Recent content by fluid

The same fastener can be used for both types of applications, in thin material the rubber compress behind the material, in a blind hole it expands outwards. They all rely on bolt torque being sufficient to hold. When using different torque amounts for different bolts, a simple mistake during...

I'm not sure why anyone would mount those another way in a speaker but someone probably has. Fail was a bad word as I didn't mean that the insert would pull out. Over time in drivers with significant excursion those type can work loose more easily due to how they cut into the MDF. Good quality...

Insert nuts are great, funnily enough though, of all the types available the version in your image are the worst kind for longevity in MDF. They separate the MDF into layers which can fail, at least that is my experience with them. The expensive EZ-LOK or cheap mass made types with a thread on...

Superglue works to harden up the threads and let the screws go in and out, I used it on one of my speakers where I knew the drivers would be in and out a few times through the build.

The only damage to Purifi's reputation would come from misunderstanding the measurements, jumping to conclusions and pointing fingers. I have cautioned against that very thing in the other thread more than once. Hopefully the rest of this post would only go to reinforce that message. To me...

Given all the noise in the Sointuva measurement thread some of the good information could easily be overlooked. The issue of mechanical resonances and mounting affects all drivers. In the X version of the Purifi Drivers there is a 380Hz basket resonance that is obvious in all measurements I have...

Try and keep some perspective on the magnitude of the issue just from the driver. In the test above the 380Hz peak was at -65dB relative to the fundamental, that is 0.05% distortion.

My concern with this for the eventual owner would be that the reduction of low order distortion could be perceptually irrelevant and the changing of the bass response and passive radiator response more relevant. Understandable but a shame as a few different tests might have helped draw a more...

I don't see what I said and you said as contradictory. A mode that is damped enough not to present as response issue in of itself does not suggest, that cannot couple into another mechanism and present as a different problem, which in this case is quite likely.

It is very easy to make a change, see a different measured result and interpret the cause of the difference incorrectly. It is obvious to me from the impedance response that too much stuffing was put into the cabinet, as it had a negative impact on the bass tuning. Whilst this had a positive...

You are welcome, the information you have shared is great so I'm trying to help you interpret it. There is for sure more than one issue apparent in your original measurements. The resonance relating directly to the Purifi driver is present in both but is worse in one. The significant...

You are welcome :) Just to round it out here is a distortion graph from Hificompass at two different SPL's you can see that at the lower one there is a peak of 3rd Harmonic at 380Hz and then at 100dB there is a slight peak of 5th Harmonic at about 420Hz...

Not usually, but most drivers do not have the motor force, excursion and generally low distortion to make the effect so obvious. I did edit the post above to add another reason but on checking they measured at 2.83V which does produce an SPL of about 86dB.

Most likely because they isolated the driver from the baffle with damping or mounted it via the magnet, or they measured it at an SPL level where the resonance wasn't excited.

Sure but sometimes smart people don't imagine that an obvious problem to them isn't so to everyone. Why GPS devices no longer tell you to make an immediate U turn. I think you misundertand, grounding in this context doesn't mean electrically, it means allowing the reaction forces to be...