# High End RME HDSP 9632 Sound Card Gives Strange Calibration Readings; Can Anyone Help?



## marsx (Feb 16, 2010)

Hi all,

I have two sound cards, an fairly expensive RME HDSP 9632, which is a pretty high end PCI sound card made by a German Company called RME and an inexpensive external USB Sound card, the M-Audio Fast Track Pro. With the M-Audio, I got an almost perfectlly flat response with a drop off around 20,000 khz, which was great.

However, when I tested my main card, which has much higher specs on the D/A and A/D converters and is very basic but high end, I got a very strange reading every time I did the test. Instead of the flat response the other card gave me, this card gave me the following:

1) From about 3Hz to 200Hz it started at 0 and then went up slowly to 5 db at about halfway to 200Hz and then back down to 0 at 200. Then it got wierder. From 200Hz all the way up to 20,000Khz, it curved up and down like a sine wave between 0 and 4-5 db all the way from 200 to 20,000 with the peaks getting closer and closer the higer the frequency until they were smashed together at 20,000. There seemed to be a rough total of 50 or so sine-like curves between 0 and 5dbs all the way up.

Just to let you know, the trace adjustment on both cards was set to "none." I noticed with the RME, that when I change the trace adjustment setting to 1/1, the the response graph was almost flat from 20 to 20,000, except with a slight bump at around 600Hz. 

Has anyone had a sound card give them a strange reading anything like this. Does anyone have any ideas what settings I might have wrong? The RME's software interface and Mixer is much more sophisticated than the M-Audio's (the first card I tested) and there are a lot of settings that may impact the outcome. I wrote to RME and told them what happened and they couldn't tell me just from the data, they wanted to see the graph, but I couldn't find a way to print the graph; so another question I have is, does anyone know how to print the calibration graphs from within Room EQ Wizard or how to export them to print them another way? I found that CTRL-P did not work within the Room EQ Wizard software.

By the way, I'm using Windows 7 64-bit, and Room EQ Wizard works fine on it. As I said, I have the two audio cards, but I primarily use the RME. I actually tested the RME first because I keep the other card disabled except when I need to do something in Pro Tools. I only tested the M-Audio because I wanted to see if it would give me different readings than my RME and, as I said, it gave perfectly flat readings. But there are no sophisticated settings in a Software Control Panel and Mixer as there are in the RME. 

Any ideas anyone? I can always test the room with the M-Audio, but the response of my higher quality card concerns me and I don't want to record with it if there is a problem with it. If no one has any experience in this forum, my best bet is to send the graphs to the manufacturer, but as I said, I can't figure a way to print them, so if anyone can even help me just figure out how to do that, I would be most grateful.

Any help or ideas would be greatly appreciated.

Sincerely,
marsx


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## JohnM (Apr 11, 2006)

That type of response is caused by a feedback loop, either caused by a monitoring feature in the soundcard that needs to be turned off in the soundcard's mixer software or by not having the line in muted in the playback mixer.


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## marsx (Feb 16, 2010)

Hi,

Thanks, I got a more flat reading but I am still concerned about this REW software. When I finally got all the settings right and got a reading, the RME HDSP 9632 (which is considered a fairly high end card) gave me a consitent reading that showed from 15,000 khz to 20,000 the dbs went consistently down over that frequency range on a curve ending at about 0.8 dbs below 0; For 40 hz to 15,000khz it was flat. However, my low cost M-Audio Fast track Pro was completely flat from 80 hz to 20,000khz. I wrote to support at RME and told them what I was experiencing and they put the software I was using (REW) into question and told me I should try some software called RMAA, which is specifically for testing sound cards. When i tested the card in that software (the RMAA software is free and is the standard for testing lo and hi end gear of all types), my card showed a completely flat frequency response. Anyone ever have a card that had a less than flat frequency response with RME? Anyone test the same card using RMAA software to confirm if there was a problem with their card? Now that I have found a discrepancy between the REW software, which is freeware and offers no warranty of reliability, and the RMAA software, which is kind of like the standard software that many manufacturers use to rate their equipment, I'm concerned about the accuracy of the REW software all around.

