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Dangerous Music Source
Monitor Controller and Headphone Amp
Made in USA
© 2015 KenRockwell.com. All rights reserved.

Intro   Specifications   Measurements   Usage   Recommendations

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Dangerous Music Source

Dangerous Music Source. enlarge. (1.625" x 12.75" x 8"/41 x 324 x 203 mm HWD, 5.5 lbs./2.5 kg, about $900 each).

 

Dangerous Music Source

Rear, Dangerous Music Source. enlarge.

I got mine at B&H as part of a kit with my Neumann KH 120A. I'd also get it at Amazon.

This ad-free website's biggest source of support is when you use those or any of these links to approved sources when you get anything, regardless of the country in which you live. It helps me keep adding to this free website when you get anything through these links — but I receive nothing for my efforts if you take the chance of buying elsewhere. Thanks for your support! Ken.

 

March 2015   Audio Reviews   All Reviews


Introduction         top

Intro   Specifications   Measurements   Usage   Recommendations

Adorama pays top dollar for your used gear.

B&H Photo - Video - Pro Audio

The Dangerous Music Source is a handy-dandy monitor controller and headphone amplifier for home studios.

Pop it on your desk, plug in your computer and some analog and digital sources, and it makes it fast and easy to select inputs and levels to run your speakers and your headphones. Plug-and-play, the way it should be.

It's very easy to use: tap a button to select a source, and it lights up. There are different colors for different things.

The headphone and speaker controls are completely separate. Each has 4 lit push buttons to select among the same four inputs: A1 (3.5mm -10 dBu analog), A2 (balanced XLR & ¼" combo), AES/SPDIF (balanced XLR & ¼" combo) and USB.

Each output has its own volume knob. They track well enough, and poke out enough and are well marked to make them easy to use. They are regular analog pots; so they respond instantly as you turn them. They turn smoothly; there are no clickstops.

Just tap your desired input and it plays. Read the User's Manual to see how to set it up so you can play more than one source at a time through the same output.

Each of 2 speaker outputs has its own lit pushbutton. You can use the second output to feed your subwoofers, for instance.

There's a rack mount kit available, and otherwise it's a 3/4-rack wide metal box with nice rubber feet that sits on your desk with a wall-wart power supply.

The built-in DAC and speaker controller is pretty good, but the headphone amplifier is only fair with low-impedance headphones. Use high impedance headphones for the best results.

 

Specifications         top

Intro   Specifications   Measurements   Usage   Recommendations

It's all in Dangerous Music Source User's Manual.

 

Measurements         top

Intro   Specifications   Measurements   Usage   Recommendations

I used a state-of-the-art Rohde &Schwarz UPL for these measurements.

Unless otherwise mentioned, these are from AES IN at 1 kHz at 0 dBFS and loaded with the 200k Ω load of the Rohde &Schwarz UPL.

The traces are color coded for the Left Channel and for the Right Channel. When they don't lie on top of each other, it's due to channel imbalance.

 

Headphone Output        top

The headphone amplifier is good enough for high-impedance headphones, with plenty of level (4 V RMS) to drive them.

It's poor for low impedance headphones. While they'll work OK, even an iPhone 6 Plus has more output at lower distortion for low-impedance headphones than this headphone amplifier!

Regardless of your choice of headphones, it has slightly weak deep bass response and more bass distortion than it should. Careful listeners may hear the lack of bass response, but headphones still usually have more bass distortion than this headphone amp.

 

Headphone Output Frequency Response

Dangerous Music Source

Headphone Frequency Response, Dangerous Music Source.

Dangerous Music Source

Headphone Infrasonic Frequency Response, Dangerous Music Source.

It is down 1.5 dB at 20 Hz, not really acceptable for serious use. This means the deepest bass is just a tiny bit weak.

 

Headphone Output Source Impedance

2.2 Ω.

This is excellent, and means that all headphones will have accurate frequency response that won't vary.

 

Maximum Headphone Output Levels

Level control at 4 o'clock at 0 dBFS or at maximum at -1.21 dBFS:

4.154 VRMS measured at 0.1% THD, 200 kΩ load.

4.138 VRMS measured at 0.1% THD, 600 Ω load.

4.122 VRMS measured at 0.1% THD, 300 Ω load.

This is a lot of output for high impedance (studio) headphones.

 

The headphone amp is not happy driving low impedance (portable) headphones.

It only puts out 0.269 VRMS at 0.1% THD, into a 37.5 Ω load (Level control at 10 o'clock). It will put out more voltage still with THD below 1%, but the output has more distortion than it should with low-impedance headphones. In fact, an iPhone 6 Plus has more output at lower distortion for low-impedance headphones!

