Recent content by jesperlykke

So I did some measurements. I tried to create a calibrationfile for the IEC711 Clone, with an UMIK-1 as ref. Also I tried the calibrationfile provided by the seller. But I think the results are more accurate without any calibration at all. -Compared to FR on them Hifiman on different web...

Hey @sm52 I did not do any calibration of the mic. (not yet anyway) There is a calibration file in a .zip file I recieved from the seller, but I did not try this yet. I read over at ASR that those cal. files was nogo, but sure I will try it out anyway.

Hi all... I'm prototyping my diy artificial pinna headphone/IEM testrig. So far it's just a prototype, a rig with 2 silicone ears munted on rund plates as can be seen on pictures. The mic. is an IEC711 clone (Phantom powered) I'm waiting for some coupler attachment to glue into the measurement...

Hi here. SRY... guy's I overlooked the choice in the settings dialog, what to show... So it's solved... sry... :T I'm testing some headphone amplifiers, and I would like to show the e.g. THD or THD+N levels for 3 different stepped sine THD vs level sweeps (15ohm, 20ohm and 33ohm load) I cannot...

Thanks @phofman ... First I installed the 64bit version of Bookworm. Then the JDK17 from the Bookworm repo. I then installed the temurin-8-jdk. No change to java with update-alternatives or like. https://unix.stackexchange.com/questions/749903/how-can-i-install-java-8-on-debian-12-bookworm...

This is what happend when trying to execute REW: (Still on 32bit Bookworm)

Hi here... (I used to have REW running on the old Raspberry 32bit "Buster" version, but I need a newer version for other stuff on my RPI toolbox.)... Therefore :: I'm trying to install the java 8 package, but it's not "possible" on the Bookworm release (32bit). Is there another version that...

Nice you figured it out! But you should really create your'e own calibration file, to be sure that the notch is up to date allway's. I also create different compensation file's depending on the ADC's input level (could be 1.7V or 4.5V), also if the notch have some 0dB and +6dB setting, I have a...

Hi johny... Please read my other thread regarding the use of an compensation curve https://www.avnirvana.com/threads/measuring-freq-response-with-a-deep-notch-cannot-measure-the-correct-depth.11825/

Hi Johny... Yes you should use both external notchfilter + the AES17 notch. The AES17 is to take care of the sinewave's "skirt" Jesper.

I see... thanks... So A is just a calculation i see, makes good sense. Will dig some more into this next few days :) Jesper.

So after some time, I stumbled upon the (A)weighted measurement. I'm not aware of which kind of numbers I got using my calibration file as pr. instructed here in post #16 to #18. Or is it possible to change something and get (A) measurements or do I allready get that. I'm having problems...

I accept that, also that it's correct. So anything above my ADC's 0dbfs level (around 1.339v) will be shown as +dbfs I did know that, and I also realize that it's not making sense what I asked as an option for REW. Jesper.

Hi... A ran some test, to try the two different calibration techniques out. All test is with Victors 998Hz oscillator @ 2.1V sine. The Notch is the Cosmos APU adjusted to -41dB / 998Hz. I carefully calibrated the voltage levels in REW before I started the test's. I'am in no doubt, that I would...

This is really great... After some hour's with trial and error I finally got it right. (Notch is dual fliege OPA1662) This is the way I did it for the result's (see pictures for better explanation) : 1. Adjust Analysis. 2. Take measurement with notch and without notch. (-25dB - Full input...