Ergo-Ella DIY HiFi Supplywww.diyhifisupply.com

Table of ContentsChapter 1-Introduction............................................................................................................................................................................................................3Chapter 2 – Specification and Parts........................................................................................................................................................................................6Chapter 3 - Installation Notes.................................................................................................................................................................................................8Chapter 4: Power Transformer Connections........................................................................................................................................................................10Chapter 5: Filament Transformer and Ground Connections................................................................................................................................................14Chapter 6: Output Connections............................................................................................................................................................................................16Chapter 7: Power (FCUPS) and Bias Supply (ABS) Connections.......................................................................................................................................18Chapter 7b – : FCUPS and ABS bias supply testing............................................................................................................................................................20Chapter 7C: ABS Supply Testing.........................................................................................................................................................................................22Chapter 8: Signal Path Parts Connections............................................................................................................................................................................22Chapter 9 – Operational notes..............................................................................................................................................................................................24Chapter 10 - Final Words and Tweaks.................................................................................................................................................................................26Appendix...............................................................................................................................................................................................................................29

Chapter 1-IntroductionErgo: The Ergo-Ella is just one example of what can be built on the Ergo chassis. The Ella, LD Stereo, Joplin, and Lux can all be built on this chassis.

Features:

Mechanical Ergonomics

* Around: Bamboo Wood front and side panels. This wood is very hard, resistant to moisture and has a great tactile quality. It's natural resonance has a musical tone. Bamboo wood is renewable and typically harvested every 4 years. Back panel is aluminum and (left to right) has IEC connector, provision for both RCA and XLR inputs, 4 speaker binding posts

* Left: 3 Power transformers (1 main and 2 filament) are mounted on the left and lineup with the IEC input. Terminal blocks are provided for easy voltage configuration, both input and output. There is also space provided to mount 2 of the FCUPS and filament supplies.

* Center: tubes go here (or optionally some standup film caps). Tube sockets are mounted on sub plates and provided for 8/9 and 4pin. So you could have 4 x 6550, 2 x 6922, 2 x 6SN7 for the Ella, or 2 x 5AR4, 2 x 310a, 2 x 300B for the LD91 stereo, or 2 x 5AR4, 2 x EF86, 2 x 5687 and 2 x 300B for the LUX or 2 x 6922, 2 x 6CG7 and 2 x 2A3 for the Joplin. Etc etc

* Right: space for 2 standup 10uf film caps and 2 output transformers

* front: nameplate and push button power switch.

Signal Ergonomics

AC supply currents stay to the left, power and signal meet in the middle and output signal stays to the right

DIY Done Right!

Ergo-EllaDue to reasonable input sensitivity, the Ergo-Ella can be to a line level source via a passive Preamplifier. If connected using the Django TVC the sonic result will be even better. The circuit is comprised of three stages: 6922 as the first SRPP stage, followed by 6N8P (6SN7) driver stage with EL34/KT88/6550/KT100 as the final power stage in classic push-pull class AB configuration. This is a classic circuit and the sonic performance is very high due to the design of the output transformer, tube circuit optimisation and years of experience in development.

In addition, the power supply does not sag during transients as it is completely dual mono fed from a common low source impedance power transformer. It uses fixed bias design with external individual bias adjustment for each EL34. The EL34 is rugged and sweet sounding. Due to the robust power transformer and output transformers, 6550/KT88 can also be used with a resulting increase in output power to about 50+ watts, however many feel the EL34 can not be bettered for sound quality.

Ergo Ella uses the ABS (active bias system), a very worthwhile addition since it keeps the DC current through the output transformer to a minimum and thus maximizes full frequency performance The powersupply uses our Universal Film Capacitor Power Supply with Schottky enhanced high tension rectification and only film capacitors (no high distortion, opaque sounding electrolytic capacitors are used at all).

Low NFB with bias regulation ensures optimal tube regulation and sound. 40-50 watts (remember, these are tube watts) means you don't need new high-efficiency speakers and that your current speakers will be driven to shake and quake levels. Dual triode input stage and soft start are just some of the user-friendly features. The Ergo-Ella comes with a remote, instruction manual, and all tubes (if ordered). The chassis is pre-assembled, PCBs with pre-mounted components; power transformer M6 lamination in the output transformers. The OPT are the soul of any tube amp and the latest generation is CNC wound for perfect lay, low capacitance and very wide power bandwidth. The large chassis and generous size dissipates heat evenly; it is normal for the chassis and power transformer cover to feel hot due to the efficiency of heat transfer from critical parts. The unit looks good as well. The combination of SRPP, and very low NFB adds up to truly high end sound. Dynamics are impressive, as is openness and sound-staging. Its performance belies its price many times over.

