Download the Valvulator 1 Owners Manual (PDF)

Tonal degradation and signal level loss is generally caused by:
1) Loss of high frequency response due to guitar cable capacitance.
2) Loss of signal level and high frequency response due to the difference between the guitar output impedance and the effects input impedance.
3) Signal degradation caused by noise, distortion, and poor frequency response due to the design of the audio circuitry in the effects device.
See diagram below or download the pdf file.



The VALVULATOR I utilizes a Unity Gain (See FAQ #4) Vacuum Tube based Buffer circuit to change your guitar signal from high impedance to low impedance. This signal is better able to survive the trip from your instrument to your amplifier because the low impedance nature of the signal is virtually unaffected by the above conditions. In addition, the VALVULATOR I input stage utilizes the same circuitry as that found in the input stage of most guitar amplifiers, which protects the guitar signal from alteration. That means this circuit has much more headroom than most stompboxes, so you get the same dynamic feel from your instrument as you would if you were plugged directly into your amp.

Now that you have solved the signal loss dilemma, how do you keep your stompboxes operating at peak performance so your sound will always be there when you want it? The answer is to regulate the DC power going to the stompbox to insure that it will always be exactly the same voltage, no matter where you are. The Valvulator I provides four regulated and isolated outputs which will supply you with all of the clean regulated power you need to insure maximum signal output and frequency response from you pedal devices. And because the power supply outputs are individually isolated, you never have to worry about ground loop hum.

2) Where do I connect the Valvulator 1 in my signal chain?
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The Valvulator 1 is inserted between your guitar and your first effect. Just plug the cord from your guitar into the Input of the V1 and plug Output A into the first effect in your effects chain. That’s all there is to it.
See diagram below question #3 or download the pdf file.

3) What is the second output (Output B) used for?
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Output B is simply a copy of Output A (parallel output) and can be used several ways. If you have a tuner on your pedalboard, you can plug Output B into the tuners input. This will prevent you from having to send your guitar signal through the tuners electronics, which will reduce noise and improve your sound. If you have two amplifiers you can use the V1 as a “Y” splitter, sending Output A to one amp and Output B to the other. Because of the Low Impedance of the V1 output, you can easily drive two amplifiers from your guitar with no loss of gain or high frequency response. Also, you can set up your signal chain so that some effects go to Amplifier A and different ones to Amplifier B. Or you can connect Output A to your amp and Output B to a recording console or direct box for recording and live performance mixing. These are just a few possibilities.
See diagrams below or download the pdf file.



Download the pdf file

4) What is Unity Gain?
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Unity Gain simply means that the signal level at the output of the V1 is equal to the signal level at the input. The V1 does not boost the signal or change the tonal character. This is important because you do not want to color the original guitar sound or artificially overload your effects devices, which may cause harsh distortion or unnatural sounding compression.

5) Why do I get a gain increase when using the Valvulator 1?
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The Valvulator 1 does not increase your signal output or boost the high frequencies. What you are actually hearing is the restored signal level and frequency response that you were previously losing through your guitar cable, effects, the patch cables between your effects, and the cable from your pedalboard to your amplifier.

6) Are some effects worse offenders than others?
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Yes. Signal level losses and high frequency losses are especially noticeable with Wah pedals and Volume pedals. Some modern effects have built in buffers, which help with frequency response, but usually cause a loss of dynamics. This is what contributes to the “flat” sound of some effects.

7) My effects have “True Bypass” so why do I need the Valvulator 1?
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True bypass may be fine when you are not using your effect. But as soon as you activate the effect, you are subjecting your guitar signal to alterations caused by the effects circuitry. In addition, true bypass often causes as many problems as it solves. For instance, you may experience a noticeable difference in signal level when switching the effect on and off. Often a loud pop or snap can occur with true bypass switching. This can sometimes be loud enough to blow a speaker. Radio frequency interference (RFI) can often occur with true bypass pedals. If you have ever heard Hank Williams (For some reason it always seems to be a country station…) or a near-by truckers conversation come blasting out of your amp during a solo, you know how embarrassing this can be during a performance. The low impedance and careful circuit design of the Valvulator 1 will help prevent RFI even in the most radio-sensitive environments.

8) What happens if I overload the input of the Valvulator 1?
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Generally you will not notice overload distortion because your guitar signal is not powerful enough to cause serious overload. However, even if you do overdrive the V1 input, you will be overdriving a tube input stage, which will actually make your tone fatter and punchier sounding. Typical levels of signal overload will not cause damage to the audio circuitry in the V1.

