I’ve said it before; I really like being in audio production right now. There is a seemingly endless supply of small manufacturers that are bringing innovative products to the market. This is certainly true in the area of mic preamps, for example. As digital recording has increasingly become “the way things are done”, people have looked to outboard gear, especially mic preamps, to provide some sonic character and musicality. Therefore, tubes and transformers have had an enormous resurgence. Sonic Farm has introduced a slightly different take on a dual-channel, tube mic preamp in their first product offering. It’s called The Creamer. Why is it different? It’s different for a couple of reason, but let’s start with the big one: it is a design that employs no negative feedback. I know — you were hoping for a bigger punch line, but it really is significant. Negative feedback is a very common way of designing a circuit. It sends a percentage of the output to the inverting input to reduce the distortion specs of the circuit, and to help add some stability. Sonic Farm takes the view however, that in the process, negative feedback also robs the signal of some of the desirable harmonic content that tubes provide. So they have taken on the daunting challenge of building a mic preamp with no feedback, but with acceptable distortion specs. And they seem to have done it. The specs are certainly not in the league of super clean, tweaky audiophile preamps, but that’s not the goal or application. For example, before clipping, the THD is 2%, but it is considerably less as the gain is reduced. But keep in mind that some coloration is the goal of this preamp.
Let’s look at the slightly unconventional feature set. Due to this approach to circuit design, the controls are a bit different. The first thing you notice is a lack of the traditional input-gain control. At first, this might seem limiting, but keep in mind that other preamps, such as the coveted V72, have no input-gain control at all. The maximum gain of the preamp is a whopping 74 dB, and there are a few different ways you can control this. First of all, you have the unusual feature of switching in an additional 6 dB of gain directly from the input transformer if desired. This will drive the input of the tube a bit more. It also has a 20 dB pad that can be switched in to drop the signal down if you’re using a condenser mic with a hot output, for example. Then, there is an additional “gain up” switch that increases the circuit gain (as opposed to the transformer gain switch that I mentioned earlier). If needed, these switches can be used in conjunction with each other.
But wait! There’s more! There are a couple more significant ways to adjust the gain and tone. This preamp has the highly unusual feature of being able to switch the configuration of the EF 86 tube gain-stage from triode to pentode. This has a sonic effect on the signal, as well as a gain increase in pentode mode. I found the character to be slightly thicker in pentode mode, in addition to the increased gain.
The last amazing feature to affect gain and tone is the output circuit. First, let me mention that this preamp uses a discrete, transistor output driver that can be switched between solid state with no transformer, or it can use the Cinemag transformer to be the final output. (One side note, the preamp can be ordered with nickel or steel transformer windings, or even one channel of each.) Also, they have included switchable input impedances. This takes a little explaining, and I’m not sure I’m up to the task. The three-way switch has a 1.2k, 2.4k, and 10k setting. So what’s confusing? Well those values are affected by the +6 gain switch on the transformer, as well as whether or not the tube is in triode or pentode mode. So, there is a formula to figure out the multiples in these modes to know the impedance settings. (I was told there would be no math.) I must admit, I kind of just listened to it instead of pulling out the slide rule to know the actual values in all of these modes. Other features include a high pass filter at either 80 or 160 Hz, a polarity-reverse switch, and a 1/4’’ instrument input, as well as individually switchable 48 V phantom power. There is also a variable output-level pot.
I had a pre-production prototype, serial number 002. It looked as good as any high-end production unit I’ve seen. The build quality was excellent without a hint of a wobbly switch or a flexing chassis. Usually pre-production units have little build details that need to be refined, but I saw no evidence of that at all with the Creamer. It has a classic, vaguely vintage look with a two-tone faceplate and cream colored chicken-head knobs.
