Quad 22 and Quad II
- Stereophonic preamplifier
- Tubes: Mullard ECC83 (x2) and Mullard EF86 (x2)
- Inputs: Tuner, tape, phono, etc
- Year: Aprox. 1957
- Push-Pull monophonic power amplifier
- Power output: 15 watts
- Class: A
- Power tubes: GEC KT-66 tetrodes (x2)
- Driver tubes: Mullard EF86 (x2)
- Rectification tube: Mullard GZ32 double diode
- Year: Aprox. 1955
Al least! One of my favourite tube desings. I have been waiting for a Quad
combo so many years... I have just received the units from the UK, thanks to
Nick T. Besley,
owner of the The Emporium. All the units look great. The first thing that has
impressed me is the quality of construction of the units, specally the circuit
of the preamp. I haven't heard them yet. But I hope I will do it next week-end.
Keep tuned on this pages to see how things are going.
Abril 18th, 2000. The information available on the net about these
wonderful units is massive. I would like to highligth one site. It is called
Quad World. There you will find everything you need: schematics, tweaks,
history, a lot of images, etc.
Of course, you can contact
Quad Hi-Fi, the
manufacturer of Quad products. Quad has a legendary technical service and there
you will find everything. They can also repair 22s an IIs. I have ordered the
original manuals of the units (10 pounds). That's what I call a good technical
I have just started to plan the upgrades to do to my units. As I said before
the trio is in excellent condition. So all the the work I will do will only be
changing some components. Upgrades will include:
- Substitution of all the componenets out of tolerances. To do this I have
selected the changes proposed by
Connections in their web site. This will de done with the help of Jorge
Buenos of Amptek.
- In order to connect a CD player to the 22 preamplifier it is necessary to
do some changes in the unit. There're several ways to do it and you could find
Quad World. I have chosen the "cleanest" option but to do it I have to
began relations with the antipodes.
Mike Coatham, from New
Zealand, builds a connector that fits in the TAPE socket of the 22 and allows
a CD to be connected. The price of the connector is 15 pounds (all included).
May 8th, 2000. I have just received the CD adaptor made by Mike
Coatham, from New Zealand. It is perfectly build and it also works perfectly on
the 22. If you want to connect a CD to the 22 preamp, this adaptor is what you
need and Mike is your man.
But now I want to talk about the sound of the Quad 22/II partnered with the Quad
ESL57.You can not imagine how I have enjoyed during this listening sessions. If
the sound of the ESL57 + Dynaco ST 70 was good, now the sound is superb. The
Quad preamp-amps are still in original condition (as you have read before I'm
planning a component upgrade) but I couldn't resist and after cleaning the units
I connect them to the Quad panels. The sound emerging from the panels is
excellent. The clarity and definition is greater than before. The musical
presence is also greater. The mid and low frequencies are better. Seeing this, I
wonder why hi-fi world and hi-fi components are now worst than before. If Peter
Walker built this wonderful components in the 50s, why we, with our greater
technical development, can't have better gear at modest prices?I know the answer
to my question. But I can't belive it.
But, let's talk about the sound.....As i said before mid and low frequencies are
now better. I wonder if one of the reasons of this improvement is the fact that
the Quad II are operating at an impedance of 15 ohms. I asked about this
question at audioasylum and somebody, I can't remenber who, explain the reason
why this happens. I will try more impedance combinations with the ST70. That's
all. Keep tuned to know more.
May 29th, 2000.At least I have had time to take some photographs of my
Quad units. Enjoy them!
- The Quad 22 and Quad II/II combo and a detail of the Quad 22 preamplifier.
- The Quad 22 from the back side and the Tape, CD (made by
Mike Coatham from New
Zealand) and Phono adaptors.
- The upper side of the Quad II circuit and the lower side of the same
- The Quad II power amplifiers and a detail of one of them.
- The another Quad II power amplifier and the quad plate where you can see
the serial number of this unit: 52147.
- The another quad plate with serial number 56199 and a detail of the tubes
used in Quad II. First, two Mullard EF 86 and on the back the GEC KT 66.
- Two images of the Quad II circuit.
Next episode: Modifying the Quad combo with images and explanations.
August 14, 2000. After intensive listening sessions during my holidays
of the Quad 22/II combo partened with the
ESL57 speakers and after receiving many emails about modifying these units,
I have decided to leave them without changes. Changes will only be made when a
componenet is out of tolerance. The sound from the Quad is so good that I think
that It couldn't be improved changing components. Also, it seems that there's
some kind of synergy between the components in the units that were chosen
looking for their behavior in the whole context of the amplifier. So.. things
will remain the same..