RequirementsThe kit builder needs to have basic soldering skills and be able to read and understand the wiring diagrams presented. Refer to the text and diagrams at each step throughout the manual and ensure you double check all wiring at each stage. It is also advantageous to refer to the circuit diagrams at the back of the manual throughout the build.

WarrantyThe kit cannot be returned for a refund. Defective parts will be replaced provided they are returned within 30 days of purchase and are confirmed defective and not misused. No further Warranty is expressed or implied. This is to protect you the buyer to be assured of receiving a brand new kit and not one that has been returned by someone else which may have been misused.

Disclaimer

Always unplug power when connecting/disconnecting wires.

DIY HiFi Supplywww.diyhifisupply.com

This manual is the property of DIY Hifi supply Ltd and may not be reproduced or distributed by any means in whole or in part.

Right to use the manual for the construction of the Ergo-Ella kit is granted to the purchaser of the kit.

WARNING: The high voltages present in this kit can kill and the high operating temperatures can burn. Observe all precautions and never connect the kit to an electrical supply until it has been fully assembled, checked and ready for testing. You assume total responsibility and liability for the use and operation of this kit both for yourself and people around you. Confirm that large capacitors are discharged before working on the amplifier

Chapter 2 – Specification and PartsSpecifications

• Power output: 45 Watts x 2, RMS @1Khz with EL34 Ultralinear connection, more with other tube sets• Frequency response: 6Hz to 60KHz (-3dB@10W)• Total harmonic distortion: < 1% (40W@1Khz)

Input sensitivity : 550mV, • INPUT IMPEDANCE: 100k ohms• OUTPUT Speaker IMPEDANCES: 4 , 8 and 16 ohm• Signal to noise: >100dBA• POWER CONSUMPTION: 110/220V AC, +- 10%, 90W 85W• CONTROL FUNCTIONS: Power On/Off, • INPUT INTERFACES: 1 groups (RCA) • OUTPUT INTERFACES: 4 Groups 4-way binding Post• Vacuum tubes: 6922 x 2 or equivalent, 6N8P x 2 or equivalent, EL34 x 4 or 4 x KT88, 6550, KT100

• Dimension (mm) and weight: 340(L) x 410(W) x 230(H), 25kg net

UnpackingRemove the bottom cover from the chassis, take out the loose kit parts and check against the list. Some minor variations in value are perfectly acceptable (ie 47k instead of 43k etc)

Parts List

Parts supplied according to Level 3 or Ella Max – whichever was ordered

Qty Item Level 3 Max Items installed in the chassis:4 1N4007 diodes P P4 P Qty Item Level 3 Max2 P P 8 Speaker binding posts (6 red, 2 black) Standard Copper

2 P P2 Gold Gold

4 P P 1 power switch P P4 P 1 IEC power socket with fuse P P8 1K AB Carbon Composite P P 2 ABS (Active Bias System) controllers P P1 P P 1 Film Cap Universal Power Supply (FCUPS) P P2 P P 1 power transformer P P

2 P 2 Filament transformer P P2 P P 2 Output Transformer P P2 P P 6 Tube Sockets (8 pin) P premium1 P P 2 Tube Sockets (9 pin) P premium6 P 2 Obbligato oil film caps 10uf (mounted topside) P P

2 P P 1 Obbligato Film Capacitor 47uF/500V P P2 Film Caps 10uf P P

2 0.47uF / 630V (SCR) Output RC P P2 Premium Obbligato 0.47uF / 630V P P4 Premium Obbligato 0.1uF / 630V P Options: P P2 P P 2 6922 P P

2 6N8P P P1 Power LED & Resistor & Diode 1N4007 P P 4 EL-34 P P

3m 0.5mm silver wire P P3m 1.0mm silver wire P P1.2m shielded signal cable P P

10R Kiwame 2W 1/2w tant24R Kiwame 5W

100R Kiwame 2WRCA jacks Machine screws, nuts & washers chassis,

220R Kiwame 2W470R Kiwame 2W 1/2w tant

1K Kiwame 5W15K Kiwame 5W30K Kiwame 2W 1/2w tant47K Kiwame 5W51K Kiwame 5W68K Kiwame 5W100K Kiwame 2W 1/2w tant1M Takman Metal Film

teflon100pF minature (variation allowed)

Chapter 3 - Installation NotesRecommended SolderIt is recommended that solder with flux, designed for electronics is used. This usually has up to 2% of Silver that prevents the joint from becoming brittle over time. It provides a much stronger solder joint but can be difficult to work with due to its lower ‘wetting’ properties, it does not flow as easily. Some electronics solder has a small amount of copper instead which has very good ‘wetting’ properties. Whichever solder you use, make sure that you avoid poor solder technique.

