Kenwood M1 power amplifier

[camtwister]

https://i.postimg.cc/wBWHy5G1/1604844072818.jpg (https://postimg.cc/06JhhSxv)

For private sale is a Kenwood M1 power amplifier.

The amplifier is in working condition.
This black box will give you 105W into a nominal 8.
The damping factor is monumental and the bass grip is superb.

Power output: 105 watts per channel into 8Ω (stereo)
Frequency response: 1Hz to 300kHz
Total harmonic distortion: 0.005%
Damping factor: 1000
Input sensitivity: 1V
Signal to noise ratio: 120dB
Speaker load impedance: 4Ω to 16Ω
Dimensions: 440 x 112 x 324mm
Weight: 9.1kg

This particular unit is a 220V European version.

https://www.vintageshifi.com/repertoire-pdf/pdf/telecharge.php?pdf=Kenwood-Basic-M-1-Brochure.pdf

https://www.hifiengine.com/manual_library/kenwood/basic-m1.shtml

http://www.hifi-classic.net/review/kenwood-c-1---kenwood-m-1-367.html

The amp is 35 years old.

The price is £199.
Payment via PayPal, please.
Carriage is extra to this, to be covered by the buyer.
Thanks.

https://i.postimg.cc/QNzGrx2r/1604844072810.jpg (https://postimg.cc/0r7HYx5t)

https://i.postimg.cc/Rhyj1X70/1604844072808.jpg (https://postimg.cc/Pvb3TbFG)

https://i.postimg.cc/wBgnktmD/1604844072815.jpg (https://postimg.cc/dhNWsVn0)

https://i.postimg.cc/JhxvY1Nv/1604844072817.jpg (https://postimg.cc/GBBXHnSx)

https://i.postimg.cc/tCV0RGbn/1604844072813.jpg (https://postimg.cc/8jDXw3jT)

https://i.postimg.cc/RFsrhMqK/1604844072803.jpg (https://postimg.cc/sQhH0CYg)

https://i.postimg.cc/KjTyH6vT/1604844072820.jpg (https://postimg.cc/m1Tqc69Z)

https://i.postimg.cc/wBWHy5G1/1604844072818.jpg (https://postimg.cc/06JhhSxv)

[camtwister]

A lot of juice for the money.

[Lawrence001]

What's the Sigma Sensor thing all about?

[camtwister]

Sigma Drive does not have to be used to enjoy this amp.

However, all of the answers are available here:

http://www.cieri.net/Documenti/Kenwood/Documenti%20tecnici/Kenwood%20-%20Sigma-Drive%20Technical%20Guide.pdf

In short,"Kenwood's Sigma Drive has been widely acclaimed as an effective means of providing optimum speaker control and an extremely high damping factor right up to the speaker input terminals. In addition to the normal speaker leads, a special 'Sigma' connection feeds distortion products caused in the speaker wires and in the speakers themselves back into the amplifier's NFB loop for effective compensation. The result is a total control over the speaker's behaviour, with optimum damping of unwanted speaker movement."

This is how you use the Sigma Drive, if you wish:

https://i.postimg.cc/QdSjG5cx/Screenshot-20201118-183435-Drive.jpg (https://postimg.cc/SnXBcnZw)

https://i.postimg.cc/43dsJd1v/Screenshot-20201118-183454-Drive.jpg (https://postimg.cc/pmggCP4y)

[Filterlab]

How bizarre, never seen anything like that before.

[camtwister]

The speaker output terminals don't accept banana plugs, but to reiterate, it can be used with conventional speaker wiring.
The review below evaluates the amp without the Sigma Drive employed.

"It is satisfying to find this calibre of performance at what must be considered very moderate prices in today's market."

http://www.hifi-classic.net/review/kenwood-c-1---kenwood-m-1-367.html

[Lawrence001]

I was wondering how they got a damping factor of 1000. Paper here but it's over my head:

https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.cieri.net/Documenti/Kenwood/Documenti%2520tecnici/Kenwood%2520-%2520Sigma-Drive%2520Technical%2520Guide.pdf&ved=2ahUKEwitk--P-4ztAhVklFwKHdqOAM8QFjAAegQICRAB&usg=AOvVaw1iqE84cuo5czHmtYzCgyEF&cshid=1605732656971

[camtwister]

Christmas bump.
Ho ho ho.

[camtwister]

Sold.