GSI Quality Handheld Digital Frequencies
I purchased a SanDisk 32 GB microSDHC Flash Memory Card SDSDQM-032G nearly two months ago, for use in my VIZIO 8-Inch Tablet VTAB1008. At the same time, I also purchased a higher-priced PNY 32 GB microSDHC Card (P-SDU32G10-EFS2) which is supposed to be a 'class-10'. My benchmark results, however, show that the Sandisk class-4 card is actually faster - most of the time.
I used two sets of benchmark programs. One is called 'Flash Memory Toolkit v2.0', which measures the random read/write speed of files between 1MB and 15MB. The other one is called 'H2testw v1.4', which measures the sequential read/write speed using 1GB files. Here are my results: (see my uploaded charts in 'Customer Images' section for details)
- For smaller files (1-5MB), the Sandisk class-4 card gives an amazing write speed of 15-17MB/s, while the PNY 'class-10' card can only get 1-6MB/s
- For larger files (10-15MB), the Sandisk and PNY cards are about equal at around 8MB/s for write
- For huge files (1GB), the PNY did better at 9.5MB/S, while the Sandisk dropped to 5.5MB/s
- The read speeds of both cards are equally high at around 18MB/S (this number may be limited by the maximum speed of my card reader used)
What the above shows is that: When used in a typical digital camera (with file size 3-5MB), this Sandisk 'class-4' card is at least twice as fast as the PNY so-called 'class-10' card. But when used in a HD video camera (sequential writing of huge file), then the PNY card should perform better.
For a card to be marketed as a 'class-10', it must maintain a MINIMUM write speed of 10MB/s. So by this definition, the PNY card does not qualify since it cannot even achieve a MAXIMUM write speed of 10MB/s. This Sandisk card, on the other hand, exceeds the requirement of 'class-4' by a huge margin.
Sandisk seems to be the only flash memeory manufacturer that still gives honest, conservative speed class ratings. Any other manufacturers would have labeled this card a 'class-6' or even higher. As a matter of principle, I rather give my money to a company that promises less but delivers more, instead of to others that do the opposite. At the present cost of about 1 buck per GB, this is an unbeatable deal!
[Aside]
The capacity of this card, as reported by my computer, is only 29.7GB. Note that this is actually normal, because compter people define one 'Giga' as '2 to the power 30', which is 7.4% greater than 1 billion. So 29.7GB comes to just about 32 billion bytes, which is '32GB' according to marketing people.
[Update Dec 3, 2011]
I re-tested the two cards above, using the CrystalDiskMark v3.01. The results are consistent with my previous finding. See my newly uploaded charts in 'Customer Images' for details.
I am sensitive to noise and found myself wondering about the DB noise from a variety of sources, ranging from nearby traffic to the fans in my office.
BalasHapusI got this sound meter because it was inexpensive, and because it looked like it had the main feature I wanted: the ability to capture sound and show DB in a variety of environments.
I found the measurements fairly consistent, give or take a few DB. It was easy to use, and easy to understand. I think it's good value for money.
I bought this to see how loud i was listening to music in my car. It does have an A and C rating to measure different frequencies (C are the lower frequencies). It seems to work well. However i don't know how accurate it is, as i have no way to compare it to an actual standard.
BalasHapusit can test in a good DB range. I use for small indoor shows that usually have bad lay out- concrete walls. This helps me get a good idea of how much sound we can pump into the room without making everyone permanently deaf. It works good for the price.
BalasHapus
BalasHapusI bought this to calibrate my home theater systems and it gets the job done. Very solid piece and easy to use. Has many setting such as: fast/slow and a/c. Price is reasonable for the quality received.
BalasHapusI am a Motorcycle rider in the state of New Hampshire , NH just passed a law on Loud pipes the law has grey areas, the inspection of bikes has grey areas , so i purchased my own meter to see where i stood . it is very accurate considering the cost , and yes my bike did pass the test just coming in at 91db at idol. Good to have if you get pulled over and he police try to do a field test you do your own and record it with your cell phone.
BalasHapusLoud Pipes Do Save Lives, the saved my Life once.
I do music recordings in a make-shift studio that I have set up at my house. I have started using this to get a better balance of sound out of everyone without the pain of trying to do it all with the mixing board. So far so good, I read the instructions (never had one before) it was understandable and explained not only how to use it clearly. It's kinda light but, that's good for my gig bag when I'm playin' out. 5 STARS.
BalasHapusWorks as described. Used it to refine system of 137 speakers and they all are balanced as well ass can be expected. Even in noisy areas, it worked well.
BalasHapus