“Best tube I've used in the Bottlehead Crack! Better soundstage and bass slam and extension compared to the Mullard. Comparable highs to the stock RCA's. Slightly more forward mids compared to both. Now my daily driver...”

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Posted 8 years ago

“Running these in a Primaluna Dialogue Hp integrated and love them. They have great bass, phenomenal midrange and a nice layed back top end. They through a nice wide soundstage and sound great with classic rock, singer song writer music. Very impressed.”

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Posted 8 years ago

“The Brimar CV4003 is one of my favorite driver tubes for the Bottlehead Crack OTL headphone amplifier. It brings to mind the story of Goldilocks. Highs, Lows, and Mids all sound “just right” no matter the musical genre.”

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Posted 8 years ago

“These are great tubes for adding texture, layers of resolution and musical inner details to the sound while not being too warm, analytical or etched. I was looking for some more depth and richness upon switching my stereo to featuring a solid state amp after using a KT88 based tube amp. I didn't know about Brimar and took Kevin's advice to try them in my PrimaLuna cd player. After hearing how wonderful they sound, I purchased six more to use with my PL Premium Dialogue Preamp. I have to admit this tube rolling stuff is a dramatic and significant part of the performance and ability of tube gear to be fine tuned and sound so excellent. The differences are easily heard especially with PL gear that starts out with such a good design. I'm a professional musician and member of the Philadelphia Orchestra for over 35 years. These tubes balance and integrate the sound of my equipment and bring me several shades closer to the realistic sense and illusion of hearing live musicians. Getting tubes of this quality is like when a wind musician finds a great mouthpiece or a string player finds a bow that lets their instrument sound better and enables them to perform music at a higher level. I'm enjoying vocal lines by hearing greater clarity and enunciation from singers. The instrumental harmonies and string sections are more easily heard with the distinction of the ensemble sizes showing in the soundstage. The violins, violas, cellos and bassi are no longer just a mass of strings but can be heard within their sections, space and depth of the hall. The timbre of the instruments have the same color as in life. These tubes are real winners for me! Equipment in use: Daniel D'Agostino Master Power Classic Stereo Amplifier Bob Carver Cherry 180 amplifier PrimaLuna Premium CD Player PrimaLuna DiaLogue Premium Preamplifier VPI Prime turntable Manley Chinook phonostage JL Audio e112 Subs Magnepan 20.7 speakers speaker, interconnect, and power cables by Kubala-Sosna”

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Posted 8 years ago

“The best 12AU7 I have ever used, and I have them all including Telefunken (over rated) a few different types of Mullards, Siemens, Amperex Bugle Boys, I even have some crazy Siemens ECC802S. What I like about this tube is there is nothing to NOT like. It doesn't do anything wrong. It's the most "centered" without coloring the top end to make it too tizzy or too dark. I will also say here that it is VERY quiet. I have four products that use 12AU7's, and one of them is an old pre made by Conrad Johnson, the PV-12A. That preamp is a problem as it has so much gain and tubes are noisy or microphonic. This tube is SCARY quiet. My current reference preamp is the excellent PrimaLuna DiaLogue Premium, which has outclassed even my Audio Research REF 5. I put a pair of these in one position, then right to the rear a pair of Cifte's for added detail and to tweek up the highs just a teeny bit. I heard for a first time a Doors song that I know so well only to hear there was a very very quiet overdub of Jim Morrison's voice in the background. All of this due to picking out the quietest preamp and tubes and dropping noise floor lower and lower. What a journey.”

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Posted 8 years ago

Denny Parker, CO

Unverified Reviewer

“Running these in my PL Dialogue Premium HP Integrated with KT120 power tubes. With the extra headroom provided by the KT120's I can run this amp in triode mode most of the time now. In this mode the Brimars impart a very refined and naturally textured sound. Piano has wonderful tones and overtones while sounding full and dynamic up and down the frequency scale, and violins are sweet and shimmering. Vocals take on a very natural quality. Also, they seem to take some of the bite out of ultralinear mode - on some recordings makes it hard to decide my preferred setting. Highly recommended.”

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Posted 8 years ago

“I've tried many different 12AU7 NOS tubes and these Brimar 12AU7/CV4003's add textures to my high resolution classical music (especially on string instruments) that I've never hear before. They also seem to smooth out subtle timing queue's making the music more engaging. Great valves. Highly recommended!”

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Posted 9 years ago

Brimar CV4003 / 12AU7 Platinum Grade / No Cryo Reviews