For decades, the Universal Audio/Urei 1176 has been a favorite compressor for many tracking and mixing engineers because of its ability to add attitude and vibe to any source. They smooth out the peak transients, bring the source to the front of the song and make it sit just right in the overall mix.

There have been many revisions to the 1176 over the years, some have been minor adjustments, while others have been a complete makeover to update it to the current standards of the music industry.

The first 1176 was designed and released in 1967 by Universal Audio founder Bill Putnam. The Rev A was originally developed to be used in broadcast applications so the level was consistent no matter where the listener was tuning in. It featured a Class A design preamp using FET in the voltage divider configuration for gain reduction, which was a technological first.

Shortly after its release, audio engineers began using the 1176 in the recording studio to control the dynamics of vocalists, and the rest is history. The Rev A is one of the most sought-after versions of the 1176, which features a brushed aluminum faceplate and the infamous “Blue Stripe.”

World class mix engineers still use them to this day on countless hit records including Chris Lord Alge and Michael Brauer. The circuit has been modeled countless times by plug-in companies, including Waves for the Chris Lord Alge classic compressor series, Slate Digital, Universal Audio’s UAD-2 platform and many more.

We thought it would be fun to do a shootout between two distinct variations of the 1176 compressor, the Rev D and the Rev F. So I grabbed some source material from a session I did a while back and put them to the test on bass guitar, electric guitar and vocals.

Watch our 1176 Rev D versus Rev F shootout below and continue on to learn more about the shootout and what makes these versions of the 1176 unique. 

The History Behind The Rev D And Rev F
The Rev D was the first revision to redesign the circuit board to accommodate the LN circuit directly on the main board rather than through a module. 

At the 45 Factory, I to get to use a vintage Rev D on a variety of projects. It has a magical quality that really can’t be matched by a plug-in. Just running something through it without any gain reduction happening adds a glow that beefs up any source.

We also have a vintage Rev F, which is the 1176 that I’ve been the most familiar with over the last six years as a tracking and mixing engineer. The Rev F is one of the most commonly used 1176 revisions in the industry, where the older versions had around 1000 units or less available, the Rev F has around 5,000 or so on the market.

It was the first 1176 to change the output amplifier to Class A/B rather than pure Class-A. The output transformer was changed to the B11148 type with 12dB of gain, which is the same transformer as the LA-3A. The push-pull design provided more output drive and was based on the 1109 preamp.

Alright, let's get to the particulars of the shootout.

Bass Guitar
The first source I put to the test was bass guitar. I’m a huge fan of what an 1176 does to an electric bass. It smooths out the initial transient response but doesn’t crush it, adds sustain to the tail of the notes and increases the overall harmonic content of the signal. If a bass guitar is ever getting lost in a mix, try adding an 1176.

I copied the track to two channels in Pro Tools, ran out the Burl convertor into each compressor then returned the processed signal back to the line input of our Tree Audio Roots console. This way I could press the mute buttons on each channel simultaneously and A/B the two compressors.

I dialed them in to be hitting the same amount of gain reduction and overall output on the 1176 meters and also made sure that the output of each track was hitting the consoles mix bus meters at the exact same level. Each unit has slightly different settings due to the difference in circuitry, but I wanted to do a sonic comparison rather than matching the settings.

The bass track was recorded by Takashi Iio on his American Fender P Bass for the song “Someone’s Not Coming Home Tonight” by Kramer Holmes. He played his bass through an Acme Audio Wolfbox DI, which then went into a vintage Neve 1073 preamp. There was also a Neumann TLM103 on his Aguilar Tone Hammer to capture the vibe of the amp. I then did a volume blend of those two channels and committed them to a single track in Pro Tools.

When I was bouncing back between the two compressors, it was hard to say which one I thought sounded “better.” They both were doing things that I really liked and thought would improve the sound of the bass in the mix, but they were totally different.

The Rev D had a much fuller bottom end and smoother quality to it. I wasn’t really hearing the compression even when it was hitting around -6 dB on the louder transients, but I could hear what the compressor was doing to the vibe of the signal and how it was smoothing out the overall performance.

It was also adding a nice punch to the mid-range that would help the bass cut through the track a little bit more. Although I could hear a sonic difference in the higher frequencies of the bass (which there really wasn’t too much happening above 2kHz to begin with, as I going for that classic Motown Jamerson feel) it wasn’t “opening up” the higher frequencies, it was just adding some glow up there.

The Rev F was quite a bit different. Right off the bat, I noticed there wasn’t as much boost in the lower frequencies. The Rev F seemed to lack a bit of the “meat” that the Rev D added. I could also hear the compression more, although they were hitting the exact same on each meter, the Ref D seemed to be a little more transparent.

There was however much more excitement happening in the higher frequencies. I think the Rev D would be the ideal choice for this particular song, but I think the Rev F would be better to make the bass guitar cut through a mix that had more distorted guitars and heavy vocals.

