I don't think the TE Connectivity (formerly known as Tyco) RQ73 series, thin film, 1206, 0.05%, 10ppm would be worse for the average audio enthusiast, that does not have to design for an industrial grade temperature range like 0-70 degrees. They are readily available and x2.5 times cheaper compared to the Susumu 5ppm. At the prices of the AP gear, those Susumu resistor are obviously fitting in. FWIW, the AP x555 performances are guaranteed over 0-45 degrees, that's still a wide range.
Last edited:
Looks like these are all non-stock items from Digikey and Mouser
He also said 'if you can get them' ;-)
Jan
You mean, 0.05% . A precision attenuator, precision CMRR for a differential gain stage, would be examples of applications worth of using these resistors. For example, a differential gain stage CMRR is given by CMMR=(Ad+1)/(4*t) where Ad is the differential gain and t is the resistors tolerance. For Ad=1 and t=0.05%, the CMRR is 60dB, which is good, but much worse than a precision op amp performance (anywhere between 80dB and 130dB).
. A precision attenuator, precision CMRR for a differential gain stage, would be examples of applications worth of using these resistors. For example, a differential gain stage CMRR is given by CMMR=(Ad+1)/(4*t) where Ad is the differential gain and t is the resistors tolerance. For Ad=1 and t=0.05%, the CMRR is 60dB, which is good, but much worse than a precision op amp performance (anywhere between 80dB and 130dB).
Hi all thought I'd share a video of a gentleman I know on YouTube doing a video build of the Jan Didden Auto Ranger. He's doing a great Job so far, and its nice to see this being built.
Autoranging Attenuator part 1 - YouTube
Autoranging Attenuator part 1 - YouTube
Last edited:
I have no doubt that given the engineering budget and time to do so, you would...especially if it was your only job...and if you are married, well there's at least half your time gone to start with! (apologies to Mrs. Didden...)
Thanks again Jan, I am looking forward to transitioning from AP to this platform after many years, now that I do not have access to the AP.
I have been trying the Virtins VI software, it seems extremely capable, but I am having trouble with it on my bench PC running Win7...although all driver setups completed without error, all outputs to the RMA look rapidly gated which of course ruins any test....it is always something, I wish Sy was still around to help with the Virtins software, he is a big fan of it. I cannot find any reference to this issue on the internet and will likely email Virtins.
There is something to be said about dedicated hardware with physical buttons to run tests (thank you Sound Technology!).
Cheers,
Howie
After using the RME ADI-2 Pro FS for a while, I would rather it had been larger with more buttons and controls and fewer menu levels. As it is RME had to condense the large menu structure into an obscure series of button presses and knob turns which I find difficult to memorize.
Such is the allure of software over hardware...even with just one knob and one pushbutton there is potentially an unlimited number of menu levels and items which can be selected. The ADI-2 has 6 pushbuttons and two rotary controls, and although I can tell an attempt was made to give a logical structure, it is daunting without the manual.
In addition the condensing of so much functionality into one small chassis makes it run hot as fire!
Cheers!
Howie
Last edited:
I have only limited experience with the ADI-2 Pro, but hope to acquire one next year. But I would think that using it as a sound card for measurements doesn't require the use of all the myriad options and settings. Like set once and that's it, in a way.
I do know that ADI's chief designer takes an autoranger with him, plus his personal ADI-2 Pro, when travelling and needing a high-resolution kit.
In fact, many of the improvement ideas from the first generation autoranger came from him, and there's more to come!
Jan
Best Autoranger ever ;-)
The ARII V3.19 is the latest version, which I have tuned with lots of suggestions and comments by Matthias Carstens*.
I am preparing a new set of data files for this version to put online. To wet your appetite, here is a write-up from Matthias based on his use and measurements of the unit.
Watch this space!
Jan
*I am highly indebted to Matthias for his engagement with this project. Every designer needs someone who kicks him once in a while and calls out his often questionable views. Without his inputs it wouldn't have gotten to where it is now. And, should you need a soundcard, RME has you covered!
The ARII V3.19 is the latest version, which I have tuned with lots of suggestions and comments by Matthias Carstens*.
I am preparing a new set of data files for this version to put online. To wet your appetite, here is a write-up from Matthias based on his use and measurements of the unit.
Watch this space!
Jan
*I am highly indebted to Matthias for his engagement with this project. Every designer needs someone who kicks him once in a while and calls out his often questionable views. Without his inputs it wouldn't have gotten to where it is now. And, should you need a soundcard, RME has you covered!
Amazing performance, Jan!
I have not put my AR through the close analysis Matthias has, but with the ADI-2 Pro FS I can easily test down to the noise floor of anything i connect to it.
I have been using REW, but plan on looking into Virtins when I have more than a minute in the lab...which is undergoing renovation as I type. To free up space I am disposing of test equipment more than 2 generations old with few exceptions...I have already donated an HP DVM and Frequency Counter to a local ham radio operator.
Anyone interested in a Tektronix TM6000 frame with an AA5001 Audio Analyzer, DM5010 DVM and SG5010 Signal Generator? How about a ST1500A or 1510A? Since building the ARII I seldom turn any of them on any more. The only thing I miss so far is the ability to see the residual signal (THD/IMD/Noise/Wow/Flutter) available on a BNC output to scope as both the ST1510A and the AA5001 allow. It is possible some of the analysis software will output this during analysis, I had not checked into that function yet.
Cheers and best wishes for a better 2021 for you all!
Howie
I have not put my AR through the close analysis Matthias has, but with the ADI-2 Pro FS I can easily test down to the noise floor of anything i connect to it.
I have been using REW, but plan on looking into Virtins when I have more than a minute in the lab...which is undergoing renovation as I type. To free up space I am disposing of test equipment more than 2 generations old with few exceptions...I have already donated an HP DVM and Frequency Counter to a local ham radio operator.
Anyone interested in a Tektronix TM6000 frame with an AA5001 Audio Analyzer, DM5010 DVM and SG5010 Signal Generator? How about a ST1500A or 1510A? Since building the ARII I seldom turn any of them on any more. The only thing I miss so far is the ability to see the residual signal (THD/IMD/Noise/Wow/Flutter) available on a BNC output to scope as both the ST1510A and the AA5001 allow. It is possible some of the analysis software will output this during analysis, I had not checked into that function yet.
Cheers and best wishes for a better 2021 for you all!
Howie