By far the most time consuming and formidable project to date, the Steamroller 300 is here! Six KT88s deliver a whopping 300 watts into 2 or 4 ohms- enough to level buildings, or at least to peel the paint off the walls. This monster was commissioned by another Houstonian, Erik Ingram of the punk band Landfill, always looking for the most extreme bass rig to punish his listeners with.
This amp features custom transformers made to vintage SVT specs built by Heyboer. There is no off-the-shelf chassis capable of containing the Steamroller, so I visited my friends over at American Heliarc and together we constructed the massive 26″ x 10″ aircraft aluminum chassis.
The amp features Gain, Treble, Mid, Bass and Volume controls. Each control features its own voicing switch, except Volume. The three-way gain switch allows for three levels of gain, from a single stage input, to a paralleled input to finally paralleled stages with a cathode bypass cap (read: more, more gain!). The Treble control features a simple bright switch. The three-way mid switch allows for a flat setting, a boosted mid setting and a scooped mid setting. The Bass switch provides a high frequency roll off, which allows access to more dub and reggae style tones.
Whereas my other bass amps have catered to both the Guitarist and Bass player, the Steamroller is truly a Bass player’s amp. All of the voicing switches allow for a versatility unparalleled by any other tube bass amp. Before building this 300 watt I didn’t think I could have ever gotten a good pop and slap tone out of one of my amps but the Steamroller delivers this tone in spades, as well as the classic grind of venerable SVT.
The driver stage is made up of a 12AX7 and a 12AT7 providing smooth, clean drive to the six KT88s. Each KT88 features its own bias control and test jack, allowing you to perfectly match the output tubes for maximum headroom and reliability. With these features if a tube ever goes, you will only need to replace the blown tube, and you will NEVER have to buy “matched” tube sets. A line out feature allows those pesky sound dudes to plug in a DI and send the amp’s signal to front-of-house. The line out signal is tapped straight off the output transformer, so you are getting the whole amp’s tone from this line out. One oversized fan cools the amp, circulating air through the five huge vents on the front and back panels.
This amp is housed in the first stained hardwood cabinet we’ve made, but I don’t think we’ll be offering this feature regularly until I can find an outside woodshop to build them.
Mike Tristan and Tim Wigley helped us record some tracks on the old SSL board at HCC Town & Country. Enjoy!
We will be unveiling the official Steamroller bass amp at the Nashville Guitar Amp show. This amp will have a few more features, but all will be revealed in August as the amp is officially added to our line-up!
In other news, we moved the shop! We now have facilities just outside of Downtown, Houston. The new address is 1505 Gano St, Houston, TX 77009. The shop phone number is 713-229-0629, please call or email before you plan on stopping by.
Space City Rock wrote this great article about the move… Check it out!
