HDQTRZ Mastering Studios has been the secret weapon behind record labels for years, creating the best sounding mastered tracks in the music industry. Send us your music and listen for yourself.

Grammy Judge Earle Holder is considered a top Professional Mastering Engineer. He is passionate about insuring your music sounds the absolute best. We specialize in all styles of music including classical, rock, hip hop, jazz, trance, techno, etc.

Hdqtrz Digital Mastering Studio is committed to providing their clients with the best sounding finished product ever. Get a free download of any music contract you need by clicking on our “Tips” link.

Tasteful compression on individual instruments is fine but don’t normalize, compress, limit or eq your stereo mix at the output before you give it to me.

The mixes should not peak over 0 dBFS and if they “look” soft on your editor after the mix-down – DON’T TURN IT UP.

You can send (and receive) your project from anywhere in the world over the internet to Hdqtrz Digital Mastering Studios (we have a high speed line with lots of bandwidth allowing us to download your large .wav or .AIFF mix files.

Our clients benefit from the expertise of seasoned, industry professionals with more than forty years of industry experience.

HDQTRZ Digital Mastering Studios is owned and operated by Grammy Judge Earle Holder, Professional Mastering Engineer, for over twenty years.


See Earle at HDQTRZ Mastering Studio at work

Mastering the track named “Darling Girl” for Tony Terry

Mastering the track named “Pretty” for Tony Terry


Register your interest in HDQTRZ Practical Audio Mastering Workshop. LEARN MORE HERE

We specialize in the following Genres of Music

  • Alternative Music
  • Blues
  • Classical Music
  • Country Music
  • Dance Music
  • Easy Listening
  • Electronic Music
  • European Music (Folk / Pop)
  • Hardcore Punk
  • Heavy Metal
  • Hip Hop / Rap
  • Indie Pop
  • Inspirational (incl. Gospel)
  •  Asian Pop (J-Pop, K-pop)
  • Jazz
  • Latin Music
  • New Age
  • Opera
  • Pop (Popular music)
  • R&B / Soul
  • Reggae
  • Rock
  • Singer / Songwriter (inc; Folk)
  • World Music / Beats

  • Grammy Judge Earle Holder is an award winning and amazing professional. His masters are phenomenal and his skill reaches across many genres. If you've got a project, check him out.Chuck McDowell, ESOEBO - eclectic selections of everything but opera

  • For all my music buddies. This is one guy you can't go wrong with. He's a good friend and is someone you can count on to go the extra mile. Just ask Lynn. Last Saturday night Earle and I were up in our two studios working on one of my songs until well after midnight and it was me who finally said we better call it a night. In this music business you run into all kinds of folks, some working an angle, some barely working and some who are true to the art and to those they take under their wing. My friend Earle is as true as they come and one of my most cherished music friends. If you need mastering work or just advice, you won't be sorry. You mean a lot to me Earle. Just want you to know thatOwen Poteat

  • I recently put on a huge vocal showcase which featured 23 of my artists. I was in search of someone who could take my production from 0 to topnotch , so I contacted Earle at Hdqtrz…. Talk about impeccable sound quality !! Earle mastered each song to perfection. He put that extra something special on it that seamlessly flowed from one song to the next !! If you desire a professionally enhanced improvement to your production, contact Grammy Judge Earle Holder at Hdqtrz Studios. He has the ability to take your creations to the next level !!Tameko’Star a.k.a. Livin’ joy International MCA Recording Artist

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  • Not only is HDQTRZ Mastering efficient and professional, their mastering techniques provide the best results time and time again. Grammy Judge Earle Holder and I have worked extensively on a number of projects and his work at HDQTRZ continually impresses me. I won’t have my music mastered anywhere else.C-Doc (The WarHammer) Artist, Producer The Impossebulls, Public Enemy

  • Thank god for Grammy Judge Earle Holder! He brings my mixes to life and is a pleasure to work with. There was a time when I was studying to be a mastering engineer but realized as long as Earle was still doing it, I’d give my mixes the best possible treatment. His knowledge and passion put him at the top of my list.Charley mac

  • I am so happy about the work that has been done for me by Hdqtrz. They are fast, dependable and provide excellent work. With these qualities I am sure to use their services over and over again. Thanks so much HDQTRZ!Adrianna Costello

  • I’ve had Earle master tracks, that had been rejected by our artist from other mastering studios. And every time I’ve used Grammy Judge Earle Holder’s HDQTRZ Mastering service, my projects were one fast, with great communication and results were spot on. We highly recommend Earle at HDQTRZ Mastering.Ralph Cavallaro, Founder & CEO, Organic Music, LLC, Woodland Hills, California