When space is limited, or we simply want to cut the outboard budget a little, it's time to think about 500 series modules. The trickiest thing with this type of outboard gear is that you have to pay special attention to what you buy to avoid noise and make sure the power supplied is enough for the unit to work at full performance.
Obviously, in 19" racks everything has more room (I'm referring to their construction) and is probably better isolated. But the key point is that they usually have the transformers outside the rack itself, which keeps interference away. Secondly, the transformer is bigger and we don't have those power limitations.
At this point, once we decide to add a collection of 500 series outboard units, the first thing we'll need is a good rack frame. The unit that will let us plug in all the preamps, compressors, etc. in our rack.
We'll have to consider its power capacity (for all the units that will be connected), its construction materials (strength, looks, efficiency) and whether the products go through demanding quality tests, regardless of whether they are made in the USA, Europe, China, etc. Finally, we'll have to assess its functionality and connectivity.
The Fredenstein Bento 8 Pro
It features a complete linear power supply consisting of a mains transformer and linear regulators. This design delivers the cleanest power to the modules. Linear power supplies generally can't deliver high output currents. In this case its capacity is satisfactory.
The Bento provides 8 outputs of +/-16V DC 2A and +48V DC 0.25A, 500mA per slot. That's ample power for the most demanding 500 series modules!
Another drawback of linear supplies is that they tend to magnetically induce hum from the mains transformer directly into the input and output transformers inside the modules, especially when they are plugged into the slot closest to the supply. The Bento 8 Pro incorporates extensive magnetic shielding of the mains transformer to eliminate induced hum. It also has a monitoring section.
Headphone amplification and meters
The rack frame has a discrete stereo headphone amplifier, VU meters and independent slot output selection for the L and R channels. This means we can use a selector (one for each VU meter) to choose which unit in the rack frame we want it to meter.
To listen to a mono signal, we set both selectors to the same slot. The independent selectors give us total freedom to choose the source, and even allow us to reverse the stereo field by assigning the left channel to the right slot and vice versa. The left VU meter is connected to the selected L slot and the right meter to the selected R slot.
Also on the front panel we find three LEDs that show its operating status (+16V, -16V and +48V)
Construction materials
The Bento 8 Pro is built with quality components: 1.5 mm (59 mil) steel chassis, toroidal mains transformer with two built-in thermal fuses, Schottky diode rectification, all Nichicon electrolytic capacitors rated for 105°C (221°F), etc.
Built-in audio routing
The modules can be chained thanks to switches on the rear panel. We can also set up compressor bus links.
Compressor modules can also be linked via handy switches on the rear panel
Ground lift switch
There is also a switch for breaking ground loops. However, this option should only be used if strictly necessary.
Conclusions
We tested the unit with several 500 series modules (Neve, SSL, Heritage Audio). The result was really satisfactory in all our tests. Zero noise, no ground conflicts, good VU meter sensitivity and optimal operation of the units. Quick installation and everything working the first time without conflicts.
As for price, there are somewhat cheaper units. Although, at first glance, they can be a bit worrying in terms of noise and seem somewhat flimsier. In this case we're talking about around €450, although the brand offers the same product without VU meters for about €100 less. There are also similar products at considerably higher prices. Top brands that dispel any doubt about performance throughout every hour of use over the product's lifetime. However, after our tests, we can confirm that the Bento 8 Pro Pure Analog works without any problems.
We missed a front-panel switch to turn the power on and off from the front of the rack. Using a trick (additional gear), we managed to switch it on without having to plug and unplug it, but it would be a nice addition and doesn't seem hard to implement.
