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Cole LCR Phono Stage

LCR COLE 600Rupdated

 

Power supply

  • 4 pcs 1k Kiwame 2w
  • 5 pcs 600r 2 w Kiwame
  • CCS module x 4 w/4 x 200r Dalee .25w
  • 5 pcs BG 150/350 VK
  • 1 pc 6.8uf/600v Obbligato oil

Signal Path

  • 2 pcs 600r S&B LCR
  • 2 pcs .047 silver mica
  • 2 pcs 0.5w tantalum 1m
  • 2 pcs 0.5w tantalum 50k
  • 2 pcs 1w 49r Dale
  • 4 pcs 100r carbon comp
  • 4 pcs 22uf/350v VK
  • 2 pcs Obbligato 2.2uf
  • 2 pcs 2m2 metal film
  • 10r x 2 tantalum .5w
  • 100r x 4 Dale .5w

Tubes

  • EZ80 x 1
  • ECC88 x 2

Other Parts

  • pcb w 2 sockets 9pin
  • pcb w 9pin sockets and ps caps
  • power transformer and cord unit
  • .5mm wire and teflon tubing
  • 20cm .1mm silver wire and teflon tubing for ground buss

ColeLCR06

 

Cole-MC220

Cole3

 

 

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Django Mini Passive Volume Controller

django-mini-volume-control-black-600x600-600x600

INTRODUCTION

ONLY $556 to have a great sound volume control. Expandable for more features. Very easy to build.

Premimum quality parts – supermalloy TVC, Japanese Seiden switch, Silver RCA. Solid aluminum chassis and knob.

Silver face plate version

 

EASY TO ASSEMBLE

Chassis preparation:

  • drill 1 hole on the front panel for the switch
  • drill 4 holes on the back panel for the RCAs
  • drill 4 holes on the bottom plate for the feet
  • drill 4 x 2.5mm x 6mm deep holes at the back of the face plate and cut thread with a tap to mount the TVC.

Soldering: It’s fairly easy.

Django Mini Volume Control Wiring Instructions

 

Pricing: $556 – $772

shipping $24-46

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Class-A 12AX7 MM Phono Stage (47dB, compatible to 40/51/56dB)

12AX7 Phono
Inside 12A7 phono

 

Back of 12AX7 phono
Frequency response of 12AX7 Phono
Distortion measurement of 12AX7 phono

Price includes four tubes and capacitors upgrade.

Standard package is 12AX7 + 12AY7 to get 47dB gain.

You can replace 12AY7 with 12AU7, 12AY7, 12AX7 to get 40, 51 or 56dB gain. See below for more information.

 

Design Concept 

Pure Class-A all vacuum tube design with zero negative feedback

Compatible with 12AX7 + 12AU7/ 12AY7/ 12AT7/ 12AX7 for different gains and different sounds.

 

Premium Quality Parts
  • Premium power transformer to ensure high performance, low noise and high reliability,
  • Kiwame resistors at important postions
  • Obbligato premium film gold capacitors to improve tranparency and clarity

Adjustable Gain 

Why do we need adjustable gain? Phono cartridge manufactures produce their own specification with different cartridge’s output level and impedance.

How to make gain adjustable? Typical approaches usually sacrifice sound fidelity. (Note 1)

Therefore we use a different approach – adjusting gain level by changing tubes, therefore there’s no uncessary components that usually distort the sound.

Tubes Gain level Application Sound Availability
12AX7+12AU7 +40dB May need another line preamplifier (with +10dB to +20dB gain) 12AU7: linear or well balance sound. Popular NOS or old production are still easily accessible
12AX7 + 12AY7/6072A +47dB Suitable for most MM cartridges 12AY7: very warm and smooth
12AX7 + 12AT7 +51dB Suitable for low output MM cartridges fast dynamic sound with punchy bass
12AX7 + 12AX7 +56dB Suitable for ultra-low output MM cartridges and some MC high output cartridges of +1mV. 12AX7/ECC83 Telefunken is still available though hard to find

 

Zero Negative Feedback topology 

Simple one way feed through circuit arrangement to preserve simplicity in design. By not aiming to lower the distortion with negative feedback we instead design the tube circuit to work into pure class-A and let this linear spot bring out the best no manipulating sound.
The harmonic distortion is less than 0.1% at 4mV input and distortion figure will reduce nicely in linear proportion to the input signal level.

