BLUE Cactus Microphone

I first became familiar with BLUE (Baltic Latvian Universal Electronics) when I reviewed its Kiwi microphone (PAR 7/01) a few years back. Since then I have had the utmost respect for this high-end microphone company.
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I first became familiar with BLUE (Baltic Latvian Universal Electronics) when I reviewed its Kiwi microphone (PAR 7/01) a few years back. Since then I have had the utmost respect for this high-end microphone company. From the introductory $649 Baby Bottle microphone to the top of the line $4,995 Bottle, every BLUE microphone is crafted without compromise to the highest quality standards. The Cactus ($3,295 but streets around $2,800) is no exception, and after spending the past two months using it to record virtually every sound source imaginable, I have come to the conclusion that it's a microphone that will be hard to live without.
Product PointsApplications: Studio

Key Features: Multipattern, ships with power supply, premium mic cable, Anvil flight case

Price: $3,295

Contact: BLUE at 805-370-1599,

At the heart of the Cactus is a multipattern variation of the B7 Bottle microphone capsule. This large diaphragm, single backplate capsule is BLUE's modern-day version of a classic microphone capsule from the 1950s. Rather than building a microphone with an ultraflat frequency response, the Cactus was developed to enhance the projection, air and midrange detail in a voice, while keeping the proximity effect to a minimum.

The Cactus amplifier, which utilizes a hand- selected, subminiature vacuum tube, is Class A and fully discrete. BLUE utilizes electronic components of only the highest quality including expensive metal-film resistors and a handmade. custom transformer. To keep the signal path as pure as possible, there are no pad or low-cut filter switches in the circuit. The amplified signal is taken from the plate and fed through a high-quality polypropylene capacitor, then output through a BLUE custom hand-built transformer. This transformer was designed by BLUE's engineers to match the tube, and to eliminate outside interference (RF, etc.). The transformer is balanced, using a symmetrical two-bobbin design, with a transforming ratio of 10:1. With this ratio, the microphone's impedance is fairly low, typically 150 ohms. The primary transformer windings are connected in series. The transformer's secondary windings are connected in parallel, and connect directly to the XLR output pins. The transformer lamination has a high relative permeability, which is one of the reasons the microphone has a higher dynamic range with very little distortion. The Cactus microphone's internal wiring is Teflon-insulated oxygen-free copper.

The BLUE 9610 power supply for the Cactus features a regulated circuit design. To assure tube longevity and the stability of the tube microphone circuitry, BLUE developed its Soft Start feature. This feature delivers the tube's heater voltage before the plate voltage which lengthens the life of the tube and keeps its noise to a minimum. The Soft Start circuitry also prevents the heater current from exceeding the limits for which the tube was designed. Approximately 80 seconds after the Cactus has been switched on, when the cathode is fully heated, the plate voltage is applied gradually. During this time the output of the microphone is muted. After about three minutes when the tube is settled in its correct operating mode, the mics muting is disabled. Both the heater and the plate voltages are extremely stable and nondependent on AC main changes or fluctuations.

A nine-position switch on the Cactus power supply determines the pickup pattern for the microphone capsule. The pattern is variable from omnidirectional (fully counter-clockwise) to figure 8 (fully clockwise).

The separate power supply has a switchable fuse that sets the operational voltage at either 110 or 240 VAC.

In addition to the Cactus microphone, the Cactus microphone system includes the BLUE Series One shockmount and wire mesh pop filter assembly, a length of BLUE's private stock Champagne tube microphone cable, and the model 9610 power supply. The microphone and all of its accessories come packed in a velvet-lined Anvil-built ATA flight case should sufficiently protect the Cactus for decades to come.

In Use

Recording lead vocals is the Cactus' specialty. I found that the microphone has a slight upper midrange boost that adds a wonderful presence to a vocal without any increase in sibilance. The microphone's bottom end is tight and full and the top end is airy and open. I had equally pleasing results using the microphone to record female and male vocals. I found that the mic's pop filter worked extremely well in eliminating virtually all of the unwanted pops and thumps. While recording vocals, I experimented with a vast assortment of preamplifiers (John Hardy M-1, Geoff Daking, Universal Audio 2-610, Gordon Microphone Preamplifier System) and always had wonderful results. In nearly every instance, the Gordon was the perfect match.

With the capsule set to omnidirectional, I had fantastic results using the Cactus to record a Duncan acoustic guitar. I placed the Cactus facing the guitar neck at approximately the 14th fret (about 2 inches away) and the sound was amazing.

While recording Nashville's Love Sponge Quartet, I had exceptional results using the Cactus to capture John Catchings' cello. This time I used the Focusrite ISA220 Session Pack. Except for a high-pass filter set at 50 Hz the microphone required no EQ and just a hint of compression.

The Cactus did a fine job of capturing the sound of electric guitars. I had my best results recording cleaner tones. I found that distorted guitar sounds have a tendency to be a bit harsh and piercing. One exception I found was setting the Cactus' pattern to omni and placing it about four feet from the front of the guitar cabinet. I combined this signal with a Royer R-122 placed about two inches from the cabinet's grill. The end result was a huge crunch guitar with the perfect amount of room ambience.

The smooth high-end response of the Cactus gave me perfect results when capturing the sound of an alto flute and a penny whistle. The microphone sounded best about 12 - 15 inches from the instrument with a slight amount of compression.

The fast transient response and high-end detail of the Cactus make the microphone an excellent choice for recording drums and percussion. I had good results using the microphone to capture drum kit ambience. The microphone also worked well recording bongos and congas. In both instances the microphone provided a nice attack with plenty of the drums body. The Cactus worked exceptionally well recording tambourine, wind chimes and shakers.

Not only does the Cactus sound good on vocals but it is visually inspiring. Every vocalist I worked with commented on the mic.

BLUE included each of their high- quality microphone cables (the Kiwi, the Blueberry and the Cranberry). I could not tell a difference between the BLUE cables but I was surprised when I compared them to my trusty Mogami cables and found that the BLUE cables sound better. The low-end has slightly more definition and there is more sparkle on the top end.


The BLUE Cactus is a high-quality microphone that works well in virtually any situation. With a list price of over $3,000, your wallet may be the only negative factor in determining whether to buy this microphone.