Topic: m-stage headphone amp

[raymonda]

Well, since I was so pleased with the Matrix mini i I decided to try their m-stage headphone amp. I went with the upgrade opamp BB627A. Total was 280. Been running it for a while and it seems to be a real nice value. Apparently it is a clone of the Lehmann black cube linear, of course made in China

Here are some specs:

Introduction
The M-stage is a fairly basic headphone amp. It features 2 sets of RCA inputs on the rear, which are selectable via a switch on the front panel. It also has a line out which enables the unit to be used as a pre-amp. Aside from the input selection switch, the front panel features a single 1/4” headphone jack and a volume control knob. A power switch is located on the rear, just next to the IEC power cable receptacle. It really is a very simple design. The only somewhat unique feature is the pair of gain selectors on the bottom. Users can easily switch from 0, 10, 18, or 20 dB of gain, independent for each channel, with the simple flip of a few dip switches.

Features
·         New 2010 version with upgraded power transformer and redesigned circuit

·         Powerful output that can drive high impedance headphones (up to 600 Ω)

·         High quality components including ALPS VR, Nichicon caps, OPA2134 Op-Amps, etc

·         2 sets of line inputs selectable on the front panel

·         Can be used as a pre-amp with the line output on the back panel

·         Gain selectors can set 0, 10, 18 and 20 dB gains

·         Solid build with aluminum faceplate and steel case

·         Fully dynamic and well balanced sound on a dead quiet background

Specifications
Output Power: 200 mW / 300 Ω, 400 mW / 60 Ω

Input Impedance: 47 kΩ

Output Impedance: Line out 60 Ω, headphone out 5 Ω

Frequency Response: 10 Hz (-0.3dB) - 35 KHz (-1 dB)

Signal / Noise Ratio: >95 dB @ 0 dB

Distortion: <0.001 % (6 mW / 300 Ω)

Anyway, I sold the Grado I had because this offers as good, if not better performance with more flexibility. This might even be a good line level pre-amp in a nice budget system. As it stands it is a very good HPA.

[raymonda]

At the moment this unit is working nicely. I've been unsing it with my wife's Grado 125's and it sounds very promising. my RS2's were sent off to Grado Labs due to an intermittant buzz in one of the drivers. it happened only once in a while and usually when listening to cello or acoustic piano and with certain notes. The unit should be burned in by he time they return and I'll know more about the amp. I'll aldo barrow a friends Senn 600 to try out.

I'll also give I a try as a pre-amp and report back.

[raymonda]

OK, so I got my RS2's back from Grado. What great service, $75.oo and they replaced the drivers with 2 matched pairs. Oh, and they sing beautifully, too. Anyway, I've been driving them with the M-stage and what can I say but this little headphone amp is a great match. Plenty of drive, extended and clean. Clean, e.g., no noise what so ever. This unit is a great deal and IMO tough to match at its price or for that matter 2-3 times more.

I just finished listening to Steely Dan "everything must go" on vinyl. My front end is a Well tempered RP with a Sound Smith modified Benz Glider through an AcousTech PH1 phonoamp (Southerland Designed) and it was rich and wonderful. While typing this I am listening to the final mix of Kenny Neal show from Homer and again it reveals details while making it a very enjoyable listen.

Again, try it, you'll like it!