[[KeywordSearchInputContent]]

Free Shipping to store or home

  • Guitars

    Top Categories

    1. Electric Guitars
    2. Acoustic Guitars
    3. Acoustic-Electric Guitars
    4. Left-Handed Guitars
    5. Classical Guitars
    6. Ukuleles
    7. Guitar Value Packs
    8. Guitar Accessories
    9. Vintage Guitars

    Related Products

    1. Guitar Amps
    2. Amp Stacks
    3. Pedals & Effects
    4. Strings
    5. Pickups
    6. Tubes
    7. Capos
    8. Cases & Gig Bags
    9. Stands & Hangers
    10. Straps
    11. Picks
    12. Cables
    13. Guitar Wireless System
    14. Folk Instruments
    15. Books & Videos

    Top Brands

    1. Fender
    2. Gibson
    3. Epiphone
    4. Ibanez
    5. Martin
    6. Music Man
    7. Taylor
    8. ESP
    9. PRS
    10. Yamaha
  • Bass

    Top Categories

    1. Electric Bass
    2. Acoustic Bass
    3. Electric Upright Bass
    4. Left-Handed Bass
    5. Electric Bass Value Packs
    6. Bass Accessories

    Related Products

    1. Bass Amps
    2. Pedals & Effects
    3. Strings
    4. Cases & Gig Bags
    5. Stands & Hangers
    6. Straps
    7. Instrument Wireless Systems
    8. Cables
    9. Books & Videos

    Top Brands

    1. Ibanez
    2. Schecter
    3. Fender
    4. Music Man
    5. ESP
    6. Dean
    7. Squier
    8. Gibson
    9. Peavey
    10. Yamaha
  • Drums

    Top Categories

    1. Acoustic Drums & Sets
    2. Electronic Drums & Sets
    3. Snare Drums
    4. Cymbals
    5. MIDI Controllers
    6. Hand Drums & World Percussion
    7. Drum Hardware
    8. Marching Percussion
    9. Concert Percussion
    10. Classroom & Kids
    11. Accessories & Parts

    Related Products

    1. Sticks & Accessories
    2. Heads
    3. Stands & Racks
    4. Cases, Bags & Covers
    5. Drum Mics
    6. Thrones
    7. Drum Amps & Monitors
    8. Drum Software
    9. Books & Videos

    Top Brands

    1. DW
    2. Pearl
    3. Zildjian
    4. Sabian
    5. Tama
    6. Vic Firth
    7. Remo
    8. PDP
    9. Gretsch
    10. Meinl
  • Recording & Software

    Top Categories

    1. Multitrack Recorders
    2. Portable & Field Recorders
    3. Studio Monitors
    4. Studio Mixers
    5. Microphone Preamps
    6. Signal Processors
    7. Disc Duplication
    8. Studio & Recording Packages
    9. Headphones
    10. Furniture & Studio Foam
    11. Stands & Racks
    12. Cables & Snakes

    Related Products

    1. Software & Plugins
    2. Audio Interfaces
    3. MIDI Interfaces
    4. Control Surfaces
    5. Computers
    6. Hard Drives & Storage
    7. Media, Storage & Memory
    8. iOS Devices
    9. Books & Videos
    10. Headphone Amps

    Top Brands

    1. Avid
    2. Apogee
    3. M-Audio
    4. Ableton
    5. KRK
    6. PreSonus
    7. Focusrite
    8. Native Instruments
    9. TASCAM
  • iOS

    Top Categories

    1. iOS Audio/MIDI Interfaces
    2. iOS DJ Gear
    3. iOS Mixers
    4. iOS Keyboards
    5. iOS Microphones
    6. iOS Live Sound
    7. iOS Docks and Speaker Systems
    8. iOS Accessories

    Related Categories

    1. Headphones
    2. Software
    3. Cables and Snakes
    4. Computers and Peripherals
    5. Books and Videos

    Top Brands

    1. AirTurn
    2. Apogee
    3. Apple
    4. Blue
    5. IK Multimedia
    6. Live Wire
    7. Bose
    8. JBL
    9. AKG
    10. Shure
  • Mics & Wireless

    Top Categories

    1. Condenser Microphones
    2. Dynamic Microphones
    3. Ribbon Microphones
    4. USB Microphones
    5. iOS Microphones
    6. Drum Microphones
    7. Stands & Booms
    8. Mic Cases
    9. Cables
    10. Shockmounts
    11. Windscreens
    12. Books & Videos

    Related Products

    1. Handheld Wireless Mic Systems
    2. Headset Wireless Mic Systems
    3. Lavalier Wireless Mic Systems
    4. Microphone Packs & Kits
    5. Microphone Accessories
    6. Cases & Racks

    Top Brands

    1. Shure
    2. Sennheiser
    3. AKG
    4. Audio-Technica
    5. Blue
    6. Electro-Voice
    7. Audix
    8. Apogee
    9. Neumann
    10. Sterling
  • Keyboards & MIDI

