09-11-2015, 09:55 AM
(This post was last modified: 09-11-2015, 09:55 AM by DocWils.)
I am testing the Z1 auto to see if it will be taken into the offerings here, but the device came without the new muffler system (and a GE passive humidifier sponge rather than HDM's own type).
It sounds like a buzz saw revving up and down with each breath, or more like a dentist's drill, really - very high pitched and extremely loud, even with a 22 cm hose and hose covers. Does anyone who has the muffler know if that takes away that sound at all? I want to give the device a fair assessment, but without knowledge that the muffler really makes a major difference, I will not recommend it for use here.
I am getting the muffler for my Z1 today I will let you know how it works.
Dentist's drill. Ha!
Don't have the muffler. Shouldn't need a separate muffler. It should be made into the adapter on the end of the hose where it meets up with the machine.
Well, I gave up on my unmuffled Z1 after around 30 minutes - it was far too loud to let me sleep (and I'm a DOCTOR! I'm used to sleeping in closets on noisy hospital floors between shifts! The last thing I want to hear as I'm trying to sleep is a noise I hear as a surgeon every day - the whine of the surgical saw). She Who Must Be Obeyed, who was asleep when I came to bed, eventually was annoyed enough by the whine to wake up, just as I gave up on the bloody thing and reached to pull the hose and reattach it to my PRS, which was nearly silent in comparison.
Since I don't have the muffler, I can't say if that it a major improvement, but I took a decibel metre and sound pressure meter to it today, recorded a whopping 39 dB at 30 cm, which is how far away you are from your hose at maximum, and 37 dB at 100 cm, which is how far away your bed partner is, maximum. In comparison, the PRS output was 27dB at 30 cm and 22 dB 100 cm. The difference is remarkable. Moreover the sound pressure measurements were equally disturbing (.01Pa for the Z1 compared to .002Pa for the PRS at 100 cm). So I certainly hope a muffler make the difference, because as far as I can determine this all sound transmitted along the hose, and very little of it is coming up directly from the device into the air alone. Part of the fault is the far smaller air intake into the compressor (why? I can see a dozen easy ways to make that problem go away in the base design with a weight gain of at most a few dozen grammes), part of it is the fault of how the air outlet is done.
Another problem is the humidification capsule (again, I did not have a Z1 native capsule, but the GE standard disposable capsules, the same we use in the hospital) and here the problem is that it doesn't work on a P10 mask - this is designed to be close to the nose piece, not down at the far end of the mask's hose, so with the peculiarities of the P10 mask design, your moistened exhaled air doesn't reach the capsule to soak the sponge and make that moisture reusable on the next breath, or at least not significantly to be of real use in this situation.
Anyway, I am relying of the Z1 users here to tell me if there is a significant difference to the sound quality with the muffler before I submit my recommendation, which so far is pretty negative or a lot of reasons. I badly want this device to be good, I am rooting for it, but right now i have too many black marks against it and need some good reports.
Ok I have tested the Q-Tube with the Z-1 Auto and it does reduce the noise of the unit.
I have tested it with the stock 4ft 15mm hose., 6ft 15mm hose and a 6ft 22mm hose and at a fixed pressure of 13.
The only thing I could find is that different masks make more noise then others with it. I found that the higher the vent rate on the mask the less noise it will make with the Z-1
Full Face Masks tested with it are (Resmed Airfit F10, Resmed Quattro and the F&P Simplus) They did not make much noise even without the Q-Tube
The F&P Eson, Nuance Pro and Swift FX made the most noise without the Q-Tube (The Dentist's Drill Sound) They were almost silent with the muffler.
Okay, thanks, Crappy, it does help a lot. Was there much machine noise noticeable once the muffler was in place, with the various masks, or was that too reduced to near silence?
09-13-2015, 12:05 PM
(This post was last modified: 09-13-2015, 12:07 PM by Crappy.)
(09-13-2015, 11:29 AM)DocWils Wrote: Okay, thanks, Crappy, it does help a lot. Was there much machine noise noticeable once the muffler was in place, with the various masks, or was that too reduced to near silence?
It's hard to say, the sound level at the machine didn't change that I could tell. My Z1 doesn't make much noise. I think I got lucky and got a good one. All the noise was coming from the mask. I will have to bring my db meter home from work to see.
I also found that if you set EPR from APAP-3 to APAP-1 there is less noise.
You have to remember that little fan is spinning at 2 to 3 times the RPMS more then a full size unit and has no sound insulation.
It's a great little travel CPAP but not something I would use full time.
I have extensive use of Z1 and Z1 Auto, I use a Simplus full face mask, the Z1 is loud as $&:; !
The only way I can effectively sleep with the device is to use it with an F&P HC-150 attached.
I purchased and tried the new Q-Tube muffler, I could not notice any appreciable difference in perceived noise level. I tried it with slimline hose and standard hose, it made no difference. For me the Q-Tube was totally worthless, not to mention the requirement of changing foam core every 14 days. It's a total bust as far as I am concerned, not worth the effort.
Okay, conflicting responses to the Q-Tube. I get it about using a third party humidifier though, that would kill a lot of any vibration passed up the tube.
So, I have to have the report in on Tuesday (tomorrow everything is closed - Knabenschiessen, or shooting kids - a favourite sport around these parts, and the only day it is in season) and will be drafting it tomorrow, so any last thoughts and recommendations from users will be appreciated - methods of damping the noise, usability at home/for travel, advisability of use for home, tips and tricks, and general impressions what works, what needs improvement (besides forcing you to buy an iPhone to find anything out about your treatment with the machine - that is a big mark against it).
Any and all help will be appreciated.