Got your VM -- was entertaining grandkids at the time! (They ate, between themselves, a pound of shrimp and a pound of linguini.)
I have a modified macro of "FFT-Scaling for Noise" which simply converts the y-Axis to V/Rt Hz, and the x-axis to log, and an opportunity to adjust for the gain of the LNA.
The “Audio Precision” Box is a tool to help an ANALOG/DIGITAL ELECTRONIC ENGINEER to understand or verify that the electronic product is correctly working. It also used with a DVM, OSCILLSCOPE and other tools to in production testing.
If you are not skilled in a form of science, how can you say it cost to much.
If you are not skilled in a form of science, how can you say it cost to much.
Strange statement...
Any EE "engineer" doesn't need a "“Audio Precision” Box" to get feedback vs their design, unless they need to be "high" in the ranking of ASR.
Any EE "engineer" goes "deeper" by default, using smarter measurement devices ...
Any EE eng, use : DSO / sampling scope / VNA / SA
No EE eng, use a "AP" device to draw conclusions,
phile1,Hi,
rough reply vs the many threads related to the thsi subject :
AudioPrecision devices are for the guys like Amir from ASR that are lazy and want "result", without thinking about "what's below?"
The kind of of guy that does't want to have his brain "pushed too far", or even nicer pushed to "non-sense" vs physics... blabla bla...
The best answer to this kind of threads => go deeper !
buy the awesome LiteVNA and TinySA for 1/100 price of any AudioPrecision stuff
then, thru measurements using LiteVNA & TinySA => you end to some info & conclusions.
If this infos from TinySA & LiteVNA don't rig a bell to you =>
1. you realize this game is to big for you, no brainer => you'll learn very nice stuff ahaed, and gonna be ccol
2. you're stuck to AudioP devices => you're ****** / fooled
why this ? => AudioP devices/ measurements, are like sniffing the exhauts pipe of a jet or piston engine and "guess" what right/wrong INSIDE the engine without knowing anything about this inside of the engine. Weird isn't it ?
all the best for the ones that looks deeper
and good luck for the another ones
You had a previous post with similar content already.
If you want to feel good and look down on others by claiming you don't need an AP to do your job then suit yourself. But you don't have to bring it up and brag every now and then.
What do you propose to measure linearity? And SINAD or SNR to the accepted standards?
oups...
I'm not trolling
I just like to understand things, so I use basic measurement devices like
1. "time-domain" analyzers
2. "frequency-domain" analyzers
both above are "basic" analyzers...
"basic" in the sense : "raw"
Audio Precesion is not "raw"...
To be clear : how many companies compete with AudioPresision ? none
Why ?
because it is a doggy market, so all Keysight / R&S & co : they go away vs this market.
Only AP remains...
oups...
I'm not saying AP is total crap
I'm just pointing that AP are "black box" that give "results"
So, as a "I don't know anything but I can learn" guy, feel free to
1. explain a AP measurement is relevant
2. vs a combo time/freq-domain analysis using common measurement devices
oups ! I've forgotten a key point about AP stuf : they are plug&play or plug&measure (depends how you want to call it)
but "fair" measurements are not plug&play.... I admit that's a PITA but we have to cope it
@phile1: I am not sure what you mean, but IIUC AP is a standard ADC sampling to PCM and a software doing standard time -> frequency math. The hw does some signal conditioning (like merging the stream from two digitally filtered ADC channels, one direct (bandpass filtered) and second via notch (bandstop filtered) - but it's just to gain resolution, the result is again PCM. The final numbers (like THD, IMD, etc.) are always a result of some parameters (bandwidth, etc.) so we can see discussions why e.g. REW yields slightly different numbers than the AP software. But those are minor differences due to slightly different input parameters to the calculation.
You are not trying to understand things. You give nonsense opinions and insults based on ignorance. You are a troll.
Jan
be cool !
"troll" stuff : it's the very common garbage you can see all around this days. Not my cup of tea.
If you find smth wrong in my tests/ results => do your own to compare.
Then, no brainer, we share results etc...
I'm just trying to understand things...
You say "troll" vs me =>
1. why not
2. what kind of measurement ever you perform of any "electro" device ?
3. just share you experience instead of "woo vs that" !
Again, What do you propose to measure linearity? And SINAD or SNR to the accepted standards? those are accepted standards that generally need specialized instruments to evaluate. Same for eye-patter or return loss/crosstalk on CAT cables etc. etc. You may be able to measure frequency response with an oscillator and a meter (really tedious) however distortion requires some method to remove the source and evaluate the residual. Spectrum analyzers today are not good enough to measure the distortion residuals of current audio products.
AP analyzers are expensive but they have well understood performance that can be verified with a few other simiar devices (Shibasoku?)
AP analyzers are expensive but they have well understood performance that can be verified with a few other simiar devices (Shibasoku?)
Good afternoon. I am wondering if anyone has a System One USB Interface they would like to part with. I've had a One for years but don't have the ISA card that came with it (or a computer that has an ISA interface!). I would like to get it working to do audio analysis with my repair business. Please let me know if you would part with one. Thanks.
