Topping Pre90 preamp with Ext90 expansion module: step volume control and 0.00007% distortion

The Chinese company Topping has released a pre90 preamp, supplemented by an Ext90 input expander. Two cases of the new product are “half” wide, that is, together they have a completely “rack” size.

The Pre90 preamp features just one RCA stereo input and one XLR. But when it is supplemented with an Ext90 expansion module (and connected to it with a special cable), two more RCA and four XLR stereo inputs are added to them.

You can remember the gain level for each input in the system to equalize the volume of all connected sources. The output signal can be output to either the balanced or unbalanced connectors, or both at once. This allows you to use two switchable options for end amplifiers and speakers.

The volume in the range of 145 dB in 0.5 dB increments in the system is regulated by a step switch on the relay. The device is equipped with a turn-off safe volume function, when the signal is too large when turned on, it automatically decreases to save your hearing.

The Pre90 preamp is built on NFCA (composite amplifier with nested feedback) modules from the flagship A90 model. The fully balanced circuit uses a hybrid voltage and current feedback architecture along with UHGF (Ultra High Gain Feedback) technology. The result-at a frequency of 1 kHz, the novelty demonstrates a signal-to-noise ratio of 124 dB and a CNI of 0.00007%.

All Pre90 functions are available from the standard remote control, and information about the operating mode is visible on the text display. Both Pre90 and Ext90 modules are available in black or silver finishes. The cost of the kit in the United States was $850.