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Effectrode LA-1A Leveling Amplifier Review

I'm just going to come right out and say it. If you loved the Effectrode PC-2A I think you'll absolutely love it's big brother, the LA-1A.


This thing rocks and is super quiet. In fact, it is probably the quietest compressor I have ever used.



With the LA-1A Effectrode employed a parallel tube plate design and they claim the LA-1A is "technically the quietest pedal or studio leveling amplifier ever made”. This tube plate design is the type of tube circuitry only ever found in high-end tube phono preamp stages for turntables. According to Effectrode,


Parallel tube design minimises the noise floor and maximises the signal to noise ratio of your instrument. It’s an expensive way of achieving noise reduction, as four identical input tube stages are required, however it yields stellar tone quality without the compromise of noise gates or ‘cutting’ certain frequencies with equalisation. The parallel tube design has never been built into a stompbox or even a professional studio leveling amplifier/compressor before, making the LA-1A something truely special.

I can't confirm any of this, but I can't deny it either. The Effectrode LA-1A Leveling Amplifier is remarkably quiet.

Let's talk dials and switches here. There are 5 knobs and two switches.



The Peak Reduction knob sets both the threshold and the amount of signal compression. As the knob is rotated clockwise the volume level of loud notes is reduced relative to quieter ones, squashing playing dynamics. The effect becomes greater. This Peak Reduction reacts basically the same way as the Peak Reduction knob on the PC-2A. If you've used that compressor before, the way the dial responds on the LA-1A will be familiar. There is plenty of compression on tap and at higher settings it does get pretty squishy. That said, I don't think it makes the best limiter. It feels more natural at mid to lower compression settings.

The Gain knob adjusts the ‘make-up gain’ and is used to match the relative levels of bypassed and effected signal. Effectrode says it can also provide +15dBu of tube boost when the ‘Peak Reduction’ knob fully counterclockwise (zero compression). Compared to my PC-2A there is not as much audible gain. Even though Effectrode says the PC-2A provides +15dBu, the PC-2A sounds louder with the gain dimed. I don't think it is my ear playing tricks on me either. There is a noticeable difference in volume. That said, I don't know why anybody would need more gain than the LA-1A provides — even at higher compression settings.

Boost knob gives an additional +6dB of gain (on top of the make up gain) – this is useful when soloing on guitar or bass and can push the input stage of a tube amp into overdrive very nicely too. The Boost footswitch engages (red LED lit) and bypasses (green LED lit) the boost. Here's the thing with this boost though. There is a slight delay when activating the boost via foot switch. It sill let you down if you expect an instantaneous boost effect. It's about "one-one thousand" delay after stomping the boost switch. Still, I liked using it for a little extra "umph" on a chorus or bridge to bring out a little more volume. The boost is clean as the LA-1A doesn't really ever breakup. There is tons of headroom.

Attack and Knee knobs allow the compression character to be further tailored. While later versions of the PC-2A had small dials inside the enclosure to adjust attack and knee, the LA-1A puts these dials on the top — easy to use. Rotating the ‘Attack’ knob clockwise increases how fast compression kicks in. The entire range is useful. My sweet spot was about 9:00 for a slowish attack allowing some of that initial transient (or punch) through. The Knee knob alters the input/output curve, i.e. how the LA-1A transitions into compression – rotate clockwise and the LA-1A compressor effect to be more obvious and counter-clockwise for smoother, more subtle compression effect. To be honest, I'm not sure which way I like better. All the way counter-clockwise and clockwise both sound great. I tend to prefer smoother compression... but the hard knee (more clockwise) really sounds great. I compromised and put the dial straight up as my point of preference.

The Dynamic EQ switch is essentially a treble boost to restore some bite that can feel attenuated under higher compression. With the ‘Peak Reduction’ knob fully counter-clockwise (zero compression) dynamic eq is inactive, however as the knob is rotated clockwise, and the pedal begins compressing, the effect becomes increasingly pronounced. I was skeptical about the value of this switch for bass but am a convert. Especially when using a darker bass and higher compression.


That treble boost effect is quite subtle but really makes a darker bass feel more punchy.



The Bypass footswitch is true bypass and utilizes quiet true bypass switching to minimize ‘pops’ or ‘thump’ when engaging the pedal and ensure there is no loss of guitar tone when the pedal is bypassed. I never experienced any popping whether using the pedal as stand alone or in a pedal chain.



There is a Balanced Direct Out ¼” TRS (stereo) jack socket allows connection of the LA-1A to mixing desk, computer soundcard or external audio capture device. It is fully balanced and transformer isolated. This Direct Out” option completely bypasses the Gain knob and Boost functionality of the pedal.


There is also an External Select ¼” TRS (stereo) jack socket that enables an external footswitch to be utilized for remote bypass switching and activating the tube boost.

