That's typical of an old very public e-mail address. Gmail does a very good job with those. I forward the attglobal.net address of mine to gmail. Filtered at least 100 spams today so far. And really smart filtering. I have not been hit up for millions from Nigeria for months. Gmail has a much better interface than the older systems.
Finally making some progress with the AP2722....got instructions on how to remove the Dolby pcb/wires to disable it. Done. FFT seems to work but only to 4096 setting. Now what? And, the internal generator shows 2H and 3H at 110-120 levels. Have to look it that, too. Another call to A_P about these two matters.
Still have to install the optional IM pcb . Cant find the instructions - around here somewhere... but under which pile?
Good news? The new i7 is fantastic..... The SSD is amazingly fast. So, I took my 5 year old All-in-One desk top and had the HDD replaced with SSD. This is really a good thing to do to your computer. Prices have come down to $1/GB now. Maybe less somewhere else.
PS- Judging by the looks inside the analyzer -- I have to admit it IS, unfortunately, worth the asking price.
THX-RNMarsh
Still have to install the optional IM pcb . Cant find the instructions - around here somewhere... but under which pile?
Good news? The new i7 is fantastic..... The SSD is amazingly fast. So, I took my 5 year old All-in-One desk top and had the HDD replaced with SSD. This is really a good thing to do to your computer. Prices have come down to $1/GB now. Maybe less somewhere else.
PS- Judging by the looks inside the analyzer -- I have to admit it IS, unfortunately, worth the asking price.
THX-RNMarsh
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Dick -- i will be interested in your comparison of the "software-in-solder" version of the IMD card-analyser and the software-only option which is standard on the 2722.
My new Samsung laptop came with a 125g SSD, and it is amazingly fast. It's also amazing, however, how much of that memory is consumed by the new Windows and MSOffice Pro.
My new Samsung laptop came with a 125g SSD, and it is amazingly fast. It's also amazing, however, how much of that memory is consumed by the new Windows and MSOffice Pro.
I might have to do that software IM before installing the hardware IM pcb version.... otherwise, maybe, both wont be available (?).
I saw the power of the SSD at CES a couple years ago but price was too high at that time. Now it is much better --- the floods in Thailand - where HDD are made - caused a shortage and lose of sale which the industry never forgot.... and boosted production of SSD to cover PC production etc. I was in Thailand at that time and got out by the skin on my teeth... as the last airport available which had not been flooded (yet) and an empty seat was found. Otherwise, we would still be at the price of a few years ago. There is no need for HDD any more -- and the SSD consume less battery power for portables. My upgraded HDD to SSD yesterday on a 5 yr old desk top... is wonderful. Especially, the WIN boot-up time is like in a few seconds.... a beautiful thing to behold! Turn on the PC and Pow! - its ready to use (its a Samsung SSD, of course)
-RM
I think SSD will replace HD completely if the size becomes compatible. Then we will see the price drop. I always wondered why manufacture didn't just go this way years ago. Still money to be made on the old tech I guess. Why "Samsung of course"? is this a better product or just because they are taking the market?
The storage density per $$ is still much better on spinning disks. Also the service life. Some applications will reduce an MLC SSD to trash in a few hours. Its all tradeoffs. I have a 250G Samsung 840 pro SSD in my main system but the data (800 GB of it) lives on spinning media. Its probably the best mix today. I'll move the data to a NAS soon to further clean up the setup.
I see so one doesn't want to use them for FFT processing or other data intense use.
I have system on SSD and a combo drive as my second and with most all files are on combo HDD. But I have to see how long SSD lasts. However, it is sooo fast I would not mind replacing it More often than a HDD.
HDD are getting cheap but they still are not fast enough for me. I don't think I'll ever go back to HDD except as backup or file storage. And, SSD can only get better... HDD is pretty mature now.
-RM
HDD are getting cheap but they still are not fast enough for me. I don't think I'll ever go back to HDD except as backup or file storage. And, SSD can only get better... HDD is pretty mature now.
-RM
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The killer is intense database use. Even SLC's are stressed for that. Google will be on spinning media for a while, with servers with lots of ram for disk cache.
FFT's really need RAM, not swap space. And nothing short of the really large ones will stress a modern system.
I'm surprised that the AP doesn't have really large (1M+ point) FFT in the software.
Comparing FFT data results -
I looked at the FFT data of three tests -- from 3 sources and 2 FFT's (1v/1KHz):
Using the AP2722 - the 2H levels differed the most over time - about +/- 2dB (4dB total). More variation if the instrument isn't warmed up for at least an hour. Seems to be all thermal related.
The K-Hite 4402B generator with simple opamp and trimmer upgrades, measures almost as well as the A-P -- 2H = -122-126dB and 3h= -114dB
The ShibaSoku AG16B measures -- 2H -124dB and 3H = - 118dB
The A-P 2722 internal generator measures -- 2H -130dB -126dB and 3H = -116-118dB.