I used this preamp on a variety of sources. First, on electric guitar, I set up mics that I’m used to using. I often use a couple of mics on a guitar cabinet so I have some tonal choices later on. In this case, it was a Royer R-121 (Tape Op #19) and tube condenser mic that will be the subject of an upcoming review. The guitarist I was recording has tracked many hours in my studio and is very used to the setup. He immediately commented on the sound, saying he felt it was very natural and detailed. The only change from his normal setup was the Creamer preamp, instead of a tube preamp that he normally tracks through. Although it took me a moment to settle on the correct switch setting for the various gain options, I chose pentode mode with the transformer output pretty quickly. I found that I needed to employ the pad on the condenser mic. Since the pad is a 20 dB pad, I had to really crank up the output level to get to the desired tracking level. I didn’t expect to have to compensate quite that much with the output control. It had gone from almost full counter-clockwise without the pad to almost fully clockwise with the pad. This wasn’t really an issue, as I was able to dial in enough gain. I found that I really didn’t need to use any EQ to get the presence that I needed from the guitar. It just sounded good from the start.
I also used the Creamer for tracking acoustic piano, acoustic guitar, and overheads for drums. In each case, the character was never anything but great. I found it to always have excellent presence and detail, much more so than other tube preamps that I routinely use. Vocals were wonderful through the Creamer as well. There will always be times when I need the lushness of a UA 2-610 (Tape Op #27) on the 500 ohm setting for a vocal, but in general, the Creamer provided an amazing immediacy. I loved having the ability to tailor the character by changing the tube stage from triode to pentode. I felt that there was just a little more tube character on the pentode setting, with triode being slightly cleaner. And the option to switch the transformer in and out allowed the ability to have a little more “beef” to the sound, or have it more transparent.
In these days of hybrid mixing, I don’t think I can do a mic preamp review without using it in a passive summing application. Since many people are mixing using a passive summing device such as a [Roll Music] Folcrom (Tape Op #45), there’s a need for makeup gain options that have different characters. I pulled up a mix that had previously been summed with a Folcrom using a different tube preamp for makeup gain. After level matching,I ran a version of the mix using the Creamer. Due to the many options of impedance, tube configuration, transformer output, and gain setting, I ran many versions of the mix using these options. After painstakingly reviewing the endless array of mixes that I had compiled, I settled on having a slight preference for the pentode setting with the non-transformer output. It seemed to have the right balance of body and clarity for this particular mix. But how did it compare to the mix that I had done with a different tube preamp? It…… um…… blew it away. The most obvious thing it revealed was how non-linear the high end was on my “usual” tube preamp. My preamp sounded smeared in the upper midrange as it transitioned into the high end. In comparison, the Creamer just sounded like it had smoother and better high frequency response. At the risk of repeating myself, it again just sounded amazingly open and detailed. Maybe a touch less “tubey-gooey”, but a much better feeling of transient response. In fact, you could actually see that represented on peak meters. When bouncing mixes through the Folcrom using various preamps, I could see more pronounced peaks on the meters when using the Creamer. This increased transient response gave it a feeling of life and sparkle. It’s my new favorite for passive summing makeup gain.
Do I have any complaints? Not really. The only thing that puzzled me was the switchable impedance. I have several mic preamps that have this feature, and I’m used to how it usually behaves. I must confess that I really couldn’t tell quite as much of a difference with the different settings. The manual does say that there might not be much noticeable difference when using a condenser mic, or when the pad is engaged. That minor puzzlement aside, I was thrilled with this mic preamp. It has caused me to change my “buy list” priorities and figure out how fast I can put one of these in my rack. The other good news is that buying direct from Sonic Farm means it’s an amazing value. This is a high-end, flexible, dual-channel tube mic preamp that can be purchased for $2000. I can’t think of another tube preamp that performs like this for anywhere near that price. Sonic Farm is also developing another version called the Creamer Plus. It will have a bi-level switchable low and high frequency boost, not a dedicated equalizer. But the low boost will be inductor based. It won’t have any additional gain stages, hence the transparency will stay the same. Another addition will be a dedicated line transformer that will enable the preamp to be used in more situations, including mixing. The new model will not be a replacement, but rather a deluxe version that will cost around $2500. The standard version will also continue to be available. I look forward to trying anything these guys come up with in the future. ($2125 CAD direct; www.sonicfarm.com)
–Kirt Shearer, www.kirtshearerproductions.com
Interfaces, Mic Preamps, Recorders | No. 23
Portastudio 788 digital 8-track
by Colin Frangos
The right-honorable Portastudio line has now entered the digital realm, and once again they've produced a well- engineered, affordable product. At the risk of sounding like I'm on the payroll, the 788...