Ergo-Ella

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Ergo-EllaSlamDunkc.jpg


On the right:
All the AC stuff - IEC connector, transformers, power switch
power transformer matrix:
-1 large one for B+ and 2 small ones for filament supply
- terminal strips allow easy switching and adding/subtracting voltages for many circuits, KT88/2A3 PP, 300b or what-have-you SE

On the left:
All the DC stuff - FCUPS (film cap universal power supply), ABS (active bias supply), input filter caps
- FCUPS: all film caps power supply in a package comparable in size to toxic electrolytics.
- electronic choke on board with equivalent 500h allows use as virtual battery supply.
- ABS modules. These lock the bias of each tube so anode current is in perfect balance so no DC goes across the OPT core.
- FCUPS/ABS Protection Link. Any fault with a tube - runaway, whatever, Protect shuts dowe B+

Down the middle:
All the signal stuff
- includes adapter plates so completely configurable from 6 to 8 tube, SE or PP, octal, UX4, noval or blank out one section with included cover plate.

More tomorrow. Playing now. Ella would say: "It don't mean a thing if it ain't got swing." Wish she was here to hear this.
DIY - Done Right!
 
Ergo-Ella and a Power Supply that Delivers Like a Fire Hydrant

Questions from customers are good because they remind of features not yet discussed:
Why doesn't the Ergo-Ella have dual-mono power supplies like the previous Ella?

1. Actually the power transformer does have dual secondaries, both being connected in parallel to the FCUPS. This gives a very low output source impedance from the power transformer and power on demand
2. The FCUPS is set to run in virtual battery mode. It has the energy storage equivalency of about a 2 FARAD capacitor but the delivery and recovery speed of a 500h choke!
3. The point of a dual mono power supply is to avoid intermodulation effects between channels due to voltage sag. As per above you can see this is never likely to happen with paralleled HT feeds and the FCUPS.

This one single supply delivers like a fire hydrant compared to the two garden hoses of a dual mono supply.

If you already own an Ella, consider installing the FCUPS and ABS.

DIY done right!
FCUPS.png
 
Transformer Temperature Gain - AC from the Wall Socket vs Isolation Transformer

DC offset appears at the wall socket, riding on the back of the ACv we need. Of course a little DC across the transformer quickly decreases efficiency and raises the temperature core. When we apply the Auto Bias Modules in the Ella we immediately note better sound -- less strain, wider bandwidth -- because no DC is allowed to flow across the output transformer.

Today I ran the power transformer of the Ergo-Ella first plugged into the wall socket, then plugged into a huge isolation transformer we have here. I've previously measured 0.4-0.5DCv at our wall socket.

Our ambient room temperature is 34C today.
After 1 hour:
from wall socket: +24C
from isolation transformer: +21C

Next we will setup a three way comparison w/wo DC Blokker and direct from the wall.
DIY - Done Right!
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.