No timepiece reaches the Case on appearance alone. Before a timepiece is offered, it is examined, authenticated, pressure-tested, demagnetized, and verified for chronometry, so that what you receive performs as beautifully as it looks.
The new standard
Every timepiece, on the record
Each timepiece offered by Tashan is thoroughly examined before it is catalogued for sale. Each is first authenticated in detail against the manufacturer's reference specifications. Each is then tested on state-of-the-art calibrated instruments for water resistance, magnetism, and accuracy. Each is tested at least twice, once on intake and again before it is shipped to you, to ensure its performance. The findings are recorded in a condition report, provided to you at the time of sale for your reference.
Step One
Authentication
Every detail, verified. Every reference, movement, and detail is verified against the manufacturer's specifications before a timepiece goes any further.
Step Two
Testing
Every function, measured. Once authenticated, each piece is measured on the Witschi WAIO for water resistance, magnetism, and accuracy.
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Step one · Authentication
Verified against the maker
Every reference, movement, and finishing detail is examined against the manufacturer's specifications. Anything that affects the integrity of the piece does not meet our standard and is not offered here.
House of Tashan traces the history of each timepiece as far as the record allows, gathering what can be learned from those who owned it before, so that its provenance passes to you together with the piece. A timepiece is more than the sum of its parts; where it has been is part of what you receive.
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Step two · Testing
Measured on the Witschi WAIO
Most timepieces change hands untested, sold on appearance and a word of assurance. At Tashan, every piece is measured before it is offered, and the results go with it.
For more than seventy years, Witschi has been the name watchmakers trust for testing, its Swiss instruments found on the benches of independent watchmakers, official service centres, and the manufactures themselves.
The WAIO, Witschi’s All-In-One, sits at the top of that line. Most testing tools do a single job, and most Witschi machines in daily use check timing alone; the WAIO measures water resistance, magnetism, and accuracy together, in one automated sequence, to the same standard the manufactures themselves hold. It does the work of an entire watchmaker’s bench. The House does not run it on its automatic setting. Each timepiece is programmed to its own specification, its beat rate, its lift angle, its depth rating, and measured against that standard. Three measures, recorded on every piece.
Water resistance
The case is sealed and put under pressure, from a vacuum up to five bar, while the WAIO reads how it flexes. The faintest leak shows as motion no eye could catch, measured against the timepiece's own depth rating. Water is the enemy of any movement; this is how we keep it out.
Magnetism
A phone, a laptop, even a handbag clasp can magnetize a movement without you knowing, and a magnetized timepiece runs fast. The WAIO measures the magnetism present, removes it, and shows the difference it made to the timing.
Accuracy
We measure how well the timepiece keeps time across four positions, the way it will really sit through your day, and report the deviation in seconds per day alongside the movement's health. You receive the true number, never a vague promise that it "runs well."
See for yourself
The test, start to finish
Video to come
Timepiece the full test
Every piece is filmed on the bench. Timepiece a full run, from pressure test to chronometry, exactly as it happens before a timepiece reaches the Case.
Your report
Every result, explained
Every piece leaves Tashan with its full condition report, yours to keep. Below is a real one, from a Glashutte Original Sixties Panorama Date. Each of the three tests reads the same way: on the left, what the result means in plain language; on the right, the exact figures the WAIO recorded and the graph behind them. These are the readings as the machine gave them.
Water resistance
Measured to depth.
Water is the greatest threat to any movement. To test the seal without ever risking the timepiece, the WAIO uses no water at all: it encloses the case, draws a vacuum, then raises the pressure to three bar, about thirty metres of depth, while measuring how much the case flexes. A leaking case gives itself away by deforming the wrong way. This one held steady through both stages, which means it is properly sealed, ready for rain, hand-washing, and everyday wear.
✓ Sealed
3 bar
Pressure held
2 of 2
Stages passed
−0.5 bar
Vacuum stage
Case deformation under pressure (µm)
What the graph indicatesThe case stayed sealed at 3 bar and held within tolerance through both test stages.
Magnetism
Invisible magnetism, measured and drawn back out.
Magnetism makes a timepiece run fast, and it can come from something as ordinary as a phone or a laptop. The WAIO measured the movement's rate, passed it through a decaying magnetic field to strip any magnetism away, then measured the rate again. The two readings moved by just 2.6 seconds a day, a small difference, which tells us little magnetism was present to begin with, and the timepiece left Tashan demagnetised and clean.
✓ Demagnetized
1.1 s/d
Rate before
3.7 s/d
Rate after
2.6 s/d
Difference
Rate, before and after (s/d)
What the graph indicatesThe rate measured 1.1 s/d before demagnetising and 3.7 s/d after, a difference of just 2.6 s/d.
Accuracy
How faithfully it keeps time, across four positions.
No mechanical timepiece is perfectly exact; what matters is how little it drifts, and how evenly it runs. The WAIO timed this movement in four positions, dial up, dial down, and on each side, because a timepiece keeps slightly different time depending on how it rests, and yours will pass through all of them on and off the wrist. It ran an average of just under five seconds a day, comfortably within chronometer standard. Two more readings confirm a healthy movement: a beat error of 0.1 ms means it ticks evenly, and a 291° amplitude means the balance wheel is swinging with strong, well-lubricated energy.
✓ Within spec
+4.9 s/d
Average rate
0.1 ms
Beat error
291°
Amplitude
Rate across four positions (s/d)CHCB6H12H
What the graph indicatesThe timepiece averaged +4.9 s/d across four positions, with a 0.1 ms beat error and 291° amplitude.
Every measurement is recorded to the cloud. You receive a live link to your timepiece's own results, an Excel export, and a short guide to reading them. How to read your WAIO results →
Owned with confidence
Every piece leaves the House proven
Testing is not a service you ask for. It is simply how Tashan works. What reaches the Case has already earned its place.
