What is causing my HF roll off?

[ThELiZ]

I can't figure out why I'm having such extreme HF rolloff on my Wharfedale Lintons. The below is a plot from REW from my PEQ settings in Roon. I'm only EQing under 500Hz. I get the same result with EQ off. I also get the same rolloff with the mic at 1m from each speaker. Could it be my amplifier?

 

[Sokel]

You better describe your whole chain,including the measuring mic,etc.

 

[ThELiZ]

Onkyo A9010 amplifier
Raspberry Pi DAC (can’t remember which one, but it measured well)
Wharfedale Linton Heritage speakers
Dayton UMM-6 Mic with cal file

 

[staticV3]

Try using REW as tone generator. Same response->it's not Roon.

Try a different mic (e.g. iPhone with HouseCurve). Same response->it's not the mic.

Try a different Amp. Same response->it's not the Amp.

Using this method, you can rule out possible culprits piece by piece.

 

[ThELiZ]

Thanks. Will give that a try

 

[digitalfrost]

Is the mic capsule at tweeter height when you measure?

 

[ThELiZ]

Yes, mic is at tweeter height. Moving the mic around doesn’t change the roll off

 

[Purité Audio]

Do you have another pair of speakers to compare?
Keith

 

[ThELiZ]

I’ve just ran HouseCurve on my iPhone. Seems to show the same issue. This is bypassing my DAC and Roon. Using the built in DAC of the amp.

FYI, the <500Hz changes from this plot are different from my ones above as no eq is being applied

I don’t have any other speakers to try. At this point I can only think it’s the amp or the speakers. Is it possible for both tweeters to show the same issue?

 

[ThELiZ]

In my previous above post, the measurement is at MLP.

Here is the plot from 1m… Maybe it is my mic. I’ll try running my UMM-6 mic from 1m again and see what I get

 

[Thomas_A]

You need to measure with gating.

 

[Talisman]

Onkyo A9010 amplifier

Small off topic, for me that amplifier is one of the best values ever in hifi. It has everything you need, a pretty good DAC, tone controls, pure direct, loudness, many inputs, remote control and it cost just 200 euros new. An exceptional product. When I switched from the 9010 to the Cambridge Audio CX61A I didn't notice any difference, I sold the Cambridge and still have the Onkyo.

 

[voodooless]

How about try with the amps “direct” mode?

 

[Deleted member 48726]

How does your room look? What do you have in it (furniture, rugs, blinds etc.) it doesn't exactly make sense to be either the speakers or the amp and you have confirmed that by measuring close to the speakers, which discards both source, amp and speaker. Variables are now; room and mic.

 

[GaryY]

Once I tested 2 cases, mic pointing speaker or celing with the calibration for each case. Not big difference but there was ~2dB gap between measurements at 20kHz.

 

[ThELiZ]

Thanks for all the replies. I'm pretty sure it's the mic/room. Can’t be arsed to do any more playing around today. I need to get out the house!

Will report back once I’ve done some more testing.

 

[Thomas_A]

Thanks for all the replies. I'm pretty sure it's the mic/room. Can’t be arsed to do any more playing around today. I need to get out the house!

Will report back once I’ve done some more testing.

Gated measurement recommended @1 meter.

 

[kejar31]

Are you sure you are using the right calibration file? Looks like a 90 degree measurement without a 90 degree cal file to me.

 

[ThELiZ]

Are you sure you are using the right calibration file? Looks like a 90 degree measurement without a 90 degree cal file to me.

Do you know what... I've never been sure what orientation the UMM-6 should be at. I've tried measurements with it at 0 and 90 and never noticed any differences. For clarity, I run the measurements with the mic pointed to the ceiling

 

[kejar31]

Do you know what... I've never been sure what orientation the UMM-6 should be at. I've tried measurements with it at 0 and 90 and never noticed any differences. For clarity, I run the measurements with the mic pointed to the ceiling

If you are running the mic pointed at the ceiling are you using the 90 degree calibration file? Generally a 90 degree calibration file will lift the freq from 1k up... Take a look the attached picture of the two calibration files for my UMIK-1 mic to see how they impact the end result..

Notice: that the curve you see on this file will be inverted when applied to your measurement.

edit: spelling