@Croing The problem appears to be that you uploaded a Blurry image from the start. If you upload a Blurry image then it will show up that way regardless of the theme you’re using. If you take a look at the link to your logo directly, you’ll see it’s blurry here – http://agratzerpianos.com.ar/wp-content/uploads/2017/02/cropped-otro-logo.png
You’ll want to upload a more clearer version of your logo if you have one.
The logo that is shown on your site (with the theme) is smaller than it’s actual size http://agratzerpianos.com.ar A logo/image usually doesn’t become blurry when it shrinks in size from a theme, that only happens when it’s being stretched past it’s original size to appear larger.
So if you upload a clear/non blurry version of your image then it will show up better.
If you want your image to show up as a different size (smaller or larger) this can be adjusted in your CSS. First upload the new version and if you want to increase or decrease the size I’ll help you out.
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