Babelfish M25, SissySIT - general building tips and tricks

Official Court Jester
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equal Rdc means same coil in both cases

LPC (lower nickel) is made of half common (Fe-Si) laminates and half Nickel , stacked alternately

HPC is made with all Nickel laminates

difference in inductivity is confirming higher permeability of Nickel , and we know that same is having lesser hysteresis , thus more details in sound

also higher inductivity means higher impedance , thus easier load on input buffer
 
Yes now I can relate with my physics knowledge. Great, thanks for the explanation!

Now for those HPC's to arrive. How long did it take for you to get these from Cinemag? I ordered and paid at the beginning of February. They are not responding to my emails.
I have now received my Toroidy Audio Grade 300VA mains transformers, so only some small parts left for a PS and some IEC inlet, etc.
 
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I only have the High-Nickel version of the Cinemags in my SissySIT. In the M2, I had the customary Edcors.

What I can confirm so far after the first week or so of listening to the amp - it is much more detailed than my M2, and by far the most detailed amp I have had in my current system :D

Also, I put an energy consumption measuring device between amp and wall socket yesterday ... and after fully heating up for a few hours, energy draw for the stereo amp maxed out at about 285W :eek: - I could still hold my hands on the heat sinks for at least 5 seconds, but I think I should dial back the bias a bit :p

Best regards,
Claas
 
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Joined 2004
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Yes now I can relate with my physics knowledge. Great, thanks for the explanation!

Now for those HPC's to arrive. How long did it take for you to get these from Cinemag? I ordered and paid at the beginning of February. They are not responding to my emails.
I have now received my Toroidy Audio Grade 300VA mains transformers, so only some small parts left for a PS and some IEC inlet, etc.

:yawn: still waiting on Cinemags since early Feb as well :yawn:
 
Official Court Jester
Joined 2003
Paid Member
I only have the High-Nickel version of the Cinemags in my SissySIT. In the M2, I had the customary Edcors.

What I can confirm so far after the first week or so of listening to the amp - it is much more detailed than my M2, and by far the most detailed amp I have had in my current system :D

Also, I put an energy consumption measuring device between amp and wall socket yesterday ... and after fully heating up for a few hours, energy draw for the stereo amp maxed out at about 285W :eek: - I could still hold my hands on the heat sinks for at least 5 seconds, but I think I should dial back the bias a bit :p

Best regards,
Claas

if that measuring device of yours is not overly optimistic, count on BigBadaBoom!!! anytime soon , simply because P channel mosfet isn't exactly made for almost 70W of heat!!!!!!

regarding Cinemags ..... my guys got them on start of Sissyfrenzy pretty fast , but now everything is slower

I believe not because of moi , most likely some massive order ..... maybe Pa, maybe not

me - being lazy and slow :rofl: - still didn't ordered two pairs for my personal needs
 
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The diagram below shows the power curve over time for my SissySIT build after rebiasing.

Ignore the "short spike" to the left of the picture, that was just my boys playing on the Xbox ... :D
You can see the bias rising with the warming through of the amplifier. After reaching steady-state, the jitter of the curve is due to fluctuations of wall voltage (and therefore rail voltages):


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The unit on the y-axis should really be W instead of Wh, but that's a bug in the graphing routines of the house control system I'm using ...



Here is some transient detail of the starting phase of the amp:


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You can see pretty well the action / time constant of the opto bias scheme combined with of the 3300 µF bias spreading capacitor. This regulates the bias rise in the first one or two minutes; after that, it's more or less due to the amplifier warming up.



Best regards,
Claas


P.S.: I did wait for my CMOQ-4HPC from mid-November to beginning of February ...
 

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Official Court Jester
Joined 2003
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nice

I realised that , besides Edcors (same as for M2 ) , I also have Jensen repeaters with wires (so , no PC mount) - perfect to put them in , while waiting for my own Cinemags

though , still need to order them..... lazy ZM ....... or is it that funny named German guy again playing with my memory

:clown:
 
What are the connectors that you use between the pcb boards as well as the Sissy boards? They look removable and I have been looking for these.

Hi,
They are just soldered directly to pcb. Signal (not there yet) have spacers placed to pcb only to make soldering easy without removing pcb's from heatsinks when adding signal wires. Those came along with ZM's kit and are really ment for input buffer (take a peek at schemas).

But, you can find some 80A rated small 3,5mm bullet connectors used usually in drones and they are quite cheap at hobbyking.com or ebay, just an idea I have been thinking couple of times? Just add some shrinking tube to isolate them.
 
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Slight mess up and question on small electrolytic caps.

Finishing up my boards, and just soldered in one C5 cap, which schematic shows as 10uF. I soldered in one of the blue 10uF caps that came with the kit. (Panasonic?) I thought it odd when I could plainly see it was by passed with Zenmods favorite Silmic by pass. Then noticed there was not enough 10uF caps to populate all the other places they were called for.

The Silmic in my kit is 22uF, but I am betting dollars to donuts I missed an update where it was changed from 10uF to 22uF? If so, I need to remove the blue 10uF and re install the Silmic. I know it was used for a special reason, usually sonically, especially since by passed. Arghhhh very tiny pads.

Or is this a M25 vs SissySit thing? My kit was originally a M25, but was sent extra parts for either and decided to do SissySit first.

I swear, I could tear up an anvil with a rubber hammer some days....

Russellc
 
Official Court Jester
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I'm sure that I wrote somewhere of sending 22uF Silmics , even if C5 are marked 10uF

so , C5 are 22uF Elna Silmic II , bypassed with fancy 1uF Philips MKC ....... and C5 position is clearly labeled as Silmic on (both) schematic(s)

rest of electrolyt caps are all Panasonics ( 4 positions 10uF and one 3.3mF)

anyway , just put blame on me , and I'll blame Pa, as always

:clown:

pads - to desolder tem easier - just add solder - biggest blob you can manage - better transfer of heat

when you pull part successfully out , just use solder sucker or solder wick to clean pads of solder
 
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Its good, all removed fine. correct ones in.

Another query, my boards were ordered as M25, so there is a C3 SMD cap installed. Looks like it is out of the circuit if resistor isnt there, which it isnt. (using Cinemag). Is it fine to leave, or should I remove it? Or am I about to take rubber hammer to another anvil? Also wondering what tiny square white caps are for?

Russellc
 
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