AUDIO NOTE
Integrated Stereo Amplifiers

Read consumer feedback on our Audio Note Custom products.

15 Watt SE 6550/KT88 Integrated Stereo Amplifier

PLEASE NOTE: The AN 6550/KT88 integrated amplifier is now supplied with a source selector allowing up to 3 source inputs as can be seen in the picture.

 

 

 

 

The amplifier shown above is also available in the new black chassis as seen in the 300B amplifier below.

The Audio Note 6550 integrated stereo amplifier yields about 15 watts in pure unblemished Class A, single-ended operation. It uses a single 6550 pentode per channel, one of the most popular and reliable pentodes ever designed in a single-ended arrangement. Each stage of the amp is operated in class A.

The AN 6550 uses a simple circuit, where both channels of the input fed directly to each half of a 6SN7GT double triode operating in an unusually high current mode, the gain control potentiometer is placed AFTER this first gainstage to allow the amplifier to be driven by any source with a minimum of noise introduced by this first stage.

The 6SN7GT input stage feeds a 12AX7 driver stage. The 12AX7 is a miniature double triode of high gain and in this circuit is configured in a SRPP (Shunt Regulated PushPull), which gives a gain stage with a very wide dynamic swing, low impedence and outstanding drive capabilities.

For the output stage the choice was made to use the popular and very rugged 6550 pentode. It is used within its limits and coupled to an oversized in-house designed and manufactured Audio Note output transformer with 4 ohm and 8 ohm taps.

No real compromises have been made within the component choice in the audio circuit, each component being of the best quality and being operated most conservatively, ensuring reliability and long life. Despite the low price of the kit the chassis and PC-boards are of a high standard.

With our Extreme Build version, you have the option of Audio Note Copper Foil (as shown below) or V-Cap Teflon Capacitors in the coupling signal path. Also employed within this amplifier are Elna Silmic capacitors on the driver board as well as used in cathode bypass for the output tubes.

Pricing:
 V-Cap Teflon coupling capacitors $2,940
Audio Note Copper Foil capacitors: $2,695
Fully assembled and tested unit as described above

Happy New Year Bill,

The Kit 2 is sounding glorious. I am not sure it is fully settled in as it seems to still be improving daily. But it has to be getting close. I got a nice NOS closely matched pair of Tung Sol 6550's on ebay for $177 and they are, for *me*, the bomb in this amp. I will keep one pair each of the new TS 6550's and GEC KT 88's. The new TS 6550's I got were cryoed. My first shot at cold tubes so I don't know how they are without the treatment. They are OK but the NOS TS's beat them handily in this amp. NOS tubes really sing in this circuit. I really wish you could hear it now. I will post a review in a few more weeks. I want to be sure it is fully burned in B4 I do that. Black Gates can take a long time to really settle in.
 

 

Kit 1 MK II
Integrated 2A3 or 300B amplifier

The Latest Version of the PQ Kit1 can be wired as a 2A3 or a 300B amplifier. It comes with copper brackets on the large double C-Core output transformers along with gold knobs as standard. We use the ELMA Selector Switch to select up to 3 sources.

So how do you improve on the already superb Kit1 Standard Edition?

We are lucky enough to have access to Audio Note's high-end double C-core output transformers that are used in the AudioNote finished products. We have incorporated these output transformers into the Kit1 and we call it the PQ Edition. These transformers are hand made on site at the AudioNote UK factory.

These remarkable transformers (Hi-B 0.15mm TRANS-300 series) have the effect of increasing depth and resolution; offering that true high-end SET sound across the full frequency range. The PQ Kit1 300B/2A3 also includes other upgrades as standard such as Black Gates on the driver and 300B (or 2A3) circuits, TKD volume pot, etc. (see list below).

Because the Double C-Core transformers are bigger than the TRANS-152 transformers used in the Kit1 standard edition, we had to make the chassis bigger in order to accommodate them - it is now 35mm wider than the original chassis.

We offer two different base kits for this range (see further down the page). Here is a list of the things that are upgraded as standard from the Kit1 Standard Edition Basic model:

• Stainless Steel Chassis (35mm wider than standard kit1)
• Audio Note TRANS-300 Double C-Core output transformers (Hi-B 0.15mm)
• Black Gate electrolytic capacitors on the driver & 300B/2A3 circuits
• Silver solder included
• TKD potentiometer

All current versions of the Kit1 are integrated amplifiers. That is, they can accept input from any standard line-level Hi-Fi component. A volume control is accessible on the front of the chassis. Output transformer taps of 4 and 8Ohm are available on the rear of the unit to make speaker matching easier. The mains transformer can be internally configured for many different countries. Upon request, multiple inputs can be accommodated via an additional input selector for the front panel. All necessary components are supplied in the kit, including valves.

The input stage consists of a 6SN7GT with a 5687 double triode driver stage running in SRPP. The power supply is a capacitor-choke-capacitor with a 5U4G HT rectifier.

Please enquire about hard-wiring options for drive and power supply boards. Also feel free to enquire about any extreme upgrades that may be available.

Audio Note are now providing copper frames as standard with their double c-core output transformers. The copper frames being non-magnetic improves not only RF influx, but also low level behavior as it does not short out the air gap.

Kit1 300B/2A3 - PQ Editions   Kit1 300B/2A3 PQ - STANDARD   $4,399USD The STANDARD kit is the starting point for the 300B/2A3 PQ Edition.  It comes standard with the following:   Audio Note TRANS-300 Double C-Core output transformers (Hi-B 0.15mm) Black Gate electrolytic capacitors on the driver & 300B/2A3 circuits TKD potentiometer Audio Note Aluminium-in-foil signal capacitors Black covers for the Mains and Choke Kit1 300B/2A3 PQ - SIGNATURE    $4,999USD This is the Standard PQ kit with the following upgrades:   Tantalum resistors throughout Audio Note Copper-foil coupling capacitors Audio Note AN-V signal wire