 

Headphone Output Left/Right Channel Tracking

This measures how well the left and right channels stay balanced as we turn the volume control.

Dangerous Music Source

Headphone Output Channel Tracking.

Channel tracking is OK for general use, but not great for careful monitoring. You can hear when the channels are a dB off; so watch out. Every sample will be different.

Again, an iPhone is perfect here since it uses an electronic volume control, while the analog pot in the Source varies more than it should.

 

Headphone Output Noise

-100 dBV A at minimum, -99.5 dBV at 12 o'clock and -93.8 dBV at maximum.

This is super quiet, no problems here.

 

Headphone Output THD

Dangerous Music Source

Headphone Output THD at 1 volt, 200 kΩ load.

It probably won't be audible, but there should not be this much bass distortion

 

Dangerous Music Source

Headphone Output THD at 1 volt, 300 Ω load.

This is the same as at 200 kΩ, with more midband THD that's still negligible.

 

Dangerous Music Source

Headphone Output THD at 1 kHz, 37.5 Ω load.

This is sloppy. There is more distortion than there should be; an iPhone is much better at this.

 

Speaker Outputs      measurements    top

The speaker outputs are much better than the headphone outputs.

 

Speaker Output Frequency Response

Dangerous Music Source

Speaker Frequency Response, Dangerous Music Source.

Swell, much better then the headphone output - but look out for the 0.35 dB channel mismatch.

 

Dangerous Music Source

Speaker Infrasonic Frequency Response, Dangerous Music Source.

Perfect, except for channel imbalance.

 

Speaker Output Source Impedance

53 Ω.

Swell, you can run 300 feet of cable to your monitors and all is well.

 

Speaker Maximum Output Levels (measured balanced)

4.9 VRMS at 0.001 % THD at maximum gain at 0 dBFS, 200 kΩ load..

4.5 VRMS at 0.015 % THD at maximum gain at 0 dBFS, 600 Ω load..

4.16 VRMS at 0.045 % THD at maximum gain at 0 dBFS, 300 Ω load.

This is more than enough to fry any active monitor or power amplifier, so all is well.

 

Speaker Output Left/Right Channel Tracking

This measures how well the left and right channels stay balanced as we turn the volume control.

Dangerous Music Source

Speaker Output Channel Tracking.

Channel tracking is OK, but not great. This is tighter than the headphone control, and since it's for speakers, should be just fine. Each sample will be different.

 

Speaker Output Noise

-103.3 dBV A at minimum, -102.8 dBV at 12 o'clock and -94.5 dBV at maximum.

Again, this is swell.

 

Speaker Output THD

Dangerous Music Source

Speaker Output THD versus digital input level in FS, MAX level and 200 kΩ load.

This is testing the DAC more than the speaker output, and this is fine. 0.05% THD at -60 dBFS is swell.

 

Dangerous Music Source

Speaker Output THD at 0 dBFS, MAX level, 200 kΩ load.

Swell.

 

Dangerous Music Source

Speaker Output THD at 0 dBFS, MAX level, 200 kΩ load.

Excellent, even less than full-scale.

 

Dangerous Music Source

Speaker Output THD at 0 dBFS, MAX level, 200 kΩ load.

Swell, this is at -40 dBFS and still about 20 dB below audibility.

 

Total Power Consumption      measurements    top

8.5 watts drawn from the wall, measured.

 

Usage         top

Intro   Specifications   Measurements   Usage   Recommendations

It's all in Dangerous Music Source User's Manual.

 

Recommendations         top

Intro   Specifications   Measurements   Usage   Recommendations

This is a very handy desktop headphone amp and monitor controller. It's super easy to use all day.

Its technical performance is good for the DAC and speaker controller and for high-impedance (studio) headphones, but sloppy for low impedance (portable) headphones.

It's an American-made product, and I was impressed at how super-clean it was when I unwrapped it.

I got mine at B&H as part of a kit with my Neumann KH 120A. I'd also get it at Amazon.

Personally I prefer my Benchmark DAC1 HDR, which doesn't have quite as much flexibility, but has far better performance and mechanical quality, also made in USA. I don't recommend this Source unless it just happens to fit your particular needs, while I highly recommend the DAC 1 HDR, which is a genuinely professional product compared to the home-studio grade Source.

This ad-free website's biggest source of support is when you use those or any of these links to approved sources when you get anything, regardless of the country in which you live. It helps me keep adding to this free website when you get anything through these links — but I receive nothing for my efforts if you take the chance of buying elsewhere.

Thanks for your support!

Ken.

 

Help me help you         top

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Mr. & Mrs. Ken Rockwell, Ryan and Katie.

 

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28 March 2015