Solder TechniqueSolder means to apply the iron tip to the point that needs to be soldered to heat it and at the same time apply the solder. The iron and solder come together at the same time when soldering any joint or tinning a wire and the solder should start to flow evenly around the joint. Allow the solder to cool naturally and do not blow on it. The finished joint should appear shiny and not dull. Many problems are due to poor solder technique. Clean the iron tip regularly on a wet sponge between each soldering step.

Connections Always wrap the wire around the connection point to make a good mechanical connection.

Connect means to dress a wire by stripping off enough insulation and soldering it to the connection point or first tinning the wire. When connecting a wire to a valve base pin it is recommended that enough insulation be removed so the wire can be wrapped around the pin to form a good mechanical joint before soldering. When attaching wires to any of the PCB’s or switches you should strip off a small amount of insulation and then apply solder to the exposed wire to tin it before fixing it to the PCB.

Tips for Successful Kit BuildingRead each chapter through before starting it: You should familiarize yourself with the sequence of instructions before starting a chapter. Also, many chapters have helpful pictures and drawings scattered through them that will help you understand the written instructions.

Follow the sequence of instructions: These instructions were designed to make assembly as simple as possible and minimize interference between assembly steps.

Identify and measure parts: Be sure of the identity/value of each part before you install it. Many kit builders actually measure the value of resistors with a multimeter before installing them. Note: the parts in your kit may not look exactly like the ones pictured here as suppliers of parts are sometimes different. Some supplied values may differ slightly in value from circuit diagram and are within tolerance for the circuit.

Follow the schematic: It is a good idea to have the schematic diagram of the unit nearby and to compare the instructions with the schematic.

After installation, check the instructions again: Once a part is installed, double-check the installation against the printed instructions.

Check off each assembly page when completed

Wire layout: Most of the power supply wires run lengthwise along the chassis. Most signal wires and grounds run crossways. Try to keep power supply wires close to the chassis and running perpendicular (90 degrees) to signal and ground wires. Signal and ground wires can be a little above the chassis plane. Twisting together signal pairs and power supply pairs can also help to reduce hum and noise pickup. Do not twist signal and power supply pairs with each other. Pictures indicate which of the coloured wires to use.

Chapter 4: Power Transformer Connections

Chapter 5: Filament Transformer and Ground ConnectionsImportant: Twist the filament connection wires at least 3 turns to the inch to prevent hum and noise. Place in position as shown. Fit the Resistor and Capacitor for the RF suppression circuit to the 8 Ohm Speaker Terminal and the common speaker terminal as shown.

Chapter 6: Output Connections

Chapter 7: Power (FCUPS) and Bias Supply (ABS) Connections

Wire FCUPS and ABS Modules as shown below..

Chapter 7b – : FCUPS and ABS bias supply testing, heater voltage testingAlways observe polarity of test equipment to avoid damage.

When first powering up the Ergo-Ella, disconnect the wires from the FCUPS to the ABS.

Then power up the Ergo-Ella. Eventually all 3 LED on the FCUPS will light up about 1 minute).

Measure the DCV at the B+Out connector on the FCUPS (one probe to Chassis ground and one probe to label <<B+Out). It should be about 370-400V DC.

Measure the input AC voltage to the FCUPS at the input side of the FCUPS (one probe on each point labelled AC310V>>). It should be 300-330V AC.

Measure the DCV at the Bias -V Out label. It should be about -100-120V

Turn power off.

Always unplug power when connecting/disconnecting wires.

Turn power on.

Measure the voltages between pins 2 & 7 on the output tube sockets. The voltage should be 6.6V AC +/- 0.5V (it will drop back to 6.3V once loaded with the valve's heater.

If the voltage is significantly different you need to check the polarity of the heater windings from the filament transformer.

If the voltage is much too low it usually means one winding is connected in inverted polarity, causing the heater voltage to be low. Simply invert one of the windings from the heater transformer to correct the problem.

If the voltage is much too high it usually means a connection was made wrongly.

Finally measure the heater voltage to input and driver valve sockets (e.g. at the 6SN7 socket pin 7 & 8

Connect the 47uF film cap with 2 x 10uf top side capacitors to FCUPS as shown, connect the two 10uF capacitors in the chassis as shown.

Proceed to make connections for Shuguang style EL34 tubes as shown below. ABS comes preconfigured with bias set for EL34 tube operation.

Chapter 7C: ABS Supply Testing

If was all OK when testing the FCUPS (7B) then connect ONE ABS to FCUPS. Check that it powers up normally. After 2 minutes there should be about 0V at the ABS connector labelled 'B' in the diagrams.

Then disconnect that ABS module and proceed to test the other ABS module in the same way.

Always unplug power when connecting/disconnecting wires.

Chapter 8: Signal Path Parts Connections

Chapter 9 – Operational notesDo not yet insert the tubes!1. Adjust the volume to lowest setting

2. Turn the chassis bottom facing up. Plug in the power and switch on the unit with the power switch. Watch for sparking, smoke or any condition that would indicate miswiring. If you have burned out a fuse, you can find the fuse that needs to be replaced inside the little drawer in the IEC that slides out from the backside. Replace with same value type as etched on endcap. If OK proceed to the next step. If not, check for mistakes.

