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What tube is shipped in a Tonebone Plexitube?

Although this changes depending on supply, it is usually a Ruby Tube 12AX7. This is the most common tube made and is the same as employed in most guitar amps.

What does the tube do inside the Tonebone Plexitube?

The tube is used to generate harmonics and warm up the signal path. The tube is combined with three gain stages to create the Plexitube's rich distortion.

What happens if I change the tube to another brand?

Changing the tube will only affect the sound a little bit. Try changing it if you like. Some guitarists have changed the tube to find that they preferred their new sound. Others have found they preferred the factory tube sound.

Don't tubes required high voltage to work?

This is true. To make a tube sound good and clean – as when used in a microphone preamp or high fidelity amplifier, you require lots of voltage. Since we are not trying to make the tube sound good, but instead are trying to get the tube to distort, we starve it to suit our purpose. Nasty trick… but it works.

How important is ventilation and cooling for tube life?

Because we are 'starving the tube' with low voltage, the tube will last a long time and will never get very hot. The air vents on the side panel provide sufficient ventilation to keep the Tonebone running cool.

How often should the tube be replaced?

After 2-3 years of normal use, you may change the tube. We suggest only doing so if you find the tone is lacking or the output is down from when you first plugged it in.

How do I change the tube?

Complete instructions with pictures are provided in the Plexitube user guide.

Does the Plexitube come with a power supply?

Yes, a 15-Volt DC 400 mA power adaptor is supplied. Adaptors are available for most countries.

Where can I purchase an extra Tonebone power supply?

These are available at larger on-line stores.

Why does the Plexitube require 15VDC to work?

Even though we are starving the tube, we still need sufficient voltage to get the heater coils to work. The typical 9V supplies just do not have sufficient voltage to do the job.

Are there any manufacturers that make multi-power supply bricks for Tonebone pedals?

Yes; The Cioks DC10 and AC10 both have 15V outlets for Tonebone pedals.

Can I use 16V or 18V outputs to drive the Plexitube?

Yes, but doing so will cause the regulator to heat up and reduce the lifespan. So instead of maybe getting 20 years of life, this could be reduced to 18 or less, depending on the voltage being applied. Make sure that you apply the proper polarity or else you can blow up the front end!

Is the Plexitube a 'true bypass' pedal?

Yes. When the pedal is off, the sound passes straight through, without connecting to any electronic circuitry, even if the power adapter is not plugged in.

What is 'true bypass'?

True Bypass means that when the pedal is off, the signal passes right through. Most pedals are NOT true bypass as true bypass pedals are notoriously bad when it comes to popping when switched in and out of the signal path.

How does the Plexitube avoid popping?

We actually apply a very slight load on the pickup at all times to eliminate the on-off 'spark' that causes the pop when switched. Think of Tonebone pedals as 99.999% true bypass.

Can the Plexitube be plugged through an amp effects loop?

Yes. Most guitar amps are designed to connect pedals using the amp's rear panel effects loop.

Is there any advantage of using the Plexitube in an effect loop?

It depends. As far as sound quality it should not make any difference. On the other hand, if you are using a brand of pedals that does not have true bypass, then it is nice to get these out of the loop when not being used.

Can I record direct, straight from the Plexitube's output?

Yes, but keep in mind that guitar amps employ 12" speakers while studio monitors are equipped with tweeters. You will need to compensate by toning down the top end.

How can I get more sustain with my tone?

Sustain is created by combining distortion and mid range. Engaging the MID BOOST and FAT voicing switches will add tons of sustain!

What amplifiers were used when developing and testing Tonebones?

As most guitarists know, the mother of all amplifiers is the Fender® Bassman. Tonebones were optimized using the vintage tube amps as a starting point and then each was refined based on where we wanted the sound to go. The Marshall JCM800 was our model for the Hot-British (and Plexitube) and we used Fenders and Mesa Boogies as a base line to develop the Classic (and Trimode).

What made you select the EQ points that you did?

After years of working with musicians and then applying facts such as where 12" drivers work and how popular amps such as Marshall and Fender work, we found that these frequencies seemed to fit very well in the scheme of things.

When did you first start making distortion pedals?

The first distortion pedal made was a custom solid-state device in 1975. The first tube distortion was tested around 1978. These were not very good, but they were our roots. We made dozens of prototypes in order to get us to where we are today!

The current Tonebone Plexitube looks different from the original one from years ago. Has the sound changed?

No. The sound is exactly the same. We improved the graphics, moved the LED, and added an extra filtering on the power side. Same 'Bone sound, same 'Bone channel.

Can I use the Plexitube on bass?

Yes. We recommend using the BigShot MIX along with as it lets you blend the original bass tone with the distortion.