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API TranZformer LX Multi-Effects Footpedal

Guitar Pedal and DI Box


Special 12-Month No-Interest Financing.

SKU: APILXBassTranZformer Categories: , Brand:


The API TranZformer LX is a foot pedal optimized to give your bass the distinctive API sound onstage or as a recording DI

One of the most famous bass sounds that came out of the best studios of the 70s, such as Sunset Sound, was the low-end growl that came from the steel-wound transformers from their custom API console. Of course, API EQ and compression played a significant role in shaping the sound of bass. Of course, rather than an expensive rack of gear or a six-figure API console, you can have that sound in a far more affordable effects pedal. The TranZformer LX comprises an API 525 feedback-style compressor, and inductor-based 3-band equalizer derived from the classic API 553 program equalizer, and of course, the aforementioned transformer output for that signature API sound.

API TranZformer LX in one take:

  • Traditional fully discrete API circuit design
  • Variable compressor with in/out switching
  • 3-Band +/-15dB equalizer with in/out switching
  • Input Gain control with +30dB gain
  • Balanced and unbalanced output phase reverse
  • Balanced output ground lift
  • Included 18-volt external power supply optimizes performance
  • Hardwire bypass switch
  • Universal +18VDC power supply
  • LED clip indicators input and output stage clipping
  • Five-year parts and labor warranty


 The signal path of the TranZformer LX from input is gain, compressor, EQ, and transformer output. Like the studio gear it derives its sound and functionality from, the TranZformer LX includes phase reversal switches on each output, ground lift, clip indicator, transformer output, and a hardwire bypass switch. The input gain level is +9dB to +30dB and interacts with the compressor, increasing compression as gain increases (much like some famous studio compressors).

The equalizer is a 3-band peaking design with ±15dB gain. Its three corner frequencies are set at 100Hz for body, warmth, and depth; 400Hz for body, warmth, and power; and 2kHz for presence, attack, and articulation. TranZformer LX’s output is –inf (full off) to 0dB, which sets the output level for the unbalanced 1/4″ output, which feeds your guitar amp. The balanced output is fixed. The compressor has six switchable settings): 1 = subtle compression, 6 = maximum compression. Turning clockwise Increases gain reduction (lower threshold) while simultaneously raising output level to match.

Both the compressor and equalizer are able to be switched in and out independently. The TranZformer LX is built to API’s exacting standards and comes with all of the features you’d expect in their studio gear, including phase reverse on each output, ground lift, clip indicator, true bypass, and of course, the unmistakable API sound.


The controls of the TranZformer LX are in the style of API’s studio gear. They include:

  • Gain: Input level; +9dB to +30dB; More gain creates more compression
  • Comp (compression): Determines amount of compression (gain-reduction); Higher
  • numbers provide more compression (lower threshold)
  • Clip LED: Illuminates to indicate Input Gain or Output stage (pre Level) clipping
  • Tone
  • Output Level: -inf. to 0dB attenuator; 0db (no cut) is fully clockwise
  • Sets level for 1⁄4” unbalanced output only (balanced output level is fixed)


  • Comp (compressor): Engage/disengage compressor; lit LED when engaged
  • Tone (equalizer): Engage/disengage equalizer; lit LED when engaged
  • Bypass: Hardwired unbalanced bypass; lit LED when bypassed


  • Instrument Input: 1⁄4″ Hi-Z, unbalanced
  • Unbalanced output (to amp): 1⁄4″ Hi-Z (fed directly from input in bypass)
  • Balanced Output: 3-pin XLR male, Lo-Z line level (XLR is muted in bypass)
  • 18 Volt DC power input (on back) 500mA maximum
  • 1mm x 5.5mm barrel connector, tip negative


  • Unbalanced output phase reverse (inverts unbalanced output polarity)
  • Balanced output phase revers (inverts balanced output polarity)
  • Output ground lift (eliminates hum from ground loops)

 With the API TranZformer LX multi-effects pedal, you don’t have to wait until you get to the studio to add API mojo to your bass. For more information, call or chat online with your Westlake Pro Sales Consultant today.


 API TranZformer LX specifications:

  • Input connection: 1/4″ Hi-Z unbalanced instrument input
  • Input Impedance: ~500kΩ
  • Maximum Hi-Z instrument input level before clipping: +13dBu
  • Output connections: 1/4″ Hi-Z unbalanced output w/ variable level control,
  • XLR Male balanced line output, fixed level (Balanced line output level is +6dB higher than Hi-Z output with Level control fully clockwise)
  • Output Impedance: Hi-Z output: 7.5k ohm
  • Balanced Line output: Less than 75 ohm
  • Gain Control: 9.2dB – 30dB, Variable, Hi-Z output
  • 2dB – 36dB, Variable, Balanced line output
  • Level Control: -inf. to 0dB, Variable, Hi-Z output only
  • Maximum output level before clipping: Hi-Z Output: +21dBu
  • Balanced Line Out: +27dBu
  • Frequency Response: +0, -0.5, 20-20kHz, both outputs, low-capacitance cable
  • Noise: -75dBu
  • THD+N: Less than 0.01%
  • Tone Control: 100Hz, 400Hz, 2kHz peaking, continuously-variable boost/cut, +/-16dB range
  • Compressor: Ratio: Varies from 2:1 to 20:1 depending on compressor control setting
  • Attack (fixed): Less than 5ms
  • Release (fixed): 100ms average (frequency-dependent for natural envelope tracking)
  • Power Supply: 18VAC @ 1A
  • Size: 8″ x 5-1/2″ x 4″
  • Size (Boxed for Shipping): 10″ x 8″ x 8″
  • Actual Weight: 4 lb.
  • Shipping Weight: 6lb.

Additional information

Weight 4 lbs
Dimensions 6 × 8 × 4 in
Manufacturer Part Number

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