Having had the QuantAsylum logo in the upper right-hand corner covering up important data, would it be possible to have a setting where this logo is able to be turned off globally and in the automated tests?
I would also like to remove the Logo from the corner, or be able to put it somewhere else. It often gets in front of important data.
There is an option to do that under edit>settings>suppress logo. You’ll have to restart the application for this to take effect.
Personally, I wish there existed a way to turn off the information in the upper left hand corner of the graph screen - in my usage, this information almost always covers up the lower frequency portions of my readings. This information display is mostly redundant to me anyway, and I never read it, but it seems to have a way of covering up my graphs.
Hi @tspacker, @Rammis is correct. But it just needs an acq cycle to honor your wishes, not a full re-start.
An upcoming change in 2.0 will have a lot more on-screen elements, but you’ll be able to collapse them and drag them around. It should help a lot with the scenario you mention Rammis! I feel that pain too.
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Hi Matt,
A couple other things would be great on the next version…
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In the THD graph, when we enable the right channel, the numbers at the top of each bar disappear. I find that information very handy but I need also both channels in the graph. Would it be possible to show both values side by side at the top of these bars? And an option to show them in % would be great two as it’s the way we usually read them in manufacturers specifications.
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When I calibrate my R2R (read Reel-to-reel), there are strategics frequencies that are important to see on the FR function. So I first use the GEN1 button to generate a 1 kHz tone and click on it’s top to record the peak of this frequency. Then I repeat this step for each strategic frequency; 30, 60, 125, 250, 400, 1k, 4k, 8k, 10k, 16k, and 20 kHz. Then I go back to the FR domain to plot the frequency response of the deck. The great idea of it is that the maximum peak is always show at the top and all the other frequencies show their relative value in reference to the maximum. That way I can calibrate the deck while trying to achieve the lowest difference in dB between the maximum one and all the others. Here is a capture of an example:
Now those frequencies stay visible in most of other functions until I close the QA40x software. Even if I save my settings, the peaks frequencies aren’t saved and I must redo the GEN1 steps every time I start the software. Would it be possible to save these peaks frequency settings in the save settings function?
- When we right-click in the THD to copy the graph, the image doesn’t include the tiles at the top of the graph. An option to also capture the tiles would be great seeing that we also want to know their %. For now I use to do screen captures instead of using the copy image function.
That’s it for now. I only have the QA40x for less than a week so far but I am very happy to have it and I am impress by it’s very good quality. In the past, in order to calibrate my R2R, I tried a DM-RTA without any good result, I also tried REW but I do prefer by far the QA40x hardware box for it’s quality and simplicity!
Keep the good job! 
Kind regards,
Yves
Hi @Tube709, thanks for the valuable feedback. While you are “repeating the step for each strategic frequency” are you making adjustments between each step? Where are you getting the test tones on the tape? Are they from a reference tape? Or can you record a signal and use that as the stimulus? If so, maybe you can record a chirp and then use a triggered acquisition. You should then able to normalize that. But it depends on whether you are able to use a self-generated source tone/chirp or if you have to rely on pre-recorded tapes for your tones. Based on your answer, I’ll see if there’s a way to speed this up.
If you want to capture the measurement tiles along with the graph, use the Edit->Copy Bitmap to Clipboard.
Only changing the frequency on the GEN1, then I click the peak of the new frequency. It is just to have the list of frequencies and their respective dB value in the table, like with the THD. But the goal is to still have the table while I am doing the Frequency Response of the R2R in Record mode.
I record a signal and use that as the stimulus.
The tones come from the QA403 itself when I do the “FREQ RESPONSE” function. I inject the QA403 OUTPUT into the Input of the R2R. I activate the record on the R2R and I monitor the recorded signal at the Output of the R2R ( the one from the Playback head), back into the QA403 INPUT while I am doing a Frequency Response plot.
Because I did create the frequency peak table with the GEN1 generator, the table is still available into the “FREQ RESPONSE” function.
It is then very easy to calibrate the BIAS of the R2R while observing all the dB values of each frequency. You want to stay in the manufacturer specifications, like:
*30 Hz to 20 kHz +/- 3 dB*
Great! That exactly what I was looking for
Hi @Tube709, thanks for the additional detail. So, you are recording a signal using the record head, and then that gets played back a short time later with the playback head is that right? And the time consuming task here is just loading up the frequencies you want so that they display in the table format?
I think that type of formatting might be best done in Excel. You could export the sweep, and then tell Excel the freqs you are interested in and have it interpolate a table for you. That way, you spend some time getting it just right in Excel, and from then on you can pull in any spectrum data and get the callouts you need. Is that an option?
Yes
Except that it is played right on, live…
No !
