Rogue Audio Frequently Asked Questions: (UNDER CONSTRUCTION!)

Are Rogue Audio products manufactured in the United States?
Yes! Every single Rogue Audio product is hand built at our factory here in Brodheadsville, Pennsylvania. And from the software on the programmable chips to the amplifiers circuitry, all of our products are designed in house by our engineering team.

Is it difficult to bias a tube amp?  
Not at all. All of our tube amps have a built in meter and it takes just a moment to set the bias. To see just how easy it is, click on the following link to watch a short video (bias video)

How long do the tubes last?
Preamp tubes and the small tubes in the power amps typically last at least 5000 hours before they need to be replaced. The larger power tubes in the power amplifiers depend somewhat on how hard they are used. "Typical" lifetimes are about 3000 hours which equates to about 3 years if used for a few hours every day.

How do I know when my tubes need to be replaced?
If a tube becomes noisy or sensitive to vibration (microphonic) it should be replaced. If a power tube in an amplifier repeatedly blows its fuse or just stops working (or operates intermittently) it should be replaced.

Are tubes easy to replace?
Yes, the tubes just pull straight out of their sockets. When installing new tubes they are only able to be installed in such a way as to ensure that they have the correct orientation.

Where can I get replacement tubes?
We recommend you get replacement tubes directly from Rogue Audio. We treat this as a service so we have some of the very best tube prices.More importantly, the tubes we sell are spec'd for use in our equipment and thoroughly tested before you put them in your amp or preamp.

Can I use NOS (new old stock) tubes in my amp or preamp?
While we use the very best tubes in current production, many of the older American and European tubes can sound even better. If you want to try "tube rolling" just be sure the tubes come from a reliable source and that they are both quiet and non-microphonic.

What speakers do you recommend?
We recommend you use the speakers that sound best to you! All Rogue Audio equipment is engineered to be very "friendly" with other gear. You are unlikely to find speakers that won't work well with our amplifiers as they are designed to drive even the most difficult loads. As long as the amplifer is capable of driving your speakers to the volume levels you enjoy, it will likely be a fine match.

Will my Brand X power amp work well with a Rogue Audio preamp?
Any well designed power amplifier (tube or solid state) should work fine with a Rogue Audio preamp. We design our preamps to have a very low output impedance so that there are no impedance matching issues to be concerned about. As long as the input impedance of your power amp is at least 10K ohms, you won't have a problem.

Will my Brand X preamp work well with a Rogue Audio power amp?
Yes. Generally speaking tube power amps are much easier to drive than solid state power amps. Tube amps usually have a very high input impedance making the preamplifiers job much easier.

Do you recommend a specific brand of cables?
We recommend you use the cables that sound best to you! All Rogue Audio equipment is engineered to be as cable independent as possible. We have never found cables that make our amps misbehave. That said, cables do make a difference so choose the ones that sound best to you.

Is it worthwhile to upgrade my power cord?
The power cords we supply with our equipment are not the prettiest, but they are of a much better quality than the typical computer power cord. They are shielded (important) and of of a sufficient ampacity to meet the requirements of the specific product they are supplied with. If you decide you want to improve on this, be sure the new cord is shielded and of a very high quality.

How much airspace do I need around the Rogue Audio component?
For preamplifiers as well as our hybrid amplifiers just an inch or two on all sides will be sufficient. You will have no problems placing these pieces in an enclosed cabinet if necessary. Our tube power amplifiers and pure tube integrated amplifiers should be placed in or on a shelf with at least 6 inches of free air space on the sides and top. If this isn't possible please give us a call for further options.

What is "ultralinear" mode on your power amplifiers?
Most tube amps use a transformer between the tube circuitry and the loudspeaker to match their impedances and achieve maximum power transfer between the two. There are several ways to connect the output transformer of a tube amp to the tube circuitry. The three most common methods are triode, ultralinear and tetrode. With triode you achieve the lowest distortion level but also the lowest power. With tetrode (or pentode) you get the highest power output but also the highest distortion. Ultralinear operation, where special taps on the transformer are connected to the circuit, provides nearly the same power output as tetrode but with very low distortion figures like triode.

Will triode mode or ultralinear mode sound better on my loudspeakers?
The relationship between the crossover network and tube circuitry is complex and varies with every speaker type. Some speakers sound better in triode and some sound better in ultralinear. You may even find that the difference is quite subtle and difficult to discern. Best bet is to try both and see which sounds best to you on your speakers.

Many other FAQ type questions are answered in the Mark O'Brien interview in Dagogo. Click on this link to read it!