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Focusrite ISA One Classic Single-Channel Mic Pre

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Focusrite // The ISA Preamp Range

Description
Focusrite brings their prestigious ISA preamp legacy to the modern age with the ISA One. This innovative single-channel mic preamp, combining the sought-after tone of the original ISA 110 with optional high-resolution A/D conversion and a versatile DI input.
Legendary ISA 110 Preamp with Lundahl Transformer
At the heart of the ISA One is the same preamp circuit found in the revered ISA 110, using a Lundahl input transformer to impart a signature warmth and character to any microphone. Four impedance settings let you shape your tone, from transparent clarity to a round, full-bodied sound that brings out the essence of a classic mic.
Parallel DI Blends Direct and Preamp Signals
Whether recording vocals or instruments, the ISA One's front-panel DI input provides a separate feed to blend in with the preamp signal. Select high or low impedance and adjust the level to create custom tones not possible with a preamp alone.
Optional 192kHz A/D Conversion for Digital Recording
For those working in a digital recording environment, the ISA One offers an optional 24-bit/192kHz A/D card to convert your analog signals with pristine clarity. Connect the ISA One to your computer via USB or Firewire and capture every nuance of your performance.
Take This Legendary Sound Anywhere
Despite its esteemed heritage, the ISA One is designed for maximum portability with a rugged all-metal enclosure. Use it to warm up digital mixes in your studio one day and enhance live vocals the next. Wherever your music takes you, the ISA One delivers the sought-after Focusrite sound.
Free bx_console Focusrite Plug-In
Your ISA One purchase also includes the new bx_console Focusrite plug-in, modeled after the ISA 110 and ISA 130 modules from the original Focusrite Studio Console. Faithfully recreating the tone and feel of these iconic preamps, the bx_console Focusrite is an invaluable mixing tool for re-amping tracks or adding analog warmth to digital recordings.



