Oh man, I wish I had listened to the AH-D1001 when I had the chance. Still, I'm glad you were able to testify and cross reference both headphones. Both the AH-D1001 and the modded P-100 headphones are great!
I think after burning in for about 5 hours, the Elise amp was very warm sounding. It complements with the HD650 very well because the highs were rolled off. When listening to the HP100, I remember hearing a fuller sound especially in the mids and the highs. The bass turns out slightly more U-shaped than my SS amp.
Thank you @DecentLevi for letting me check out your gear! It's been great listening to the modded HP-100 and the Elise amp.
Even though I had about 15 minutes to audition the modded HP-100, I'll do my best to describe its revamped sonic signature. I used Levi's source and brought my Luxman P-1 headphone amp as my reference audio gear.
The bass is definitely V-shaped. The drum snares are considerably quick in recovery.
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