I returned to DIY electronics in 2009 after a 20 year pause by building a few kits to get in shape. This blog is for me to keep track of my progress.
NE5532 power amplifier
Posted 12th May 2013 at 07:51 PM by alexcp
This is a project developed by Douglas Self and published in the Elektor in October and November 2010.
The idea is rather unusual: "An interesting power amplifier can be made by connecting enough 5532s in parallel, how about 32 for a start? This may sound like a radical course of action, but it actually works very well, making it possible to build a very simple amplifier that retains not only the excellent linearity but also the power-supply rejection and the inbuilt overload protection of the 5532, which reduces the external circuitry required to a minimum."
Elektor used to sell PCBs for this project, which I used. I modified the circuit slightly to incorporate an active volume control along the lines of Douglas Self's preamplifiers.
Here is the result:
The idea is rather unusual: "An interesting power amplifier can be made by connecting enough 5532s in parallel, how about 32 for a start? This may sound like a radical course of action, but it actually works very well, making it possible to build a very simple amplifier that retains not only the excellent linearity but also the power-supply rejection and the inbuilt overload protection of the 5532, which reduces the external circuitry required to a minimum."
Elektor used to sell PCBs for this project, which I used. I modified the circuit slightly to incorporate an active volume control along the lines of Douglas Self's preamplifiers.
Here is the result:
Total Comments 2
Comments
-
How does it sound Alex? Always wondered how this kind of amp would sound and its also similar to beast with a thousand jfets which I'll never be able to build so this would be next best thing I guess.Posted 1st November 2013 at 02:41 PM by udailey
-
That is the most difficult question
it is completely subjective, of course, so you may or may not feel the same even listening to the same specimen. You've been warned 
My test setup consists of an Exposure 2010S CD player with a TentLabs XO 2.2 low jitter clock upgrade, the OpAmplifier per se and a pair of Klipsch Heresy III three-way speakers on low 18" stands in the corners of a small room with non-reverberating stuff along the walls. The SPL at my listening position is 75-80dB.
To my ears, the OpAmplifier sounds like a reasonable class B amp. It is dead quiet, the sound is clean and transparent. There is a hint of excessive sibilance, but it is not conspicuous.
When listening to The Very Best of Placido Domingo, published by EMI Classics, which is my acid test for amplifiers, the amp gets stressed on higher notes and gives the tenor's voice some coloration, but then this happens in my setup, and with this music, to every non-class-A amplifier.
Buena Vista Social Club, on the other hand, is rather enjoyable if a little sterile; the guitars could use some warm and relaxed sound often associated with SE amps, which OpAmplifier lacks.
Overall, it is not a bad amplifier, but it is not as exciting as my Balanced Burning Amp 3 or my Zen V4 with power JFETs. OpAmplifier does not give me the toe-tapping experience that I am after. I think it is more an experiment in building an unusual amplifier than an amplifier of ultimate fidelity.
Remember, this is subjective; your impression may vary.
Hope this helps.Posted 2nd November 2013 at 08:46 AM by alexcp
Updated 11th November 2013 at 12:29 PM by alexcp
