able to hear LFOs out of the Frequen. if there was
>> one if those powered in the same rack. It could be Doepfer's, A.
>> Sys's, A. Sol's or mine. Put a Harvestman microp based module in the
>> same rack and your filter frequency will wiggle as if slightly
>> controlled by a squarewave LFO. Sounds like I'm bagging these guys,
>> I'm not - they're my friends. I'm making a comment about the
>> potential risks of daisychaining ground connections - those part of
>> the power distribution system AND those used on the circuits
>> themselves, in audio applications. You'll find on most Plan B
>> modules the grounds go on their own trace directly to the power
>> connector. These are the types of safeguards you must put in play to
>> keep things a quiet as possible. BUt this type of safegaurd goes out
>> the window on a power buss that ties it's grounds n a row instead of
>> individual feeds directly back to the PSU return.
>>
>> One thing you can do to kill the potential from the M15 contributing to
>> this keeping the square wave pot adjusted to the far left far right when
>> it's not being used, thus holding the square in it's DC range and not
>> generating a signal.
>>
>> While we're at it, an even more interesting attribute of the Steiner
>> circuit is if metal can 2N2222 transistors were used, putting your finger on
>> one or more of them while the unit is under power, depending on your
>> location you'll receive AM and Ham radio transmissions through the speakers.
>> Your location does not govern if it happens or not, your location
>> onlydetermines how busy the airwaves are, increasing the likelihood there's
>> a station at the filter's frequency band. basically there's an antenna in
>> play. I've pulled this anomaly from Cynthia, Ken Stone's and Elby's Stiener
>> filters - it's not them, it's the circuit.
>>
>> But in particular I need to stress this isn't Mike's issue. I was there
>> when he put this together, I got the Synthasystem schematic from Nyle for
>> him. Mike did an excellent job of reconstructing the original design and I
>> commend him for that. Not Mike's fault, it's the circuit but as a filter it
>> sounds marvelous, so (in a nice way), deal with it!
>>
>> Also remember that the original Steiner system was line level. Euro
>> is four times hotter. With that, the potentisal of this occurring is four
>> times as great. Such is the way things are in the 21th century when people
>> are pulling circuits from the old days and integrating them into
>> environments they weren't intended to be exposed to. Know though that I'm as
>> guilty as the rest of them with the M13.
>>
>> To chill this down a bit, try increasing the 10mf electrolytic caps
>> which filter the power inputs of the Frequenstiener. Then increase
>> any bypass caps used in the circuit. I'd be careful though - a cap is
>> littered with caps, some as bypass, and some part of the filtering
>> circuit. Basically the .01's should be increased to .1 but do a
>> listen test after each to make sre the particular cap isn't part of
>> the filter structure. Sorry, I can't publish the Stiener circuit, this
>> comes form a request of Nyle's. The Synthacon schematic is all over
>> the place, this one is very similar but has more diodes in the ladder.
>> Yu know what 90% of white noise circuits are based on? Diodes or
>> transistors configured as diodes...it's a tough thing keeping them
>> hushed form picking up any sort of noise floatng around the power buss.
>>
>> Also try putting the filter in a rack without any alternating current
>> sources or modules whih have microps, especially Harvestman. This
>> improves things a lot. As a last resort, consider the purchase of the
>> Plan B cases when they are released Q1 2009. All of our ground
>> terminations, from every terminal on the busboard lead directly to the
>> ground source on the PSU - no daisychaining!
>>
>> - P
>>
>> --- In PLAN_B_analog_blog@yahoogroups.com, "theglyph2000"
>>
>> <theglyph.aaron@...> wrote:
>> >
>> > My model 15 can be heard through my FrequenSteiner through the power
>> > rails. Not a big deal but just curious.
>> >
>> > The 15 and the AFG are working f@#$ing great for me! Peter and Mike
>> > are doing it right!!!
>> >
>> > Cheers,
>> > theglyph
>> >
>>
>
> 



-- 
http://www.myspace.com/anthonysaundershn