Pro-Ject Phono Box MM, Phono preamplifier with metal case and special low-noise ICs

Product Information

The moving magnet preamp delivers a high-end output of around five millivolts. As such, it requires far less gain and it also costs a lot less. The sound quality is inferior, however. This is where the phono stage (or phono preamp) comes in. It has two jobs. Firstly, it has the reverse response built into it – one that boosts bass and flattens treble to exactly the right degree, which should result in a tonally even presentation for the audio signal. Many new record players, such as the Audio Technica AT-LP120, come with a built-in preamp. But not all self-contained turntables do. All adjustments can be made "on the fly" via the front panel—no tiny DIP switches or optional loading resistors—which encourages experimentation. As you'll see, I experimented plenty. I used 680nF (0.68µF) input and output caps, because I had run out of 1µF 63V units - 1µF/100V MKT caps are too big to fit in the space allowed. Even so, low frequency response is perfectly acceptable as indicated above. A -3dB frequency of 2.3Hz is adequate for all normal listening pursuits . If preferred, you can use a 10µF electrolytic, which can be polarised or bipolar. There's no DC voltage to speak of, and even polarised electros will have a long and happy life.

Like the larger units, this junior model delivers up to 70dB of 1073-style microphone preamplification, while doing away with features that some users might not need. The first thing we noticed, apart from its unusual proportions, is the simplified input gain rotary switch. Whereas the other models feature the unique 1073-style Mic/Line switching arrangement, the Junior offers mic gain only in 5dB steps from 20 to 70dB. A continuously variable Output control pot is provided, along with an instrument DI input. Operating the second stage with no gain is not recommended. It may oscillate due to the extraordinarily wide bandwidth of the opamps used, and the comparatively high capacitance at the inverting input. Having said that, it's only a few pF, and when operated with any gain there's little chance of instability. 0dB gain for the second stage is unlikely to be a requirement in practice. If your turntable doesn’t have a built-in phono stage, you’ll need to connect it to a dedicated phono input input on your amp. If you were to plug your turntable directly into the same place, skipping the phono stage, any sound produced would be very reedy, very thin and stupidly quiet. Two new CD players come from Pro-Ject: the larger "CD Box DS3" and the more compact "CD Box S3". Both carry analog as well as digital outputs. Because we are always asked how to connect the equalization preamplifier or phono preamplifier, we would like to write a little guide.The analog output is a buffer that is both solid state and high-quality tube. Thus, the customer can choose which of the option is preferred. The Pre Box has eight digital filters. One of them is the proprietary optimal transient digital filter from the MQA creators. With these filters, the listener can customize the sound to suit their own preferences. Pre Box RS2 Digital comes with full HW and SW support for MQA technology (Master Quality Authenticated). Yes, there is also this possibility. You can buy a turntable with an integrated preamp. However, this decision only makes sense in a few cases. For example, if you only want to listen to a record occasionally or digitize old records, a turntable with a preamplifier can be a good idea. After all, this can then be easily connected to an amplifier and used directly, this also applies to the PC or the sound card. If you want to listen to a turntable for music and also the appropriate quality, then a turntable without an integrated preamplifier is the better choice. In this way, you have significantly more control over the individual components of your system and can easily retrofit or replace as required. Information About The Test And The Product Recommendations Whether it is a phono stage or an external preamp, it boosts the signal from the turntable to the correct level, so that it can be received by your stereo system or speakers. The Pre Box RS2 Digital has an I 2S-capable HDMI input specifically intended for use with the CD Box RS2T. Pro-Ject describes I 2S as “the perfect digital interconnect and ... the ideal solution to bypass the limitations that inherently come with other forms of digital audio connections.” For music lovers who still spin shiny discs, the Pre Box RS2 Digital and CD Box RS2T form a compelling combination. Earlier boards included RF interference suppression by adding a small capacitor between the two inputs of U1 (the space for this cap can be seen in the PCB photo, which is of an early board). This has now been removed, as it caused more problems than it solved - in particular, opamp oscillation with some devices.

The headphone amplifier is the ultimate design. No compromise. No coupling capacitors. Not even on the output. All of the the amplifier is DC coupled. A very fast DC servo assures no DC voltage on the output. Its output power is suitable for all kind of headphones.SME at its best – Wow! This looks fantastic! As a successor to the Model 10, the English analog specialist SME presents the new Model 12 turntable, which will not only appeal to vinyl fans with its attractive shape.