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The NSL is a 28 watt per channel, stereo, solid state, almost Class B, very low distortion, power amplifier.


We spelled out the 28 watt per channel and the almost Class B business just to get the audiophile non-approved stuff out of the way early.  Now, down to business. If you have an open mind and have managed to read past the first sentence, you can read on to see why we are  offering this amp at this price.


It's all about the sound or, if you prefer, the music.  Music is just sound.  In order to reproduce good music, we have to make sure it sounds right. That means accuracy and accuracy is, in great part, a result of low distortion. Low distortion to us means more detailed information can pass through without any alteration.  Almost Class B means we just bias it just enough to
get rid of the unwanted stuff but keep it running very cool.  

Redefining Powerful:

The NSL has a measured output of 28 watts into 8 ohms and 56 watts into 4 ohms per channel.  Not impressive? Well, it also has an output impedance lower than most 300 watt power amplifiers.   Instead of using a few big transistors like most common designs, we parallel 288 op amps at the output stage.  This is like using multiple smaller capacitors in the power supply instead of one big capacitor to obtain faster and smoother response. In power output stage terms, it can get the output impedance lower than ever before. This yields much better control of the speaker drivers and as a result this amp sounds more powerful than power amps with many times the output wattage of the NSL.  The NSL demonstrates measured output numbers don't necessarily determine how it sounds.

Very Low Noise:

With the parallel op-amps, it has less noise than headphone amps.  The residue noise is very low within the waveforms human hearing interprets as comfortable sound.  With the lower noise floor more musical details come through without the distraction of the noise.

Battery Operation:

Many line level components offer battery operation.  Some of our preamps use supercaps instead of batteries with the same goal in mind. They can run for hours without ac power.  AC powerlines have all kinds of noise which is impossible to totally filter or eliminate.  Totally off the grid is the only way to avoid any powerline noise.  
It’s easy to make line level components work with batteries. Power amps are a different
matter.  Since power amps draw a lot of power and batteries usually only come in 12V form, there are a lot of things to do in order to make an amplifier run on batteries and most battery operated power amps don't have a lot of wattage Those that do run for only short periods of time before requiring a recharge.  The NSL has dealt with both issues.  The NSL is can run on batteries.  With two 115Ah 12V deep cycle batteries, it will run up to 24 hours with one charge.  


The output stage of the NSL is a modular design, more output modules can be added to increase power output.  It is possible to have the NSL output increased to over 500 watts into 0.5 ohms.


If you’ve been here before you know don't talk about the sound because we would rather have people who have heard this amp talk about it.  What we can tell you is if it didn't sound good, we wouldn't be telling you about it and we sure wouldn’t be producing it.

Technical specs.:

   -Output:  28 watts into 8 ohms and 42 watts into 4 ohms per channel.
   -True balanced from input to output with both positive and negative binding posts being "hot with signal.
   -DC coupled from input to output.
   -Local "on board" filtering capacitors located less than an inch away from the actual output devices for better transient .....response.
   -600VA power transformer supply for output stage only.
   -Over 2,000,000uF (2.0 Farad) in power supply filtering.
   -14Ga steel chassis for mechanical integrity.
   -1" thick MDF base tightly coupled to the bottom of the chassis for ultra rigid damping control.
   -Various colours of faceplate, base and cover as options.
   -Two pairs of binding posts per channel for shot gun biwire.
   -RCA and XLR inputs.
   -Battery connection jacks for external battery module(s).
   -Output module expandable jacks to connect additional output stages.
  -Ground lift switch to eliminate ground loops. This switch will only lift the signal ground, the chassis is connected to earth ground ....at all times for safety.
   -Dimensions: 20.5" wide x 9" high x 21.5" deep.
   -Weight: 65lbs.

Optional features:

   -Battery module for off the gird operation.
   -Output modules for increased power output
   -Rails voltage meter to monitor battery life


   -Residue noise reference to full power output: >-106dB or <75uV non weighted
   -Residue noise reference to full power output: >-113dB or < 30uV within audio band
   -Tracking error: < +/- 0.09dB
   -Frequency response (10W into 8 ohms): 5Hz to 50K +0.00db, -0.05dB; -0.9db point at >100kHz
   -Distortion at 10W into 8 ohms: <0.05%
   -Voltage gain: 26.0dB
   -Input sensitivity: 0.75V
   -Input impedance: 6.3K (SE); 12.6K (BAL)
* all measurements taken with balanced inputs.

For lots more photos of the NSL  click here.
Contact:  bcircle@bluecircle.com  /  519-469-3215