Electric Guitar
The 1176 on an electric guitar does such magical things, the most important of which being increasing the overall harmonic content of the recorded signal.

This particular performance had a lot of attack on each note. I pulled the electric guitar from the same song as the bass. It was performed by Joey Gaydos Jr on his Gibson Flying V through a vintage Fender Blues Deluxe amp.

I used three microphones on the amp, one was a Shure SM57 another was a Royer-121 with the capsules right next to each other close to the speaker. The Shure SM57 was going into an Avalon 2020 and the Royer was going into a Manley Voxbox. The third mic was a Coles 4038 about six feet away from the amp which was in an isolation booth. I ran that microphone through a Universal Audio 6176. I blended the three tracks together with a volume blend and committed them to a single track in Pro Tools.

The Rev D shined on this example in my opinion. Like I said earlier, there’s just something magical that happens in the lower frequency range. I thought the source material sounded great to begin with, but once I ran it through the Rev D it took on a whole new life.

The attack of his notes was still coming through great, but just a little smoother overall. You could hear the chunkiness and richness of the bottom end so much more, which isn’t boosted in volume, it’s more like a depth control was turned up. Some of the notes were hitting around -8dB to -10dB of compression, but it never sounded really compressed to me.

The Rev F still sounded good in my opinion, but just like the bass example, lacked the low end presence and glow that the Rev D was adding. I could hear much more presence in the mid-range and higher frequencies compared to the Rev D, but in comparison, it felt like it has a “plastic” sound.

The compression was a bit more noticeable as well, I could hear the Rev F holding onto the compression longer than the Rev D even though the gain reduction meters were responding exactly the same.

The Rev F is really good for adding attitude to a heavy, more distorted guitar tone and also a great compressor to use as a parallel guitar bus. Blending the parallel compression from a Rev F 1176 to a group of rock guitars will make them shine right through a mix. On this more old school Motown sounding song, I’d have to say the Rev D took the win.

I like to save the best for last, I’m always the most impressed to see how a compressor reacts to the human quality of a vocal. No circuits or trickery changing the vibe of the source, just pure raw performance.

This vocal also came from the Kramer Holmes track as the other two examples and was performed by Greg C Brown. He is one of the best singers I’ve had the pleasure of working with. We recorded the vocal in the middle of the live room at RMS Studios in Birmingham, Michigan, with a U87 run into an Avalon 2020 preamp, Neve 1073 EQ and compressed slightly with a Manley Vari-Mu. We were going for that really live feel with a slight bit of drive from the preamp, classic Motown sound. The reverb is the natural ambience of the live room at RMS.

For the example, I hit the compressors a bit harder than I would in the actual mix because I really wanted to hear what they were doing. The Rev D hitting harder on the gain reduction was a bit more noticeable in this example than bass and electric guitars. There is a certain point where the Rev D grabs the vocal quite a bit, but you can hear the “meat” being brought out.

Just like the other sources, it added a nice layer of warmth and depth to the low end. The vocal performance is very dynamic and the Rev D did a great job of taming the levels without squashing the performance. Overall, it was a smooth sounding compression. It also brought out a bit more of the warm room tone.

The Rev F was adding some more bite to the vocal. I could hear the compressor working harder due to the higher amount of gain reduction happening. The Rev F didn’t improve the depth of the vocal like the Rev D, I think it kind of thinned it out a little bit.

However, it did add more attitude when Greg hits those emotional notes, which I think would add some soul to the track. It was also bringing out much more of the room tone than the Rev D, which was increasing the length of the decay and the tone of the room.

If I were to be remixing this song, I would use the Rev D directly on the vocal channel, then use the Rev F in parallel to get that excitement in the notes that had more emotion, and try to bring out a little more of that natural room reverb.

I had a blast hearing these compressors back to back on the same sources. They both were doing some great things that I could see being very useful on different genres of music. Both had some great characteristics that would work well in parallel depending on the style of tune you’re working on.

Recreating the 1176
Be sure to also check out some of the replicas of the 1176 that Vintage King has to offer. The Purple Audio MC77 makes a recreation of the Rev E with the ability to link two units, true bypass to A/B pre and post compression and switchable power transformers.

Universal Audio also makes the 1776LN which is a reissue based on the Rev C, D and E (most similar to the E due to it’s switchable power transformer) and is the same configuration found in the 6176 channel strip.

Serpent Audio makes the Splice SA-76, giving you the best of both worlds with the ability of switching between the classic Blackface and Blue Stripe 1176 models. You can also choose to blend between the two compressors to create a whole new sound altogether.

For 500 series users, be sure to check out the Serpent Audio Splice SA76-500, which is a recreation of the Splice SA-76 that packs all the sound and functionality into a single 500 series module.

If you’re interested in picking up an 1176 for yourself, be sure to contact one of our Audio Consultants at Vintage King via email or by phone at 855.614.7315. Our team members can help you find the best revision for the style of music you most commonly work on.