Anyone have any suggestions?

Sincerely,
marsx


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## JohnM (Apr 11, 2006)

REW runs the card at either 44.1kHz or 48kHz, depending on the selection in the soundcard settings, and 16 bit. Try RMAA at the same sample rate. REW's access to the soundcard is through Java's built-in sound classes, which in turn use the WDM drivers. The plot you see is the result of the data the soundcard drivers provide, REW does not alter it. It has been verified against a variety of packages, both free and commercial (including RMAA), and produces the same results when the soundcard is run with the same settings.


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## marsx (Feb 16, 2010)

Hi,

I am baffled. When I tested it, making sure the card is set at 16 bit and 44,100khz and the levels are good, I get a flat response until 15,0000khz at which point the graph starts to slowly curve down so that by the time it reaches 20,000khz, it is off by about .8db. When I test the same card in the free version of RMAA, which tests using WDM drivers (unless you buy the pro version to test ASIO, but I used free version), the program showed that the card gave a completely flat frequency response from 4hz to 22,000khz, i.e., a different response than the REW readings. However, I tested my Yet, my M-Audio Fast Track Pro in both REW and RMAA and got a flat frequency response in both programs. Any ideas about why I would get a different reading from REW than I get from RMAA only on one card? (FYI, I used the same settings on each card for both programs.)

I look forward to hearing from you.

Sincerely,
Wade (marsx)


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## JohnM (Apr 11, 2006)

Sounds like a soundcard configuration effect to me. REW doesn't make any attempt to force the soundcard setup, it just requests data at the sample rate and bit depth it has been set to. The card may actually be running at a different rate and/or bit depth and REW (or other applications) may be fed data that has been resampled or truncated either within the card or in the OS. As an example, here is a set of plots from an SB Live, with REW left on the same settings for all 3 but the soundcard setup changed via its own app. This doesn't mean there is anything wrong with the card, it's just how the audio interfaces and drivers work.


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## marsx (Feb 16, 2010)

The readout of my RME HDSP 9632 frequency response shows up this way with every setting I could think of trying. I even installed it in another computer, but it didn't change the reading. I've also tried measuring the card with the RMAA6 software and can't get a readout because of errors; either there is clipping or the signal is to low and no matter how delicately I adjust the RME mixer, I can't get a complete reading without errors. Here is a picture of the reading I get from my RME card:










Also, for the life of me, I can't get RMAA to give me a graph at all with the same settings that produced this graph is REW.


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## marsx (Feb 16, 2010)

I notice that with all three different settings of your SB Live card, the frequency response begins dropping at about 7,000khz. Do you find this an acceptable response. I don't know about your card, but my RME HDSP 9632 is considered a high end card and should give a flat frequency response from 20hz to 20,000khz and mine also drops off at about 7,000khz. Is that REW causing that? I found that with my M-Audio card, which is about a 1/4 of the price of my RME card, I get a flat frequency response in REW from 20-20,000; without any fall off from 0 db starting at 7,000 like in your graphs and in the graph of my RME. Is that telling me my M-Audio has a better frequency response than my RME, or do you think it could be due to settings inside my RME Mixer?

Look forward to your response.


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## jean (Aug 31, 2009)

marsx said:


> The readout of my RME HDSP 9632 frequency response shows up this way with every setting I could think of trying. I even installed it in another computer, but it didn't change the reading. I've also tried measuring the card with the RMAA6 software and can't get a readout because of errors; either there is clipping or the signal is to low and no matter how delicately I adjust the RME mixer, I can't get a complete reading without errors. Here is a picture of the reading I get from my RME card:
> 
> 
> 
> ...


Hello,
i wouldn't be bothered with a 0.5 db fall at 20000hz, compared with the peaks and valleys of speakers and room responses and i don't mention the ears of the listeners. When you make your measurements with a 5 db scale you don't even need to use the card calibration file. I think your card is perfect.
Jean


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