SA-2A+ – Tube Opto Compressor

Tube-Driven Electro-Optical Compression & Limiting

Next Batch:March 2025

(2 customer reviews)

Original price was: $1,490.00.Current price is: $1,290.00.

Tube Opto Compressor. Identical UREI LA-2A replica.


Three historic LA-2A’s revision in one.

The SA-2A+ is the most authentic and accurate sounding replica of the 1960’s UREI LA-2A on the market today. The LA-2A has been for 60 years one of the most sought-after vocal compressor and for good reasons. With its stunning transformers, circuit and tubes most things sound better by just running through it. The T4B, a unique photocell based Opto element with peculiar time constants evens out any signal with smooth compression and a slow release that makes different to anything else.

At Stam Audio we have been building LA-2A’s replicas for almost a decade and decided and have gone all in on our final revision with customer US made transformers, a new and improved Kenetek Pro Audio T4B cell built in a beautiful 3U faceplate with rack ears and the elusive UK-made original VU meter as well but we didn’t stop there.

We wanted to honor the first 100 LA-2A’s made in the early 60’s (Vintage), the most commonly found UREI LA-2A from the early 70’s  (Standard) and the re-issue from the late 90’s (Modern) each with their own frequency response and THD and behaviour.

Without cutting any corners and making sure that it sounds exactly like an old LA-2A we are confident that the SA-2A+ will be the last LA-2A compressor you’ll ever need.

The T4B

The T4B optical cell is the single most important part of the circuit and heart of any LA-A. Its light dependent function and peculiar time constants are what make an LA compress and sound the way it does. We have tested every T4B out in the market and always end up going back to Bill Jone’s Kenetek T4B made in the USA. Bill Jones has been building T4B’s for over a decade and thanks to his painstaking methodology, dedication and craft he is the only person in the world that can faithfully reproduce the attack and release times of an old UREI T4B. Without this part it is impossible to obtain the original sound.

Each T4B is handmade in the US, checked to be in specs and shipped to our lab in Chile with a virtual zero rejection rate and has lasted years without ever failing.

The Iron

We outsourced these transformers to several manufacturers and ended up settling with two US manufacturers that painstakingly recreated the timbre of the original UTC HA-100X, A10 and A-24 transformers. Thanks to their meticulous craftsmanship we can confidently say the SA-2A+ recreates every drop of character of the original UREI LA-2A both in the top and low end and can be used indistinguishably with an original unit.

The Tubes

Tubes played a big role in the original character of an LA-2A. For the past decade and as long as they are available, we will continue to use a NOS 12AX7 and NOS 12BH7 on the audio path and one JJ 12AX7 tube and NOS 6AQ5 on the control circuit, these tubes simply surpass the audio quality of modern tubes. These tubes are present on both the audio path and side chain of the unit.

The board and components.

Each SA-2A+ features a Vishay Sprague output capacitor, Ohmite carbon resistors on the audio path, precision metal film resistors on the side chain and a state of the art power supply with Vishay capacitors all ensure that the unit runs as quietly as possible and is reliable for decades to come.

Circuit and controls

The SA-2A+ is an exact replica of the original schematic from the late sixties with an emphasis control that allows you to control the frequencies that get compressed, a peak reduction knob to push gain reductio as far as you like, a gain knob and a limit/compress switch that changes the ratio on the unit. On top of this we have added 3 modes to select your favorite character making the most versatile and accurate LA-2A replica on the market.

Aesthetics

Finally, but not least important is the looks. We went the extra mile to source the original LA-2 VU meter, knobs and screws in a beautiful raw brushed aluminum finish including the rack ears famously known as the “silver face”.

Manufacturing

We have made no compromise in parts which ensures you get the best sounding LA-2A money can buy. Every unit is handmade and calibrated in our workshop in Chile where they get a full health check and are burned for 72 hours to ensure your SA-2A will last for decades to come. Stunning vocals. Amazing on bass. In fact, most things will sound better by just running them through the SA-2A circuitry without even compressing.

Stam Audio Engineering products are about sound quality first and foremost. Every component of every unit is premium quality and carefully selected to ensure our units match or even surpass the quality of high-end boutique gear.

100% satisfaction guarantee – if you don’t love your SA-2A+, we’ll refund you

If you’ve used an original LA-2A before, we’re extremely confident the SA-2A+ will put a big smile on your face every time you use it.

However, if you’ve never touched the original before, as gear lovers ourselves we understand that the only way to really know if this compressor is right for you, is to put it through its paces. That’s why the SA-2A+ comes with a 30-day money back guarantee. This allows you to get it into your rack and see how it impacts your recordings. If you love it (and we think you will!), great…keep the unit and create amazing music with it. If not, no problems.

Just send it back to us and we’ll fully refund your purchase.

Technical Specs

  • Original 1962 LA-2A Schematic
  • Vintage, Standard and Modern switch
  • US Made Kenetek T4B Opto Cell
  • US Made UTC HA-100X, A10 and A-24 replicas
  • 12AX7, 12BH7, 6AQ5 Tubes
  • NOS Tubes (per request)
  • Carbon Resistors on audio path
  • Vishay Capacitors
  • Original Teletronix Large VU Meter
  • 3U Faceplate
  • 115 and 230 Switchable voltage
  • Hand Made in Chile
  • 2 Year Warranty

2 reviews for SA-2A+ – Tube Opto Compressor

  1. Sean

    SA-2A

    The original SA-2A was my first Stam Audio purchase, I was looking to add some outboard to my recording chain in order to improve the signal going into the DAW whilst tracking, rather than using plug-ins after the A/D conversion.

    Being based in the UK, I was nervous ordering having only read a few reviews and comments on web forums, But I spoke with Joshua on the phone and was lucky enough to be able to order a rare ‘in-stock’ unit.

    It arrived promptly, and incredibly well packaged. I did have to pay UK customs charges on it which was a drag, but even so it was still a bargain, the build quality is exceptional.

    Without doubt no other single piece of equipment has had such a noticeable effect on my recordings. It was a night and day difference. I honestly couldn’t believe the improvement. Vocal tracks now sounded much smoother and thicker, bass tracks just locked in place and sounded richer and warmer. In fact I haven’t found a single instrument that doesn’t benefit from being run through the unit.

    And it is just so damn enjoyable to use.

    My only problem now is that I liked it so much that I also ordered the SA-76-Rev-A, so now I have to decide which one to use as they both sound exceptional, of course when appropriate my favourite setting is to use them both in sequence!

    I can only imagine that the SA-2A+ is going to please anyone who orders it. Having the extra options will be a great benefit, although I like the limitations of having just the two controls (plus the toggle) on the original model.

    If you are considering a purchase, I say just do it. may take a while to arrive but once you start using it you will be smiling every time.

  2. James Wilkes (verified owner)

    I heard such good things about the first Stam SA-2A that when I heard they were making the SA-2A + I jumped at the chance to get one ordered. Like other Stam products the build quality is exceptional – we went for the NOS tube option. Functionally the dials are really nice and smooth. Sounds fantastic whatever you do with it really ! Wish I had more than one in the rack. Adds a lot of depth and weight to the source as you would expect. A lot of care goes in to making these products which does mean they take a bit longer to manufacture – but don’t be put off by that! Throughout the process I was kept informed with the progress of the build and an expected delivery date. The item was well packaged and we was given tracking information to monitor the delivery. This was our second Stam purchase – hopefully we will be making a third very soon!

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