Comparison Scansonic USB100 vs Dual DTJ 301.1

The signal level at the output of the pickup supplied with the player is, in fact, the power of the signal coming from the pickup to the phono stage. This parameter is necessary, first of all, in cases where the player is planned to be connected to an external phono stage: such equipment must be designed for the corresponding power of the signal coming from the pickup.

The effective length of a tonearm in set is the distance from the attachment point (axis of rotation) to the stylus.

This indicator is important primarily for rotary tonearms: the longer the length, the lower the angular error, the smaller the discrepancy between the direction of movement of the track and the longitudinal axis of the pickup (for more details, see “Type”) and the lower the level of corresponding distortion. In addition, a longer length reduces the resonant frequency and reduces the likelihood of distortion. On the other hand, a longer tonearm turns out to be heavier, which requires certain technical tricks and can also negatively affect the purity of the sound. Therefore, a large length is not always a guarantee of high quality – you should also pay attention to weight (see below).

A method of transmitting rotation from an electric motor to a record player rim.

— Belt. Also known as "belt". As the name suggests, this type of drive uses a belt transmission. Its main advantages are uniform rotation combined with undemanding quality of electric motors, which allows achieving good sound purity even with relatively simple and inexpensive motors. True, belt players pick up speed more slowly and are unsuitable for special techniques like scratching; however, these points are critical only for DJs, and do not have much significance for ordinary music listening. But among the clear disadvantages, one can only note the need for periodic (usually once every few years) replacement of the belt.

— Direct. In players with this type of drive, the disc is mounted directly on the electric motor shaft. This allows it to accelerate and brake very quickly, as well as use various special techniques, due to which a direct drive is almost mandatory for a DJ turntable. However, such a design puts forward special requirements for the quality of electric motors, since any unevenness and vibrations significantly affect the sound quality. Therefore, in "audiophile" models, a direct drive is rarely used - in the absence of obvious advantages over a belt drive, the design turns out to be noticeably more expensive.

A phono corrector is a specially designed preamplifier used when working with vinyl record pickups. Initially, the sound on such records is recorded with distortion of the amplitude-frequency characteristic, namely with an increase in volume from low to high frequencies; this is due to the technical features of the recording process. Accordingly, the phono corrector not only amplifies the signal to a level sufficient for feeding to the power amplifier, but also corrects the amplitude-frequency characteristic, “pulling out” the bass and reducing the volume of the HF. And the built-in phono corrector allows you to connect the player to the power amplifier directly, without using intermediate equipment. True, in terms of characteristics, built-in preamplifiers-correctors are inferior to external ones. Therefore, some models with this function may provide a “bypass” mode, allowing you to pass the signal bypassing the built-in phono corrector to an external, more advanced one. And there are also vinyl players without a phono corrector at all.

The sampling rate of the A/D converter installed in the player. To listen to vinyl in the usual way (cartridge — phono stage — power amplifier — acoustics), it is not necessary to convert the analogue signal coming from the pickup into digital format. This function (and, accordingly, the characteristics of the ADC) is relevant only when recording to a computer or removable media, as well as when using a digital audio output (see "Characteristics").

When digitized, analogue audio is decomposed into separate "pieces" (samples), and the data for each sample is recorded digitally. The sample rate describes how many samples there are for every second of the audio being converted; the higher it is (ceteris paribus), the closer the digital audio signal will be to the original. The most modest converters in modern turntables are capable of operating at a sampling rate of 44 (more precisely, 44.1) kHz — the quality of such a recording corresponds to an Audio CD and can already be indistinguishable from high-end vinyl. And in the most advanced, this figure reaches 48 kHz (DVD and DAT level).

The bit depth of the analogue-to-digital converter installed in the player. To listen to vinyl in the usual way (cartridge — phono stage — power amplifier — acoustics), it is not necessary to convert the analogue signal coming from the pickup into digital format. This function (and, accordingly, the characteristics of the ADC) is relevant only when recording to a computer or removable media, as well as when using a digital audio output (see "Characteristics").

When digitizing an analogue signal, it is decomposed into samples (for details, see "ADC Sampling Frequency"), and for each sample, its own signal level value is indicated. The higher the ADC bit depth, the more accurately this value will correspond to the initial signal level and the closer the digital sound will be to the original. To digitize audio as an Audio CD (which is already considered quite “audiophile”), 16 bits is enough, but in modern players this figure can be even higher — up to 24 bits.

The ratio between the useful signal and extraneous noise at the output of the player. It is also colloquially called "electrical noise" (although this is not entirely true).

The higher this indicator, the quieter the noise (it is impossible to completely eliminate them), the clearer the signal will be. In the case of turntables, the signal-to-noise ratio is considered to be at least 50 dB; and in the most high-end devices it can exceed 90 dB.

Note that this paragraph may additionally indicate the value of mechanical noise. Despite the similarity in name, this is a completely different indicator — it describes the volume of extraneous sounds produced by the motor, drive and other moving parts of the "turntable". Accordingly, for mechanical noise, the lower the decibels, the better. You can estimate its approximate level using special comparative tables.

The maximum knock factor that the turntable is subject to under normal conditions.

Detonation in this case is called sound distortion associated with short-term periodic irregularities in the rotation of the disk. The lower the detonation coefficient, the lower the level of such distortions; it is believed that for audiophile-class equipment it should not exceed 0.2%, although in more modest models it may be higher.

Note that for different playback speeds, knock coefficients can also be different. Manufacturers in such cases may indicate the minimum value, despite the fact that it can be achieved not at the usual 33 rpm, but at 45 or even 78 rpm. Therefore, when choosing a high-end turntable, it's ok to clarify this point.

Rated power consumed by the player during normal operation.

Modern turntables are very economical: most models, even those equipped with built-in acoustics (see "Features"), the power consumption does not exceed 15 W, and there is no need to talk about any serious impact on congestion in the electrical networks (as well as electricity bills). The exception is some premium-class devices, in which the weight of the platter (see below) reaches several tens of kilograms, and the corresponding engine power is required to rotate such a mass.