Layout

Internal construction of this phono is very simple, elegant and carefully laid out for symmetrical signal between left and right channel.

 

Dimension

19 x 26 x 10.5cm (W x D x H) *

Shipping Weight
4.0kg *
* All specification are subject to change without prior notice.

 

Specification

Frequency Response according to RIAA standard
+/- 0.5dB from 20Hz to 20KHz
Total Harmonic Distortion with 4mV input signal
less than 0.1%
S/N ratio (SINAD 20mV input, 400Hz & 30KHz filter on)
-82dB
Input Impedance
47K ohm
Output Impedance
600 ohm
Gain
+40dB to +56dB adjust by changing output tube (standard +47dB from 12AX7 + 12AY7)
Circuit arrangement
All vacuum tube 2 x 12AX7 (input), 2 x 12AY7 (output)
RIAA network
R/C zero negative feedback type
Bias Operation
Pure Class-A
Maximum input level
20mV from 20Hz to 20KHz
.

Note 1: Typical approaches usually sacrifice sound fidelity.

1) adjust negative feedback level. The higher dB in negative feedback, the lower the gain. This works like a dream, a nightmare dream. Not only it changes the gain, but it also change the output impedance, frequency response, harmonic distortion, phase shift etc, but because it only requires a few resistors (or trimmer pot) to implement, the cost saving is abundance, thus utilize in many phono stages nowadays.
2) attenuate the signal path of the circuit. This strategy is “Lazy Man” solution that works very much like first method but instead of intruding NFB circuit, it just like adding potentiometer to signal path. Dumping signal away from the next stage and add unwanted impedance into the signal path. Increasing signal impedance means increase noise, reduce bandwidth, reduce current drive. 

 

Link to online store:

Store

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Django+ Passive Preamplifier

Django-front-600x600

INTRODUCTION

Beautiful chassis and knob, supermally TVC, Japanese switches, silver RCA and silver hook up wire, shaft extensions are employed to shorten the signal paths.

Available in kit form or assembled.

Internal View
Internal View
Back Panel
Back Panel

 

 

SPECIFICATION

Input: Maximum 6 pairs RCA / XLR

Output: 2 pairs RCA/ XLR

One switch for additional 6dB gain

One switch for ground connection

One switch for XLR/RCA output

 

Shipping rate:

US/Canada/Europe/Australia/NZ/ Japan:  $82
South East Asia : $40

 

Please click below links to read more:

Django Assembly Manual and Technical References

 

 

Pricing: $1130 – $1280

shipping $40-82

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Django Passive Preamplifier (w/ Remote Control)

Django-Remote-1-main-600x600[1]

INTRODUCTION

Premium quality parts are used : supermalloy TVC, silver hook up wire, silver RCAs, solid aluminum chassis and beautiful chrome on brass knob. A compact remote control is included.

 

BASIC FUNCTION

  • Volume control: 0 to -46dB, 23-steps
  • Remote control and manual control

 

OPTIONAL FUNCTION

  • Select input device (can connect up to 6 devices by RCA or XLR cable Note 1) by hand or by remote control.
  • Connect to more than one amplifier by RCA or XLR cable
  • 6dB gain
  • Break or connect output grounding
  • Connect to external ground wire

 

REMOTE CONTROL OPERATION

  • One button to increase volume
  • One button to decrease volume
  • One button to select input (need to press “enter” to confirm)

 

MANUAL OPERATION

  • Turn the knob to adjust volume.
  • Press the knob (don’t hold it) then turn it to select input, then press it again to confirm.

 

ASSEMBLY OPTION

  • Basic kit is a truly DIY kit. The front panel is silver in color with no hole and no cut out. Back panel is black with no hole.
  • Add $100 to have the front and the back panel drilled and installed with parts.
  • Add $200 to have a ready-to-use unit.

 

SHIPPING COST

Shipping weight is 5kg.

 

Note 1: The remote control board support maximum 6 pairs RCAs, or 5 pairs RCAs + 1 pair XLR, or 2 pairs XLRs (no RCA)

 

Pricing: $690 – $1070

Shipping: $35 – $70

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