Good afternoon,
Could you please help me at the conversion of my System One Tests in APWIN like in the ap manual:
https://www.ap.com/category/news/translating-system-one-dos-files-to-apwin-ap2700-or-ats ?
According to the notes it will be necessary to have APWIN 2.14 and 2.24 installed, but at RELATED DOWNLOADS (bottom at the end of the conversion-manual) only exist a download link to APWIN Control Software v2.24 without link to the v2.14.
Could somebody please send me the download link or the installation package for the APWIN Control Software v2.14?
It would be great and very helpfull for me!
Thanks in advance.
Could you please help me at the conversion of my System One Tests in APWIN like in the ap manual:
https://www.ap.com/category/news/translating-system-one-dos-files-to-apwin-ap2700-or-ats ?
According to the notes it will be necessary to have APWIN 2.14 and 2.24 installed, but at RELATED DOWNLOADS (bottom at the end of the conversion-manual) only exist a download link to APWIN Control Software v2.24 without link to the v2.14.
Could somebody please send me the download link or the installation package for the APWIN Control Software v2.14?
It would be great and very helpfull for me!
Thanks in advance.
There's some element of that. The AP gear just works. I plug stuff in, easily configure the software, and it spits out a pretty plot without much fighting over it. With an external sound card I have to fight software that wasn't made for the purpose, weird cable issues and/or USB ground loops. That takes time, increases my frustration level, and reduces my confidence in the results.
Such people would probably not be able to justify the cost of the AP gear. They'd buy a sound card.
That's not exactly true. The AP can measure just about any audio parameter under the sun. But it won't tell you that the equipment under test will sound SuperDuper FlappyDappy, have more PRaT, or KaPLuNk (or whatever other meaningless audiophile term). That's for you to figure out from the results. For someone skilled in the art, the AP can tell whether the equipment under test is sonically transparent or not; or whether it has the desired sonic signature or not.
I wouldn't be able to design or verify the circuits that I offer without the APx555. So to me it's pretty bloody useful. The fact that it works well across a wide range of frequencies and voltages is a must-have for me. A sound card tends to work well at one frequency, voltage combination.I even more do not understand how someone can use a AP gear, given that :
so... why using a 10kEur device...
- it's very very pricey (>10kEur), although it can give poor/few results
- in the market we have many very cheap devices (@ 100Eur) that able anyone to investigate at PCB level "what's going on ?"
please help me to understand how bloody useful an AP gear is !
Now, don't get me wrong. When I mailed off the cheque for the APx555 it was not lost on me that I just spent about 2/3 of the average annual pre-tax income for a single Canadian on one instrument. I could have bought a very nice used car for that ... or a decent new one. But I had been trying to squeeze out more performance from the APx525 for years and couldn't get the performance enhancements to work reliably, so I decided to punt and get the 555. I have never regretted that. I love that I can measure THD well below -140 dBc without even trying. To me that's useful and to me that makes the 555 worth the high price tag.
But hey... We don't all have to like the same stuff. If you'd rather have a $150 external sound card (I recommend those by Focusrite) have at it.
I commend OP's efforts into keeping the older instruments going. They're every bit as good now as they were the day they were launched. The SYS-2700 is a smidge better than the APx525, which offers plenty of performance for most people. And I suspect a nice feature of the even older systems is that it's vastly more plug-n-play than an external sound card - and it works well across a range of voltages, frequencies. A System One is not that much more expensive than an external sound card but offers more flexibility, so I can certainly see the attraction there too.
Tom
Hi tomchr,
I understand your point about the APs !
But honestly, I can't understand why people use them...
simply because they give no info about : "how does the audio chain work ?"
I mean :
Honestly, it's far more fun to do basic electronic DIY experiments to look at basic/tiny parts of a PCB and improve them rather than doing any overall checkup with a AP
I understand your point about the APs !
But honestly, I can't understand why people use them...
simply because they give no info about : "how does the audio chain work ?"
I mean :
- just looking at a USB-to-spdif interface, there are many stuff within this interface that affects the sound.
- but using an AP, you can't know where the bottleneck is ! Simply because any AP does an overall check...
Honestly, it's far more fun to do basic electronic DIY experiments to look at basic/tiny parts of a PCB and improve them rather than doing any overall checkup with a AP
Nothing prevents you from measuring each building block within a design independently. I do that on occasion during debugging to figure out where the bottleneck is.
Nothing prevents you from looking at a PCB, making changes, and measuring the changes with an AP either. I've spent the past two weeks doing that.
I certainly find the AP useful for determining the impact of a change, for example the impact of changing a resistor as I did here: https://www.diyaudio.com/community/threads/modulus-86-build-thread.267802/post-7709863. Read about a page of that thread starting with that post.
If you can't measure an improvement how do you really know that you've improved anything?
Tom
Nothing prevents you from looking at a PCB, making changes, and measuring the changes with an AP either. I've spent the past two weeks doing that.
I certainly find the AP useful for determining the impact of a change, for example the impact of changing a resistor as I did here: https://www.diyaudio.com/community/threads/modulus-86-build-thread.267802/post-7709863. Read about a page of that thread starting with that post.
If you can't measure an improvement how do you really know that you've improved anything?
Tom