I was using Excel already and it is time consuming.
While with the QA403 it is done live while I am doing the calibration !
Think of a FR where you are adjusting trim-pots live while you are watching the results live.
You have 2 trim-pots to play with , the BIAS one and the EQ one.
The BIAS give energy while the EQ set the high frequency equalisation.
I dont mind to use the GEN1 to create my table myself. What I would apreciate is if the “save settings” could also save those frequencies peak created in the THD view…
Pictures are better to understand the goal 
On one of my R2R, a Technics RS-1500, there are two switches; BIAS and EQ. Each switch have three positions; 1-2-3.
When you calibrate the Record Amplifier of a deck, you should calibrate it for the specific tape formula you will use. In my case I buy only LPR90 tape type formula. Originally in the 80th, the tapes formula weren’t as good as today tapes and a lot of company fabricated them. The manufacturer was calibrating the machine for a reference tape formula and they were giving you a reference table to set the BIAS and EQ switches for the tape you would use, like this one below:
Note that originally the manufacturer has calibrated the deck with a RT-10B218 tape formula, that is similar to the Scotch #207 as mentioned at the bottom of the table.
Me I calibrated for my LPR90. Once the deck is calibrated following the maintenance manual procedure, I still have the possibility to look in the FR plot of the QA403 to see what is the result when I play with the BIAS and EQ switches. Two switches with each 3 positions give 9 different possibilities of the BIAS/EQ settings:
BIAS=1 EQ=1
BIAS=1 EQ=2
BIAS=1 EQ=3
BIAS=2 EQ=1
BIAS=2 EQ=2
BIAS=2 EQ=3
BIAS=3 EQ=1
BIAS=3 EQ=2
BIAS=3 EQ=3
Now, first I use the QA403 to show the THD. Then I have the liberty to click on any peak to have it’s dB values in a table. My goal here is to click on specific frequencies, like those in the previous post above.
Once that is done, I switch the QA403 in the FR view. The table stay on the screen!
That’s the tool!
While I am looking at the FR screen, I play with the two switches and compare the result trying to get the least difference in dB of all my strategic frequencies. That would result in the most linear FR!
Here are three captures showing the result of BIAS=1 EQ=1, BIAS=1 EQ=2 and BIAS =1 EQ=3 respectively…
“TAPE” 19 cm/s BIAS 1 EQ 1 gauche et droit -44 dB
“TAPE” 19 cm/s BIAS 1 EQ 2 gauche et droit -44 dB
“TAPE” 19 cm/s BIAS 1 EQ 3 gauche et droit -44 dB
The table show the relative dB value referred to the highest frequency and I can visually read the worst frequency in my table. In the case where it PASS the PASS/FAIL settings, I see that my worse frequency is 16 kHz (15,99 kHz) at -3.16 dB while the 14 kHz (13.98 kHz) is at -2.12 dB in reference to the highest frequency 4 kHz (4.009 kHz) at +1.39 dB.
As mentioned previously, I don’t mind to create the peak table in the THD function with GEN1. What I look for is if the “save settings” could also save the peak frequencies values chooses.
This is one example of the use of the FR table. But it would be a strong tool also when you calibrate the deck playing with the BIAS and the EQ trim-pots inside the deck… You would see the curve live while you trim the pot as well as seeing the frequencies affected and their dB value!
I am curious if @Tube709 has checked out the inexpensive NAK T-100 software for tapedecks. All that is needed is an ADC like the Behringer UCA202…?
No I didn’t, but on your suggestion I just did…
Even if it looks very cool, I don’t like the fact that it is based on an internal or external audio card. I was already using REW software with a Focusrite Scarlett 2i2. Plus when I compare the specifications, it seem a bit limited with a 20-20 kHz frequency response, a 0.01 % lower limited THD and below that table capture below, some notes that I cut/pasted refering to the topics I don’t want to depend on…
- The specifications may vary depending on actual sound card used.
- Calibration will be needed prior to working with a specific audio device on a specific computer.
- The computer must have standard stereo audio input (line-in) and standard stereo audio output (regardless of built-in or external) in order to allow the app functioning properly.
- The app does not have hardware-level control on sound device. All sound configurations (such as sample rate, bitdepth, channel map and I/O gain) must be done with the standard tools provided by the Operating System.
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Am glad at least you checked it out. The calibration procedure is pretty easy. I have only used it with a few cassette decks, and just 3 head ones. Actually, the Behringer has line level in/out RCA jacks and a usb cable that plugs into your PC, and the NAKT software can then see it. The specs on the Behringer ADC are pretty decent compared to those of a cassette deck- have not had any R-R decks on my bench so not sure how much better they would be. The more things you can do with a QA40x, the merrier…