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Parasound HCA-1206 Multi Channel Amplifier, Optimized For Stereo Only

This Parasound HCA-1206 is a multi-channel amplifier that intended for home theater audio setup.

No wonder this amplifier has 6-channel identical amplifier in one chassis, together with the THX certified label, it delivers 120-watt power per channel.

This amplifier is my fresh catch not long time ago after I got the Parasound DAC-1000 before. The condition is like new and I was thinking that this amplifier would be a match pair with my DAC since they are built at the same year.

And I was right! This amplifier is sound wonderful. It really matching with the DAC in term of the style and sound.

That is why, in this post, I will make this multi-channel amplifier optimized for use in the stereo system only.


I hope you are might wondering why the photo taken in this post is in the different place?

I usually take the photo on my working desk but in this post, the photos are taken on the floor, in front of my listening room. The reason for this is because this amplifier weight is very heavy. At least need 2 persons to carry this amplifier together. Since I don't have enough person to help me to move this amplifier, so I better put it anywhere that make me easy to work on it.

The input are 6 RCA single-ended type. All of them has individual gain level on top it. This is a great feature that might help balancing the sound level for each channel.

Channel 1 and 2 are intended for front-stereo channel.

Channel 3 and 4 can be bridged and become single channel.

Same with the channel 5 and 6 can be bridge as well.

Now let's see the components inside.








The weight contributor for this amplifier is the big power transformer. Then, the thick steel chassis with large heat-sink is come in the second place.

There are 2 row of final transistors line-up, each channel has 2 pair of transistors, so in total, there are 24 final transistors in one amplifier.







The cables arrangement inside is messy and this what I really like to tidy them up.

I inspect the components in more detail and found that there are 3 pairs capacitors under the power supply board. A pair capacitor for each channel and each pair shares the same power supply line.

This is one of the aspects that I will improve.

For my stereo listening, I only using 2 channel audio which are the channel 1 and 2 only. The power supply line will goes only go to those 2 channels individually without shares to others like when in multi-channel configuration. So, it is like a dual-mono amplifier design.

Then, the unused components such as relay protection circuit for channel 4, 5 and 6 will also delete. The clicking noise and small hum from relay inductor now become inaudible since now only 2 relays working instead of previously 6.

Again, why I doing this?

This is for 2 channel optimization and later, I can return all this modification to the original state whenever I want.







I make some changes in the potentiometer which I bypass it and prefer using external preamp or volume control rather using the built-in like this one.

This to make sure the potentiometer quality when using the external control is better.





This optimization makes this amplifier internal wiring simpler and tidier. Besides that, it also has the improvement on the noise level. It reduces the mechanical noise and performance noise.

The first things I really notice is the mechanical noise from the transformer and relays are now really quiet. It is common for EI transformer like this having the hum noise, especially when the size is huge like in this amplifier. Then now after the optimization, the hum is slightly quieter.

The noise performance in the music also reduced, creating more quiet noise background which you can feel the music deliver more detail and live. 

Once again, this Parasound amplifier is a good deal!

It intended not only for multi-channel audio for home-theatre, but it really sound wonderful in the stereo setup like this.


Disclaimer: Any statement and photos in this article are not allowed to copy or publish without written permission from the writer. Any injury or loss from following tips in this article is not under writer responsibility.

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