The ISA series by Focusrite offers some of the highest-quality microphone preamplifiers in the mid-priced range.

The history of this design begins in 1985, when Sir George Martin (known for his work with The Beatles) commissioned the legendary Rupert Neve to create a microphone preamplifier with as little added distortion and noise as possible.

Neve developed the ISA 110 (Input Signal Amplifier) — a preamplifier with a discrete design featuring a transformer-balanced input.

At the heart of this sound lies the Lundahl LL1538 input transformer — a key component in both the original design and the modern ISA models.

We typically describe ISA preamps as clean and transparent — and rightly so. However, when peak levels reach between 0 and 4 VU (+4 to +8 dBu), the input transformer begins to saturate, resulting in harmonic enrichment and soft knee compression. Of course, the effect is not as pronounced as in other Rupert Neve designs — for example, the legendary Neve 1073, known precisely for its characteristic drive.

In the video accompanying this article, we take an in-depth look at the Focusrite ISA One. Despite its name, it actually functions as a dual-channel preamplifier.

You will hear how, during the recording of a female pop/rock vocal with properly set levels, the saturation effect becomes noticeable only when the singer reaches a powerful high belt and the levels move into the “red zone.”

At the other end of the spectrum is the example of a jazz acoustic guitar. Here it becomes clear why this preamplifier has remained a staple in professional studios for four decades. We use a Warm Audio WA-14 (a clone of the AKG 414), positioned 50–60 cm from the instrument. Amplified through the ISA One, the signal remains exceptionally clean, detailed, and natural — a faithful representation of the instrument in an acoustic environment.

In the remaining examples, we examine the DI (Direct Input) section of the Focusrite ISA One. There is a distinctive functionality included only in this version of the modern ISA products, which effectively turns the ISA One into a dual-channel preamplifier. Watch the video to understand how this works, and you will also hear examples with drums, bass guitar, acoustic guitar with DI and microphone, and other interesting demonstrations in which we test the limits of this unique device.

The recording studio is divided into three rooms. The main room is spacious and features very good acoustics. It allows for both precise monitoring with mid-field studio monitors and achieving a very good sound when recording drums in the rear part of the room.
At the other end of the room is the vocal booth, an essential part of every professional studio. Despite its name, it is used for recording guitar amplifiers, acoustic guitar, or anything else that requires a clean sound without reflections.
The entire recording studio, together with the booth, is acoustically treated with panels that absorb the entire audible frequency spectrum. Only the third room uses acoustic foam panels, which is why it has been designated for courses and lessons.

The studio is configured according to the PANGURA Music Studios standard, using an innovative hybrid studio configuration. This is a method that is increasingly used in Western studios. In this setup, recording is done through external preamps and signal processors (compressors, equalizers), which are captured digitally into a DAW (Digital Audio Workstation) via an audio interface — in our case, Pro Tools or FL Studio. This allows us to color and shape the desired sound before the signal is converted to digital, resulting in more natural results compared to processing entirely in a digital environment. The same methodology is applied during music mixing, where the digital signal is converted to analog, passed through analog signal-processing equipment, and then converted back to digital.In the video we have attached, you can see the first week of Pencho Tsochev, founder of Pangura Music Studios, in the new recording studio. It includes excerpts from the studio setup process as well as footage from recording sessions. As early as the fourth day, musicians from the band “Fifth Hour” were in the studio, and we began work on their debut album. The following day, we produced a song for a pop artist. All of this can be seen and heard in the video below.
From Pangura Music Studios, we encourage you to listen with headphones in order to appreciate the unique drum sound we managed to achieve during the very first week of the new recording studio.