The first unit is built
The plan was to build the first two pre-production TENSA mixers, and the first one is done. It is fully assembled — enclosure, PCB, tubes and wooden cheeks — and it works. The second unit is next in line.
What the first build showed
The board needed very few changes. Two resistors in one channel had to be changed in the schematic: we did it on one channel and simply forgot on the other — our mistake — so after the factory we swapped them by hand. Two more resistors went into the VU meter circuit to adjust the meters' sensitivity. That is the full list for the main board; the power supply only needed minor fixes, a resistor replacement.
We did find one real issue. When the phono stage on one channel is switched on or off, you sometimes hear a couple of clicks while the tubes warm up, and then they go away. The cause is the heater supply: switch off the second phono stage while the first one is running, and the heater voltage rises slightly — that is the moment of the click. It should not happen, and it will be fixed. That is the only problem we have run into; everything else is great.
The faders are something we want to upgrade. The current ones are fairly narrow — the same kind you find in Pioneer and Allen & Heath mixers — and we don't like them. There are wider faders with a wider base inside: they are rated for 30,000 cycles instead of 15,000, have no play and feel noticeably better made.
What's next
The cheeks of the first unit were made by hand from solid olive wood. Next we want to try other woods too, and most likely cut the cheeks on a CNC machine for maximum precision. Meanwhile we are building the second unit, and in the coming days we are taking the mixer to Barcelona to present it and talk to shops there about working together. From here on, we are going to show TENSA to many more people.
Pre-orders are open
The pre-order form is now live on the site, so if you want a mixer, you can reserve one right now. The first batch is only 20 units, and many of them will go to promotion — if there is a lot of interest, there may not be enough for everyone. With every buyer we agree individually on the knobs and the colour of the wood.