9) Can I use the Valvulator 1 in the Effects Loop of my amplifier?
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Typically this would not be necessary because a well designed effects loop operates on the same principle as the V1. However, all effects loops are not created equal and in some cases the tone of your amplifier may be improved dramatically with a V1 inserted in the amplifiers effects loop.

10) Can the Valvulator 1 improve the sound of digital and modeling devices?
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The answer to this question is a resounding Yes. But to understand why, you need to understand a little bit about how digital devices work. Digital effects and modelers take an analog audio signal (your guitar signal for example) and convert it to digital information before the actual processing or effecting takes place. Once your signal has been converted to digital information, not much can be done. However, all digital effects and modelers have solid-state analog input stages and most of these have fair to mediocre frequency response and very low headroom. Headroom (the maximum amount of signal level an audio circuit can handle before overload) is directly related to the operating voltage of the entire unit. Since most digital and modeling effects operate at very low voltage (typically between 6 to 12 volts), it is very easy to overload the analog input stage causing a flat artificial tone. This is where the Valvulator 1 comes in. Because of the high operating voltage of the tube input stage of the V1, the headroom is also very high. So plugging into the V1 first produces a dynamic, rich sounding audio signal, which is then routed to the digital effect. Your guitar signal, along with the sparkle, tone and punch of the V1 tube stage is now “engraved in stone” and ready for processing by the digital converter. Try it for yourself! And while you’re at it, pay particular attention to the difference in responsiveness of the volume control of your guitar, with and without the V1.

11) Will the Valvulator 1 work with other instruments?
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The V1 can be used to clean up or fatten up Bass (add real tube dynamics to the front end of your solid state bass amp), Keyboards, Microphones, Drum Machines, or any other signal source you can think of. It makes an excellent direct box for recording and pro sound applications and is perfectly suited for home or professional studio applications.

12) How can I power more than 4 effects when there are only 4 power output jacks?
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Each DC output of the V1 can supply up to 80mA of current. The average pedal draws from 10 to 30 mA. Therefore, 2 or more devices can be “daisy-chained” to each DC output as long as the combined current draw does not exceed 80mA. This can be accomplished by your local technician or you can do it yourself if you’re skilled with a soldering iron. Additional cable assemblies are available from an Authorized VHT Dealer or the parts can be obtained from your local electronics store. See diagram below or download the pdf file.

13) How do I power my vintage pedals that do not have an external DC adapter jack?
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Each Valvulator 1 comes with four Barrel to Barrel (2.1mm) type connector cables. Additional cable kits are available direct from VHT or from your Authorized VHT Dealer. Available cable types are:
Barrel (2.1mm) to Mini-Phone (3.5mm), NEGATIVE ground (for american made pedals).
Barrel (2.1mm) to Mini-Phone (3.5mm), POSITIVE ground (for vintage British made pedals and new reproductions of early Brit boxes).
Barrel (2.1mm) to 9Volt Battery Clip. No more drilling holes in your prized pawnshop pieces.

The Valvulator 1 will also operate properly with Voodoo Labs cables, Furman cables and Boss/Ibanez multi-effect adapter cables, which will allow you to run more than one effect per output. WARNING! BE SURE TO OBSERVE MAXIMUM CURRENT DRAW OF ALL PEDALS CONNECTED TO A STRING TO PREVENT BLOWING THE VALVULATOR 1 INTERNAL FUSE!

14) How can I power “positive ground” effects with the Valvulator 1?
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Positive ground or reverse polarity effects can be powered from the DC outputs of the V1 three ways. If the effect has barrel type jack you can cut the plug from one end of the dual barrel cable provided and reconnect it with the leads reversed, or you can connect a new barrel plug to the raw wire ended cable provided. If the effect uses a mini phone jack, you can obtain a reverse polarity mini phone cable available from your Authorized VHT Dealer.

15) How can I connect my 18-volt effects using the DC outputs on the Valvulator 1?
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As long as your device does not exceed 150mA of current draw, you can power your 18-volt device from two DC outputs wired in series. This can be accomplished by your local technician or you can do it yourself if you’re skilled with a soldering iron. Additional cable assemblies are available from an Authorized VHT Dealer or the parts can be obtained from your local electronics store. See diagram below or down load the pdf file.