Kenwood KA-3500: Difference between revisions

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Stereo Integrated Amplifier Model KA-3500
"Stereo Integrated Amplifier Model KA-3500"


I've owned it since new, about 1974.
40W / channel into 8 ohms
0.2% THD
 
I've owned it since new, about 1974. I paid about $100 for it from Pacific Stereo in Walnut Creek.


It's been in storage a couple years while I moved.
It's been in storage a couple years while I moved.
Line 10: Line 13:
The lower set (B) are banana only.
The lower set (B) are banana only.


I added a pair of phono connectors to the AUX inputs, for back when I used this amp with a synth.
I added a pair of 1/4" phono connectors to the AUX inputs, for back when I used this amp with a synth.
 
Internally there is lots of space and it's very modular.
* X07-1470-10 Power supply and amp are on the main board.
* X08-1530-00 Input selection controls and phono preamp
* X08-1530-00 Preamp with control pots and switches and loudness and low pass filters
 
The preamp is implemented on two boards but it shows as one section in the circuit diagrams.
One board has the input selection switches and the phono preamp and the other has everything else.
 
I will NEVER use the phono input again so I could replace that board or at least bypass the phono preamp so that I'd have 3 line level inputs instead of two.
 
I'd love to replace the entire preamp section with something modern that includes a remote control.
Funny, the pots in this amp have detents so changing over to rotary encoders would not even change the feel.


== Recap ==
== Recap ==
Line 16: Line 32:
Thinking about recapping it.
Thinking about recapping it.


I found a service manual for it, so I have a complete parts list.
http://www.audioasylumtrader.com/ca/listing/Integrated-Amplifier-SS/Kenwood/KA-3500/Recapped-amp-updated-Integrated-Amplifier/113891
 
I found a service manual for it on http://www.Manualslib.com/, so I have a complete parts list.
 
Lots of details here on someone else's project: http://www.audiokarma.org/forums/index.php?threads/ka-3500-long-post-and-long-overdue.645600/#post-8586864
 
At this time I don't plan on touching the preamp.
I am adding a few extra parts to the quantities on the power/amp section though to cover the preamp.
 
=== Power amp / supply section ===


<pre>
<pre>
Qty uF V Digikey uF V hours
2 0.47 50
6 47 10
2 220 10
2 47 50
2 6800 42 493-8662-ND 6800 50 5000 $4.22 $8.44
2 330 35
1 47 100
1 330 16
1 220 50
19 $8.44
</pre>
</pre>
ELNA Audio Premium series
Elna "Silmic II" audio-grade capacitors are available from Digikey
Nichicon KZ premium grade acoustic series
"Orange Drops" are something harkening back to the early days of Gibson electric guitars so some people think they are still the cool thing to use.

Latest revision as of 20:20, 12 February 2017

"Stereo Integrated Amplifier Model KA-3500"

40W / channel into 8 ohms 0.2% THD

I've owned it since new, about 1974. I paid about $100 for it from Pacific Stereo in Walnut Creek.

It's been in storage a couple years while I moved.

Mods

I replaced the cheesy binding posts for the outputs. The upper set (A) are banana or wire terminals. The lower set (B) are banana only.

I added a pair of 1/4" phono connectors to the AUX inputs, for back when I used this amp with a synth.

Internally there is lots of space and it's very modular.

  • X07-1470-10 Power supply and amp are on the main board.
  • X08-1530-00 Input selection controls and phono preamp
  • X08-1530-00 Preamp with control pots and switches and loudness and low pass filters

The preamp is implemented on two boards but it shows as one section in the circuit diagrams. One board has the input selection switches and the phono preamp and the other has everything else.

I will NEVER use the phono input again so I could replace that board or at least bypass the phono preamp so that I'd have 3 line level inputs instead of two.

I'd love to replace the entire preamp section with something modern that includes a remote control. Funny, the pots in this amp have detents so changing over to rotary encoders would not even change the feel.

Recap

Thinking about recapping it.

http://www.audioasylumtrader.com/ca/listing/Integrated-Amplifier-SS/Kenwood/KA-3500/Recapped-amp-updated-Integrated-Amplifier/113891

I found a service manual for it on http://www.Manualslib.com/, so I have a complete parts list.

Lots of details here on someone else's project: http://www.audiokarma.org/forums/index.php?threads/ka-3500-long-post-and-long-overdue.645600/#post-8586864

At this time I don't plan on touching the preamp. I am adding a few extra parts to the quantities on the power/amp section though to cover the preamp.

Power amp / supply section


ELNA Audio Premium series

Elna "Silmic II" audio-grade capacitors are available from Digikey

Nichicon KZ premium grade acoustic series

"Orange Drops" are something harkening back to the early days of Gibson electric guitars so some people think they are still the cool thing to use.