3. Check power tubes, pin 5 (counting clockwise from the #1 pin indicated in the diagram) for -50VDC (-ve probe to ground buss, +ve probe to pin 5. (Since this is a negative voltage you may need to reverse the probes - check on a high range first). Takes about 2 minutes for bias voltage to stabilize.

4. Check the voltage between pins 2, 7 on each power tube for 6.3VAC 10%. AC range on your meter, one probe to pin 2, one probe to pin 7

5. Middle 4 tubes. 2 are 9 pin, 2 are 8 pin. Again counting clockwise from #1 pin. 8 pin tubes: As above for measuring ACV, check between tube pins 7 and 8 for 6.3VAC 10%

6. 9 pin tubes: Check pins 4/5 for 6.3vac 10%. One probe to pin 4, one to pin 5.

7. Check B+ on PS PCB for ~400v dc. Again to test DC V, -ve probe to ground buss, +ve (red) probe to test point. Turn off the power.

8. A: Turn over unit. Insert the 4 EL34 power tubes into positions shown by the picture..

9. .Double check all your connections and refer to the circuit diagrams at the back of the manual whilst doing so. Inspect all solder joints for completeness. Check carefully to make sure that small pieces of hardware or solder drops are not left inside the chassis. Reinstall chassis plate.

10. Turn unit over and insert the other tubes into their respective sockets (6922s and 6N8Ps). Do not connect input source and volume pot on preamp must be fully counter clockwise! To be safe you can attach a 10W 10 ohm resistor across each pair of speaker posts.

11. Turn on power. If all OK, turn off the power.

12. Connect speakers and sound source (i.e. CD player). You should never operate the unit with no speaker load attached or with shorted speaker outputs whenever signal source is applied.

13. Turn on the power and input signal. Adjust volume pot to desired listening level.

1. Heater wire limits: 5.7-6.9V

Distorted, low or poor quality sound1. bias is incorrect

Blown fuse1. Metal debris has fallen inside chassis and is causing a short.

2. Output tube damaged.

3. Filter cap damaged.

4. PS transformer has shorted internally or has been miswired for local voltage.

Output tubes glow bright red

1. PS voltage too high

2. bias incorrect

3. Output shorted or open when signal applied.

4. Old EL34s

Power Tube sets:1. EL34

2. KT88 and 6550

3. KT100

Adjust bias for above tubes as per:See Appendix

Chapter 10 - Final WordsThe Ergo-Ella requires about 50 hours running in especially if you are using new tubes.

Using more exotic NOS tubes can also improve and change the sound character of the amplifier.

USE IN A WELL VENTILATED PLACE TO PROVIDE AIR CIRCULATION.

CopyrightThis manual is copyright of DIY HiFi Supply www.diyhifisupply.com . It must not be reproduced or distributed in paper or electronic form.

Manual produced by: DIY HiFi Supply Ltd www.diyhifisupply.com

rev1.32

This is a finished Ergo-Ella with level 3 options and ABS module.

AppendixThe ABS come preset for EL34. To change, replace 10 Ohm Cathode resistors for Output Tubes as follows:

EL34: leave as is

KT88/6550 fit 8.2 Ohm (47mA)

KT100 fit 7.5 Ohm 52maNote: the higher the anode current, the more heat and stress. Always monitor heat and provide enough airflow around amp. Please note that suggested anode currents give the best sound. Higher settings are not needed due to the state-of-the-art power supply and bias control.

You do not have to change the cathode resistors just to operate the KT88/6550/KT100 and similar, you only need to adjust the resistors if you want to take advantage of the increased power form these Valves.If you keep the standard 10 Ohm Resistors the current will be set to 39mA regardless of the type of valve used and the high tension supply will be around 400V. Please check if this is compatible with the maximum ratings of the output tubes you wish to use.

In principle many valves with a basing and connection identical to the EL34 but different electrical parameters and sound can be fitted. While not tested the KT66 & KT77 should work as well, as should some recent so-called EL156 – which have actually the same socket pinout as the EL34 and hence do not fit historical EL156 Amplifiers.

Tweaks and things to tryAdvanced kit builders may wish to experiment with connecting Ergo-Ella’s output section to run in triode mode for lower output impedance and “triode sound” or in Pentode Mode for more power and the classic “Pentode Sound”. Schematic diagrams for these configuration are included below but not supported.

In Triode mode around 30W Output Power are available, while in pentode mode more than 60W are available when using the EL34.

Ergo – Ella Standard Schematic

Ergo – Ella Triode Mode Schematic

Ergo – Ella Pentode Mode Schematic