Product Testing and Evaluation
Below are some pictures of Product Testing and Evaluation in action. This process is the final stage of any project and it very important. My engineer runs all products through a rigorous set of checks before anything goes out the door. Evan is very thorough.
This is the very first set of speaker cabinets that I built. Evan is pretty pleased with the overall quality. Evan uses the wire strippers to ensure that all connections are proper.
Here Evan checks the binding posts to ensure that they are properly fastened and solid. These are pretty good. Evan notes that these type of binding posts are vulnerable to shipping damage, and should be removed before shipping.
Here we see movement from the binding posts to the outboard crossover. Every movement is careful and deliberate.
Evan expresses his opinion about the drilled binding posts. He states that the drilled individual posts are much easier to access than the plate mounted type. It is unfortunate that these posts are more susceptible to shipping damage.
Ah, the crossover! This is the most important part of any speaker. Evan notes that this one is outboard so it is much easier to access. Theoretically, less vibration should yield less capacitor noise, but we can't hear any audible difference. The crossover is also where the builder spends a great deal of time. All the connections are crimped solid using a dedicated crimping tool. Wherever possible there are several wires entering the same terminal barrel and crimped firmly together. Cardas solder is then added to seal the joint and complete the contact gaps. This is the best type of wire joint.
Here are some pictures of Evan using LspLab. This is pretty fun, but not like the wood shop. Evan and dad love power tools and always wear hearing protection. See below for more details.
The keen eye will notice that Evan is checking the leads for an Ohmite Resistor. We did some listening tests with Mills/Ohmite/Eagle. We didn't hear any difference, but we did this test with Solen Capacitors in series too. The Solen's are quite harsh. Now that Evan and Dad are using the Rel-Cap capacitors, we should probably do some resistor comparisons again.
Evan points out that we could put the W18 in a 30 liter floor standing cabinet and get more bass extension. This is true, but the baffle step might not be the same. We need to check this using Paul V's diffraction program before attempting a 30 liter cabinet.
Breakfast is the most important meal of the day. It is essential for good problem solving, and oxygen uptake. The dark smudge around the mouth and smile indicate that Evan is quite happy that dad shared some of his breakfast. This consisted of bread, eggs, milk, and flour (Chocolate Cake). Mmmmmm!
Hands on quality evaluation is a necessary for obtaining accurate results. Evan approves of the oak stringers used on this crate panel. Oak holds screws better than fir and will be more durable in the long run. This crate must survive many UPS "caregivers". These "caregivers" easily find ways to finesse packages, but this crate will do fine. Evan believes the glue used in the stringers is overkill, but acknowledges the overall superiority of the glue joint.
Evan and Dad always wear hearing protection when using power tools!
This past weekend a tragedy occurred. Dad's trusty old table saw died. We tried to resurrect the motor on Tuesday, but our efforts were in vein. It's passing is a grievous loss. Evan and Dad have spent a plethora of quality time with that saw. It was a venerable old saw - a Sears & Roebuck. It was made abut 35 years ago when craftsman made good power tools. We will be getting a new saw, but this will take a few weeks. Choosing the right saw is kinda' like choosing the right spouse. The decision is almost eternal. This next saw will be a Powermatic. It will have a much better fence, more power, and should last even longer. We will have it in a few weeks.
18 Feb 02: Evan is 18 months old. Today Evan used the Porter Cable RO sander. He was spending some time in the shop today while Dad sanded some Cherry with his Porter Cable 7336 RO sander. Evan keenly remembered that Dad has another RO sander. Evan urged Dad to pull it off the shelf. Upon doing so Evan put the sander on the cherry and started making a humming noise.
Dad turned the sander "on" and Evan used the sander - just like Dad.
Dad offered to help Evan a few times, but Evan gently pushed Dad's hand aside as if to say "I can to this Dad". It was a precious moment.... Hmmmm, if only we could get him to stop throwing food at the dinner table.
Evan inspects the quality of parts received in the mail. This particular capacitor is an AudioCap Theta. It is both larger and heavier than other capacitors. This is due to the copper foil within the Theta and the very solid construction. Evan is keen to cite that bigger and heavier doesn't always indicate quality, but in this case it does. The proof is in the hearing. This capacitor doesn't generate any noise and all of the detail gets through..