Features
- ISA Series Transformer-based Preamplifier
- Flexible Independent DI Channel
- Switchable Impedance
- Headphone Output with Volume Control
- Dedicated Insert Point
- Optional stereo 192kHz A-D converter
- Lundahl LL1538 Input Transformer
- Focusrite offers a 3-year manufacturer's warranty
WARNING: This product can expose you to chemicals including Lead, which is known to the State of California to cause cancer, and Lead, which is known to cause birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
Specs
- Gain range: 0dB to 60dB in 10dB steps + 20dB of variable gain
- Input Impedance, variable as follows:
- (Switched Impedance setting Equivalent Input Impedance at 1kHz)
- Low: 600 ohms
- ISA110: 1,400 ohms
- Med: 2,400 ohms
- High: 6,800 ohms
- EIN (equivalent input noise): –126dB measured at 60dB of gain with 150 ohm terminating impedance and 22Hz/22kHz band-pass filter
- Noise at main output with gain at unity (0dB): –97dBu measured with a 22Hz/22kHz band-pass filter
- Signal to noise ratio relative to max headroom (9dBu): 106dB
- THD at medium gain (30dB): 0.0009% measured with a 1kHz –20dBu input signal and with a 22Hz/22kHz band-pass filter
- Frequency response at minimum gain (0dB): –0.5dB down at 10Hz and –3dB down at 125kHz
- Frequency response at maximum gain (60dB): –3dB down at 16Hz and –3dB down 118kHz
- CMRR=98dB (Channel 1, 1kHz, maximum gain with +24 dBu input)
- Crosstalk Channel to Channel: with 10dB@1kHz input to chA, chB output: 104dBrA. With 10dB@10kHz input to chA, chB output: 84dBrA
- Gain range: –20dB to +10dB in 10dB steps +20dB of variable gain
- Input Impedance: 10kΩ from 10Hz to 200kHz
- Noise at main output with gain at unity (0dB): -96dBu measured with a 22Hz/22kHz band-pass filter
- Signal to noise ratio relative to max headroom (24dBu)=120dB
- Signal to noise ratio relative to 0dBFS (+22dBu): 118dB
- THD at unity gain (0dB): 0.001% measured with a 0dBu input signal and with a 22Hz/22kHz band-pass filter
- Frequency Response at unity gain (0dB): –0.3dB down at 10Hz and -3dB down at 200kHz
- Gain range: 10dB to 40dB continuously variable
- Input Impedance:
- High: greater than1 mohm
- Low:greater than 300 kohm
- Noise at minimum gain (+10dB): –92dBu measured with a 22Hz/22kHz band-pass filter
- Noise at maximum gain (+40dB): –62dBu measured with a 22Hz/22kHz band-pass filter
- THD at minimum gain (+10dB): 0.001% measured with a 10dBu input signal and with a 22Hz/22kHz band-pass filter
- Frequency Response at 10dB gain with –10dB input: 10Hz-100kHz +/- 0.6dB
- Frequency Response at 40dB gain with –40dB input: –2.5dB down at 10Hz and 0dB at 100kHz
- Roll off: 18dB per octave 3-pole filter
- Fixed Frequency 75Hz measured at the 3dB down point
- Moving coil (MC) meter is factory calibrated to 0VU: +4dBu with 1kHz sinewave
- With the VU Cal button pressed the meter can be adjusted on the rear panel to allow 0VU to equal +10dBu to +26dBu with the centre detent being equal to +22dBu
- Peak LED meters calibrated in the detent position for 0dBFS: +22dBu, calibration is adjustable on the rear panel to allow 0dBFS to equal +10dBu to +26dBu
- Routing for MC and Peak1 meter is after the HPF, pre insert send or switched post insert return. Peak2 is always pre ADC channel 2, which can be fed by external input or Instrument input
- LED levels are as follows when peak calibration is set to center detent on the rear panel (This is when using the internal ADC)
- 0: +22dBu
- 2: +20dBu
- –6: +16dBu
- –12: +10dBu
- –18: +4dBu
- –42: -20dBu
- Mic input: XLR x 1
- Line input: XLR x 1 and TRS x1
- Instrument input TRS Jack: XLR x 1
- External ADC input: TRS Jack x 1
- Return: TRS Jack x 1
- Send: TRS Jack x 1
- Balanced line output: XLR x 1
- DI output: XLR x 1
- DI through: TS Jack x 1
- Cue mix left input: TRS Jack x 1
- Cue mix right input: TRS Jack x 1
- Headphones output: TRS Jack x 1
- 8.6 Ib. (3.9 kg)
- 8.66" x 4.1" x 10" - 11.4", (220mm x 104 mm x 254 - 290 mm)
- ISA Stereo ADC (compatible with ISA 430 MKII and ISA One), ISA Stereo ADC (compatible with ISA 430 MKII and ISA One)
Warranty
In the event of a Manufacturing Defect becoming evident within 12 months from date of purchase Focusrite undertakes that the product will be repaired or replaced free of charge if the product is returned to the authorised dealer from whom it was purchased. In these circumstances, or if you need an out-of-warranty repair to your Focusrite product, please contact your local Focusrite distributor in your country of residence or business : Find your local distributor here and you will be advised of the correct return procedure.
Alternatively contact the Focusrite Reseller from which you purchased the product. If you purchase a Focusrite product outside your country of residence or business you will not be entitled to ask your local Focusrite Distributor to honour this Limited Warranty, although you may request a chargeable repair.
Alternatively, the unit may be returned at your cost to the dealer you purchased the unit from so that they can organise a Warranty repair with their Focusrite Distributor.
This Warranty does not include cost of shipping to and from the authorised dealer from whom it was purchased. In every case it will be necessary to provide the original invoice or store receipt to accompany the defective product to the supplying dealer. This Limited Warranty is offered solely to the first purchaser of the product from an Authorised Focusrite Reseller (defined as a reseller which has purchased the Product directly from Focusrite Audio Engineering Ltd. in the UK or its Authorised Distributors outside the U.K,) and is not transferable.
This Warranty is in addition to your Statutory Rights in the country of purchase.
Please note: A Manufacturing Defect is defined as a defect in the performance of the product which may be expected from a reasonable interpretation of the published description and performance specifications as published by Focusrite Audio Engineering Ltd. This does not include damage caused by post-purchase transportation, storage or careless handling, nor damage caused by misuse.
A significant proportion of products returned under Warranty (which are very few in number compared to numbers sold) are found not to exhibit any fault at all. Please check that the mains voltage is correctly set for your local supply and that your connecting cables are in good order and correctly connected.
If in doubt about the product functions please read the user guide and if necessary contact your dealer for advice before returning the product to the supplying dealer. You can also contact the Focusrite Tech Support team at the Focusrite Answerbase for general advice.
Featured Articles
Reviews
5
12 Reviews
100%
of respondents would recommend this to a friend
- Home Studio4
- Professional Recording3
- Amateur Recording1
- Needs RackMount Hardware1
- Experienced3
- Novice1
- Good Audio4
- Easy To Use3
- Professional Functions3
- Versatile3
- Good Power Output2
Reviewed by 12 customers
100% recommend
submitted2 months ago
byChameleon Sessions
fromOklahoma City
Awesome preamp and so much more. Cannot find a better single channel preamp. The DI feature and the headphone out/monitor is so great all packaged in a cool looking box!
Exceeds expectations!
submitted5 months ago
byJon
fromSaint Paul, MN
I've had several preamps over the years. This is my favorite even though it's pretty simple. No E.Q. or compression, but a clear, rich, detailed tone. I also plugged a bass guitar into the DI channel and it was remarkably warmer and rounder, even after a bass DI pedal.
Pre Amp are a necessity for a Studio and this one is Perfect
Verified Buyer
submitted5 years ago
byJoe Z
fromBorrego Springs, California
Pre-Amp conditions were really needed on a Home Studio that both voice or guitar inputted towards improved signals to mixer and compressor fulfilled a rich initial signal to process with all the effects that are available on the array that is in a small home studio. Alternating on using the Pre-amp for voice or switching over to guitar with two microphones lifted a special deal that while playing gave a great Studio Musician condition for someone like myself that has never played in public. It occupies my imagination and has no revenue to interfere with my dance with time as a widowed man.
Never use a Shure SM7B without this!!!!
submitted8 years ago
byCas
fromWest Palm Beach
I bought a Shure SM7B about 3-4 years ago and was starting to get discouraged because my vocals never seemed to stand out or be CLEAN. But after me driving myself to the verge of insanity with trying to get good CLEAN vocals, I decided enough was enough time to buy a Mic Pre. I was told about a cloud lifter but i didn't want to hold back to have to buy something again later so i decided on the ISA One. Vocals instantly became better and CLEAN. I can't crank the mic pre too much as my room isn't fully treated so it will start too pick up noise in the environment. Also having the ability to choose between Line level or Mic level really helps. Great Mic Pre
Great Pre
submitted10 years ago
byAustin
fromSalt Lake
Awesome Preamp! I've had this for about 2 years now and I've never been disapointed. Also just added the a/d card to optimize performance. Sweet unit.
SIMPLY GREAT
submitted12 years ago
byMark Westphal
fromCentreville, Virginia
What a great pre-amp! I've been dealing with a lot of cheap ones that sound ok, but when I connected this ISA ONE to my Shure SM7b, it was like the clouds rolled away, and all was great. Absolutely no noise, and this holds true for all of my mic locker...condensers, ribbons, etc. I can't recommend this enough, and talk with your Guitar Center pro audio guy, and he will probably give you a nice break on the price. Focusrite...you got it right.
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