    Top Categories

    1. Production & Groove Machines
    2. Workstations
    3. Synthesizers
    4. Digital Pianos
    5. Portable & Arranger Keyboards
    6. MIDI Controllers
    7. MIDI Interfaces
    8. iOS Keyboards
    9. Keyboard Accessories & Parts
    10. Software & Virtual Instruments

    Related Products

    1. Keyboard Amps & Monitors
    2. Benches & Stools
    3. Stands & Racks
    4. Keyboard Pedals
    5. Cases & Gig Bags
    6. Cables
    7. Power Supplies
    8. Accordions
    9. Books & Videos

    Top Brands

    1. Korg
    2. Casio
    3. Yamaha
    4. Roland
    5. Akai
    6. M-Audio
    7. Moog
    8. Nord
    9. Native Instruments
    10. Dave Smith Instruments
  • Live Sound

    Top categories

    1. PA Systems
    2. PA Speakers
    3. PA Subwoofers
    4. PA Monitors
    5. Power Amps
    6. Signal Processors
    7. Mixers
    8. Microphones & Wireless Systems
    9. Headphones
    10. Power Conditioners

    Related Products

    1. Stands & Racks
    2. Cases
    3. Cables & Snakes & Stage Boxes
    4. PA Replacement Speakers & Parts
    5. Stage Accessories
    6. Direct Boxes
    7. Stage Lighting & Effects
    8. Power and Batteries
    9. Books & Videos

    Top Brands

    1. JBL
    2. QSC
    3. Mackie
    4. Electro-Voice
    5. Bose
    6. Harbinger
    7. Shure
    8. Yamaha
    9. Allen & Heath
    10. Souncraft
  • DJ & Lighting

    Top Categories

    1. Controllers & Interfaces
    2. DJ CD, MP3 & Media Players
    3. DJ Mixers
    4. DJ Software
    5. Production & Groove
    6. Turntables
    7. iOS DJ Gear
    8. Packages/Systems
    9. DJ Accessories
    10. DJ Headphones
    11. Karaoke
    12. Cables & Snakes
    13. Stands & Racks
    14. Cases & Bags

    Related Products

    1. Lighting & Effects
    2. Intelligent Lighting
    3. Color Changers & Wash Lights
    4. Par Cans
    5. Lasers & Strobes
    6. Fog, Bubble & Snow Effects
    7. Lighting Controllers & Dimmer Packs
    8. Mirror Balls
    9. Gels, Gobos & Lenses
    10. Lighting & Effects Packages
    11. Lighting Stands & Truss
    12. Books & Videos

    Top Brands

    1. Pioneer
    2. Native Instruments
    3. Numark
    4. Rane
    5. Denon
    6. VocoPro
    7. Stanton
    8. Chauvet
    9. American DJ
  • Accessories

    Top Categories

    1. Guitar Accessories
    2. Bass Accessories
    3. Strings
    4. Tubes
    5. Pickups
    6. Tuners & Metronomes
    7. Stands & Racks
    8. Cables & Snakes
    9. Cases & Gig Bags
    10. Care & Cleaning
    11. Picks
    12. Practice & Performance Aids
    13. Books & Videos

    Related Products

    1. Recording Accessories
    2. Keyboard Accessories
    3. Live Sound Accessories
    4. DJ Accessories
    5. Lighting Accessories
    6. Furniture & Studio Foam
    7. Software & Virtual Instruments
    8. Books & Videos
    9. Harmonicas

    Top Brands

    1. D'Addario
    2. Ernie Ball
    3. Dunlop
    4. ProLine
    5. Live Wire
    6. Hercules
    7. Levy's
    8. EMG
  • Band & Orchestra

    Top Categories

    1. Woodwind Instruments
    2. Brass Instruments
    3. Orchestral Strings
    4. Marching Band
    5. Concert Percussion
    6. Classroom and Kids

    Related Categories

    1. Woodwind Accessories
    2. Brass Accessories
    3. Orchestral Strings Accessories
    4. Marching Band Accessories
    5. Concert Percussion Accessories
    6. Books, Sheet Music & Media
    7. Tuners & Metronomes

    Top Brands

    1. Vandoren
    2. Yamaha
    3. Rico Reeds
    4. Buffet Crampon
    5. Bach
    6. Selmer Paris
    7. Denis Wick
    8. Kanstul
    9. Jupiter
    10. Getzen

Item # 101979912 | Customer Ratings: Ratings ( 5 Based on 2 reviews)

Print this page

  1. Select the information you'd like to print out.
  2. Cancel
Groove Tubes SAG-AX7-MPI Matched Phase Inverter Tube Changing Kit
Use Add to Cart below to have it shipped to you, or to a store near you.
Close
  • Store
  • Availability
Guaranteed Lowest Price
Pickup In Store
GC Shopping Cart
 Cart Contents
Qty Description Price Shipping Subtotal 
      Groove Tubes SAG-AX7-MPI Matched Phase Inverter Tube Changing Kit (101979912)
Availability:  


The Groove Tubes SAG-AX7-MPI Matched Phase Inverter Tube Changing Kit consists of specially selected and matched 12AX7 vacuum tubes for critical audio or guitar/bass amplifier use. They're intended primarily for matching the two sides of the triode for phase inverter or driver use.