But from a QA400 (using ShibaSoku AG16B generator): we get these levels: -->
THX-RNMarsh
I looked at the FFT data of three tests -- from 3 sources and 2 FFT's (1v/1KHz):
Using the AP2722 - the 2H levels differed the most over time - about +/- 2dB (4dB total). More variation if the instrument isn't warmed up for at least an hour. Seems to be all thermal related.
The K-Hite 4402B generator with simple opamp and trimmer upgrades, measures almost as well as the A-P -- 2H = -122-126dB and 3h= -114dB
The ShibaSoku AG16B measures -- 2H -124dB and 3H = - 118dB
The A-P 2722 internal generator measures -- 2H -130dB -126dB and 3H = -116-118dB.
But from a QA400 (using ShibaSoku AG16B generator): we get these levels: -->
THX-RNMarsh
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Its interesting that you are seeing more third harmonic than second. Here is what I get using the Shibasoku 590AR at approx 7V into the Shibasoku 725 on the monitor out. On the monitor out of this unit 1V = -90 dB. On the Wavetek display the top line is 1V= 0 dB. The fundamental is -126 dB (-136 diplayed) the second (always the highest in my measurements) is -124 dB and the third is - 132 dB. This is what I get with the Shibasoku generators.
The second picture is my modest KH4400 with the LME49990 mods and judicious tweaking of the distortion control. I know if I even wave the tweak tool at it it will never be this good again. As you can see the fundamental is the same and the second is lower than the 590AR at -132 dB (corrected). However the noise floor is not quite as low as the 590AR and it does not have the same drive as the KH4403, which can drive a 50 Ohm load.
I suspect the AP may need some "tuning" or your setup needs more optimization. It is supposed to be better than this.
The second picture is my modest KH4400 with the LME49990 mods and judicious tweaking of the distortion control. I know if I even wave the tweak tool at it it will never be this good again. As you can see the fundamental is the same and the second is lower than the 590AR at -132 dB (corrected). However the noise floor is not quite as low as the 590AR and it does not have the same drive as the KH4403, which can drive a 50 Ohm load.
I suspect the AP may need some "tuning" or your setup needs more optimization. It is supposed to be better than this.
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Davada -- No. about 1db below 1v. All are used as straight from the box.
Demian -- no attempt to tweak any of them. They can be tweaked for less 2H or less 3H. I am still fiddling with things to get better data --->
BUT - look at the QA400 and what it shows is very different than the others. Much higher. How good is it with a null on the fundamental? Something to check but it definitely can not be used without doing so if you want to have accurate data at the lower levels of distortion harmonics. Note too all the trash... the A-P doesn't have any trash/grass growing/extraneous freqs.
[incidently, the new i7 portable computer used here -- no difference with noise/grounding if on battery only or ac powered]
-RNM
Demian -- no attempt to tweak any of them. They can be tweaked for less 2H or less 3H. I am still fiddling with things to get better data --->
BUT - look at the QA400 and what it shows is very different than the others. Much higher. How good is it with a null on the fundamental? Something to check but it definitely can not be used without doing so if you want to have accurate data at the lower levels of distortion harmonics. Note too all the trash... the A-P doesn't have any trash/grass growing/extraneous freqs.
[incidently, the new i7 portable computer used here -- no difference with noise/grounding if on battery only or ac powered]
-RNM
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WIN8. I use two different computers.... In different rooms.... one for the tests (WIN8)and the other to send/read email and to read DIYAudio at a desk/office (WIN7 Pro). Its just fasterr this way for occasional use... I probably wont be keeping the data. Just quick points of note especially the numbers QA400 generate with same generator source.
[BTW - I do have a message into A-P tech about its performance... I have to do a self test and report the results to tem to analyze. But so far they say my numbers meet specs. I don't think something is quit right though. They do not recommend WIN8 though.. haven't found out why yet]
[BTW - I do have a message into A-P tech about its performance... I have to do a self test and report the results to tem to analyze. But so far they say my numbers meet specs. I don't think something is quit right though. They do not recommend WIN8 though.. haven't found out why yet]
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Another trick that makes my life easy- network them and use VNC (UltraVNC VNC Remote Support Software Desktop Control Free Opensource) to remote control the systems. That and shared directories allows lots of flexibility.
I often am using an XP system to make acoustic measurements running it from a Win 7 machine elsewhere in the house. Of course the Linux world is even better for this stuff.
I often am using an XP system to make acoustic measurements running it from a Win 7 machine elsewhere in the house. Of course the Linux world is even better for this stuff.
He's not using the analog notch filter, so he's actually testing the ADC, not the oscillators.
Samuel