The Effectrode LA-1A comes with a 12V center positive Wall-wart Power Supply. It does have hefty power requirements. Effectrode says a minimum of 1000ma (1 amp). The power requirements and the physical size of the pedal make it not the most pedalboard friendly. That didn't stop me from trying tough and I did get it on my Pedaltrain Nano+ (would work fine on Nano too) and managed to use my CIOKS DC7 to power it. Of course I had to use a CIOKS parallel cable that combines the available milliamps from two ports and also the red center positive adapter. I used two ports, switched them both to 12 volts and was able to provide 1000ma via the parallel cable. That worked and I used the Effectrode flawlessly with the CIOKS DC7.

Here's a picture showing perspective of size.



There is no LED indicating gain reduction.

There are two gain stages. First is a grounded cathode tube stage. The output stage is a cathode follower circuit which also acts as a buffer. While the Effectrode PC-2A uses one tube for all of this, the LA-1A has three tubes. Don't expect the result to be a sound like a tube amp breaking up but there is enough harmonic content to give the pedal character.


Yes, the pedal gets pretty warm.



So how does it sound? Very, very good. I'm already a fan of the smaller Effectrode PC-2A and I thought the PC-2A was a quiet compressor. It is. But plug them both in side-by-side and you will discover that the LA-1A is actually more quiet. So quiet that in many settings you won't hear a hint of hum, hiss, or white noise whatsoever.


The LA-1A is smooth, and just flat out makes everything sound better.

There is no loss of highs or lows. Plenty of headroom even with high output basses. With low peak reduction, the lows seem to be less compressed than mids and higher frequencies which makes playing a 5 string through the LA-1A sound huge. Really, really good. Compared to the Markbass Compressore (another single tube compressor), the highs are less attenuated on the LA-1A which I personally appreciate. The LA-1A isn't quite as dark sounding as the Compressore. That may be a good thing or bad thing depending on your taste. While the LA-1A isn't exactly completely uncolored, it is quite transparent overall. But there is just enough tubey goodness going on to give it some character. It reminds me a lot of the Retrospec Squeezebox in how it sounds and responds. Worth noting that though the LA-1A isn't exactly small, it is handily more compact than the Squeezbox.

I spent a lot of time A/B testing the PC-2A, LA-1A, Markbass Compressore, and Lightning Boy OP-2.


The Effectrode LA-1A has a unique character. While it is quite transparent, it is adding a presence that many compressors simply can't.

I'm a big fan of the Markbass Compressore but when comparing side-by-side, the LA-1A simply sounds better to me. It offers a wider feel and better low end response. More of the "studio feel" people talk about. I also like how open the top end feels with the LA-1A (even without the EQ switch enabled). The whole thing is has an inherent sweetness, while at the same time being punchy and full. Sounds great finger style or slap. The Markbass does offer more control however.

If you read my review of the Effectrode PC-2A you might be wondering about the absence of the Limit/Compress switch on the LA-1A. That's a good question. I found that switch to be quite useful actually. I suppose you could dial in more hard knee (more clockwise on the Knee dial) and increase the Peak Reduction dial for a similar effect. I'd honestly prefer having the Limit/Compress switch on the LA-1A. Yet while the PC-2A has that external Limit/Compress switch it lacks external Attack and Knee dials and for me anyway, having the external Attack and Knee dials is more important.



Compared to the Lightning Boy OP-2, the LA-1A is more neutral, less colored, and more open on the top and bottom. The Lightning Boy is perhaps the more "vintage" voiced compressor of the group. It has the most inherent harmonic breakup quality. The Lightning Boy has an overall darker quality.

Is it worth upgrading from the PC-2A or choosing the more expensive LA-1A? That's a tough one. The PC-2A sounds very good and is one of my personal favorites. It's a great unit, taking up less real estate. To some degree the choice is like spitting hairs. The PC-2A is smaller and less expensive. Both the PC-2A and LA-1A are super easy to use. The external Attack and Knee dials are highly useful and have significant impact on overall ability to dial in the perfect feel. Both sound very similar — until you get them side-by-side. Power requirements aren't has hefty though still requires 12 volts and center positive tip. I doubt anybody would tell a difference when using either in a live situation. To a board or recording device, my vote goes to the LA-1A because it just has this brilliant spacial and full presence that does remind me a lot of the Retrospec Squeezebox. The Retrospec is probably more versatile overall (having an actual XLR connection, EQ dial, etc.) but it is a lot bigger and even more expensive.


The PC-2A is probably most similar to the Retrospec Squeezebox in terms of its "bigness" and smoothing effect.



The quality of the LA-1A is superb in every regard. It is an expensive compressor, but oozes quality and majorly wins in the tone zone. Is it worth the price and giving up the real estate on a pedalboard? I can't make that decision for you. As for me, I really like it. It is one of my favorites.

Retail price: $469




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