The Groove Tubes AX7 tube is a dual triode where the A and B sides are closely matched for use in critical high end audio applications or for use in the phase inverter or driver position of musical instrument amplifiers.

The benefit of this tube in a guitar or bass amplifier is a matched output section. At lower frequencies such as dropped tunings, 7 string guitars, or bass guitars, the upper and lower portions of the output waveform will be much more equal. When this waveform is not equal, differences are cancelled out in the NFB loop of class A/B amplifiers and are noticed as a lack of sustain or apparent "dead spots" in areas of the fret board.

At high levels at all frequencies, sustain will be improved. This is even more critical in Class A amplifiers such as the Vox AC-30 and Matchless amplifiers.

Use this MPI in any application where a phase inverter / driver of the ECC83/12AX7/7025 tube is specified. The phase inverter / driver position of a guitar or bass amp is a current driving position, and not part of the tone generation stage. These tubes are selected for specific characteristics, so may be a 12AX7R, 12AX7C, 12AX7M or another 12AX7 type that has been selected for specific curve traces as the objective. One can not specify the tube type desired.

If you want a specific type matched as an MPI you need to order the tube and then add the SAG labor charge on top of the tube. The stocked MPIs are generally made from 12AX7C, 12AX7R (WC and NOT WA) and the new 12AX7M. Any of these tubes may be supplied as they are matched for specs and vacuum tube curve traces and not for tube type.

Use of a 12AT7 in place of a 12AX7 will yield more clean headroom in your output section. The two tube types are interchangable without any adjustment required, so feel free to experiment!

Please contact GT SAG directly if you have any questions or specific application requirements.

Country of origin: China

Groove Tubes SAG-AX7-MPI Matched Phase Inverter Tube Changing Kit Features:

  • Country of origin: China


Groove Tubes SAG-AX7-MPI Matched Phase Inverter Tube Changing Kit Specifications:

  • Country of origin: China


Groove Tubes SAG-AX7-MPI Matched Phase Inverter Tube Changing Kit

90 day warranty on power tubes, includes replacement of whole set if one tube goes bad.
180 day warranty for preamp tubes.
3 year warranty on SubstiTubes and Solid State Rectifier.
Check with M-Audio for warranty on GT microphones.

Get your gear covered!

Now you can get added warranty protection for your new gear. Pro Coverage steps in where the manufacturer's "normal wear and tear" ends. Our PRO COVERAGE program offers you UPGRADED COVERAGE if your product ever fails!

Pro Coverage includes:

  • Accidental damage protection (new gear only)
  • Expedited Repair
  • Free Shipping (for returns or repairs)
  • 100% Coverage for Commercial Use
  • Extended Return Period
  • Extended Price Protection
  • No Lemon Guarantee
  • Free Transfer of Coverage to a new owner
  • Repair Costs Covered for up to 3 years from date of purchase
  • Repairs Can Be Authorized Toll-Free by Phone or the via the web
Product Reviews
(Based on 2 reviews)
Sort reviews:
Viewing Reviews 1 - 2 of 2
  • groove tubes sag ax7 mpi

    As reviewed by j homer johnson on 10/23/2009

    this tube made my carvin nomad's el 84s sing. i questioned the worth of this one tube until i spoke with micheal at groove tubes and read an article from guitaramplifierblueprinting.com that explained the importance of having both plates of the phase inverter tube sending equal voltages to my power section . this tube does what it says it will do. i've got to buy another for my belair

    4 of 5 people found this review helpful.
    Was this review helpful?
  • I never tube an amp without it.

    As reviewed by Maxim on 7/3/2014

    This is my favorite tube to use as a phase inverter in ANY of my amps, whether it be a clean amp, or high gain. I am not a fan of the chinese preamp tubes which this tube is a Sino 12ax7, and nor am I a big fan of Groove Tubes but this one is great. It is very expensive, but I feel that Groove Tubes is the best when it comes to making perfectly balanced phase inverters. This tube really smooths out an amp. There are plenty of big tube stores online that offer phase inverter matching, but none of those big stores have the in house equipment that Groove tubes has to test and match these dual triode tubes as closely as this. Give this thing a try you will most definitely hear the difference.

    0 of 0 people found this review helpful.
    Was this review helpful?
Questions about the SAG-AX7-MPI Matched Phase Inverter Tube Changing Kit (101979912)


To: GuitarCenter.com
PO Box 4769
Westlake Village, CA 91359
USA
866-498-7882
 
Order #: (if applicable)  * Denotes Required Field
*First Name:
*Last Name:
*Email:
Phone:
*Subject:
*Message:
Click to add file attachment
File Upload 5mb limit