It's crazy to think that a piece of equipment with such simple controls could change the face of the recording industry. 60 years on and Pultec designed gear is still being used by many of today’s top recording and mixing engineers, whether it be original, reproduction or of the plug-in variety. 

The History Of Pultec
It all started in 1953 with the EQP-1, which was the first passive program equalizer on the market. This was a game changer in recording studios, as you now had the ability to manipulate the sound even farther than before, bring it closer to the front of the mix and make it feel as if you’re in the room with the performer.

In the early days, each Pultec piece was hand-built to order by Ollie and Gene in their warehouse in Teaneck, New Jersey. To this day, it would be hard to find a piece of gear that is built to the quality of a Pultec, which is why many of them are still in working condition. Many companies have tried to replicate the sound and build quality of the original Pultec design, and while some of them sound really good, there’s nothing quite like the sound of a vintage EQP-1.

In regards to the EQP-1, the term “magical” seems to be appropriate. There’s something about a Pultec EQP-1 that enhances anything you run through it, even if you don’t apply any EQ. There’s a glow that happens within the tubes and transformers that adds some weight in the low end and opens up the top.

The EQP-1 Design
The original design utilized a custom passive circuit of Gene's design. With a passive EQ, you have to apply 16dB of make-up gain when returning the signal for it to be at nominal level. Although most passive EQs sound great, they’re kind of a pain to set-up, and the sound is always altered by what you use for the make-up gain, so you end up spending a lot of extra money on a
high quality clean preamp used just for boosting signal from the EQ.

The EQP-1 utilized the passive circuit, but included a tube gain make-up amp to get around the typical 16dB of gain lost from a passive EQ. This made a stand-alone Pultec “lossless” because what went in came out the same level, but the signal was actually being enhanced by the additional tube circuitry in all the right ways.

Pultec also made a solid state version of the EQP-1 which had a silver face, but it didn’t add all the depth and color of the tubes.These days, you would be more likely to see a Lang solid state EQ than a Pultec, which has a very similar sound and greater availability.

The controls are very simple, you can select three frequency bands with the option to either boost, cut, or both. On the low band, you can select between four fixed frequency bands ranging from 20Hz to 100Hz, and have the ability to either boost or cut that frequency.

This section of the EQ is one of the best tools for adding some low end power to any source. Each band is smooth, one of the best things about a Pultec is the ability to dial in extreme amounts of EQ without it ruining the frequencies around it or damaging the integrity of the original recording. The way the Q works as you boost the selected frequency makes all the other frequencies around it react in a complimenting way.

Although in the manual for the EQP-1 it says you shouldn’t boost and cut the same frequency, over the years engineers have discovered that something special happens when you dial in the boost and cut together just right. This is because the boost has more gain than the attenuation has cut, and the two controls affect slightly different frequencies. It’s hard to describe what it actually does, you just have to hear it for yourself, but you can hear a smooth bump happen where the boost meets the attenuation, which adds a lot of body to the selected frequency without any muddy buildup below. This works wonders for a vocal, kick drum, snare drum, toms, electric guitar, bass guitar and acoustic guitar to give them weight and punch.

The high band has seven selectable frequencies ranging from 3kHz to 16kHz with only the ability to boost. This band also utilizes the Bandwidth control, which will determine the shape of the Q from narrow to broad. When it’s set to narrow, the boost will affect the selected frequency and a very small range above and below. When it’s set to broad, it will work similarly to the low band, adding a wide and smooth boost to a larger range of frequencies above and below the selected band.

Each of these frequencies has a unique color to them and can be useful on just about every instrument. The 3kHz - 5kHz bands with a broad bandwidth are great for bringing something close to the front of the mix. It adds some presence to guitars and vocals without making them harsh, and has a nice way of bringing out the ambiance of a room microphone.

The 8kHz - 16kHz bands are used to open up the top end of anything you run through it. The 8kHz and 10kHz bands will add a little bit of bite and make something poke through the mix, where the 12kHz and 16kHz bands are silky smooth and used to bring out the air of the source.

The high band is where most of the magic happens in the Pultec. Never be afraid to try extreme amounts of EQ, as most of the time any color that it ends up adding will be pleasing. If it’s not, the controls are so simple you can easily dial in a great sound.

Unlike the low band, the high frequency attenuation isn’t determined by the selected frequency, rather the small dial on the top right of the EQ, with the options of 5kHz, 10kHz, and 20Khz. When applying extreme amounts of boost, it's always good to work with the attenuation as well. When you get it dialed in just right, the boost will be smooth around the selected band and enhance a small group around it.

Once you dial in a sound that you’re looking for, switch between the other bands available to see how the Pultec reacts. Keep the boost, cut and bandwidth settings the same, and just change the frequency selector dial so you can get back to the original sound if none of the other bands end up sounding better.

Variations on the EQP-1A and New Innovations
The EQP-1 has had a couple different variations over the years. The EQP-1A had modified low-frequency boost and attenuation response curves, two additional peak boost frequencies as well as two high frequency shelf boost curves (the S in the name stands for Shelf). These were extremely rare and had a very limited supply, but in 2014, Pulse Techniques brought it back into production. The EQP-1A has been a favorite to many engineers on their mix bus, it can apply a nice smiley face EQ curve across the entire mix and add that Pultec tube glow. Chris Lord Alge has been using a pair of these on his mix bus for quite some time, I’m sure you’ve heard the sweet sound of this EQ at some point in your life without even knowing it.

In addition to the EQP-1A, Pultec also made the MEQ-5 (TubeSolid-State, Mastering Version), which was an EQ that focused on midrange frequencies. The left band ranges from 200Hz to 1kHz and only has the ability to boost. The middle band ranges from 200Hz up to 7kHz and only has the ability to dip. Since this band overlaps the low and high band, you can manipulate the boost and cut the same as the EQP-1a. The right band ranges from 1.5kHz to 5kHz and can only be boosted. Pairing a MEQ-5 with an EQP-1AS gives you the ability to shape a sound across the entire frequency spectrum. The Pultec Pro plug-in from Universal Audio is based on the pairing of a vintage EQP-1A and MEQ-5.

Pultec has created some other incredible pieces of gear over the years, including a handful of EQ designs such as the EQP-1A3 and EQH-2, high and low pass filters, small mixers and preamps. Recently, Pultec began making their way into the 500 series market with 500 Series modules like EQP-500A and EQP-500S.

As long as people are making records, Pultec will always remain a key element in the recording and mixing process. Their sound has been a part of each and every one of our lives whether we know it or not through the great records of the past. We will always be craving that sound, and if it’s not broken, don’t fix it, Ollie and Gene nailed it on the head with the EQP-1.

If you’re interested in learning more about gear from Pultec, be sure to contact your Audio Consultant at Vintage King via email or by phone at 888.472.9023.