Amp Loop Adapter ALA-1

Product code 00872


Most of amps feature the effect loop (FX LOOP) what enables to connect various guitar effect. The signal level varies in different amp models (from 0,3 to 15 Vpp) what can substantially affect the effect tones.


In terms of signal level the guitar effects are grouped as follows:


- designed to work directly with the guitar (for signal from 1 to 2,5 Vpp)


- designed to work on the ‘professional guitar effects’ signal level (4dBV i.e. 4,6Vpp)


- which have the gain adjustment and can work in both mentioned signal ranges


Not matched signal level mostly brings the overdriven sound (sometimes called "sound’s dynamics limitation") and higher hum level. ALA-1 enables precisely ‘matching’ the signal level of connected effects.


Amp Loop Adapter ALA-1


The other problem which occurs especially in older models of tube amps is the high impedance of SEND output. Connecting longer (few meters) cables brings hi tone loss.


Thanks to innovative circuit solution applied in ALA-1 this problem is completely solved.


Additional advantage is only one cable for transmitting SEND and RETURN signal (one ‘from amp to pedalboard’ cable less) which solves the problem of ground loops caused by SEND and RETURN signal cables.


Amp Loop Adapter ALA-1


1 - connector for ALA-1 adapter
2 - GROUND LIFT switch
3 - OUT connector
4 - IN connector


Adaptor can be installed in the rack 19” using the GLAB 1U RMS FRONT PANEL (Product code: 00831). Package contains two Velcro fasteners to fix the device to smooth surfaces.



 Basic features:

  • lossless transmission, with one cable, of SEND and RETURN signals independently from OUT and IN circuits of amp effect loop,
  • possibility to adjust signal level by boosting or attenuating the signal sent to the effects,
  • attenuation module with regulation up to -16 dB (/6),
  • boost module based on A class amp with regulation up to 14 dB (x5),
  • possibility to bypass the boost and attenuation modules,
  • high level of transmitted signal 18 dBu (17Vpp).

Technical parameters:

Dimensions: width 110 mm
depth 65 mm
height 40 mm
Weight: 0,63 kg
Cable length: 6 m
Input impedance: 400 kΩ
Output impedance: 200 Ω
Maximal level of transmitted signal*: 18 dBu (16 dBV, 18 Vpp)

* - with activated attenuation and boost modules
20Hz to 20 kHz @ - 0,35 dB
Power supply 9V DC 50 mA: (8,7 do 9,4V regulated)



Amp Loop Adapter ALA-1 User Manual (458 kB)
CE Declaration of Conformity (173 kB)

Press Releases:

  Testbericht GLAB ALA-1, LMS-1
  Gitarre & Bass 12.2010 (pdf, 679 KB)