harp tone+



The Harp Tone+ is designed to make any amp a good harp amp by addressing the shortcomings of the guitar amplifier itself: the coupling caps, the excessive preamp gain, and speakers that do not have a good bass response. The pedal is essentially an active 2-band equalizer with a range of 20dB in gain to a reduction of 20dB in level for both bass and treble frequencies. The BASS control works far better than the BASS control on amps because it is tuned to include mid bass and lower mid-range frequencies; this is where the majority of a harmonica's lower frequencies reside. You can increase or decrease your BASS and TREBLE frequencies as well as lower your VOLUME to control feedback or increase your VOLUME if you want a little gain for solos. The Harp Tone+ does not eliminate feedback, but it does help control it. And it has a true bypass.

Why 20dB in gain? The 20dB in gain for bass frequencies is necessary because they are so low in comparison to the mids and the highs that are produced in harps. They are there, but they are at a very low level. This pedal is ideal for increasing bass frequencies in your tone. It is also ideal for amps with no tone control, for increasing volume during solos, for decreasing feedback, and for giving the harp player more control over his tone when playing through a PA.

The Harp Tone+ makes any guitar amp a good harp amp. How? By providing the gain necessary to drive bass frequencies through the low-value coupling capacitors. If feedback is a problem and the amp starts to feedback too early due to the excessive preamp gain found in all guitar amps then by lowering the VOLUME on the Tone+, you can counter that excessive gain, and now turn the amp's volume up to a much higher level where the VOLUME control setting will not be as critical in relation to feedback. Plus, if you have a speaker that is poor on bass response you will now be able to push it harder with higher-level bass frequencies and bring it to life.

How does the Harp Tone+ make any mic a better mic? This ability is possible by the ultra high input impedance, the gain available in the bass frequency range, and the VOLUME control that helps control feedback or add volume, whichever your needs are.

Set the volume on your amp to around 8 and then turn back (CCW) the VOLUME control on the Tone+ until feedback stops. Then set the BASS and TREBLE to your preference and fine tune your volume with the volume control on your amp. This method will help control feedback and allow you to manage feedback easier.

The pedal can be powered with a 9V battery or a DC adapter. The DC adapter requirements are a regulated 9V DC with a minimum 100mA output and a 2.1mm x 5.5mm connector with a negative center. The battery is switched OFF when an external power adapter is used, and the "IN" jack acts as the pedal ON/OFF switch. Lone Wolf offers power adapters for US and EURO customers and is sold separately.

  1. BASS control
  2. TREBLE control
  3. VOLUME control
  4. 9V DC input (barrel with a negative center)
  5. True bypass with LED indicator
  6. High impedance input
  7. Reverse polarity protection
  8. 10-year warranty on parts and labor
  9. If not satisfied, return within 60 days for a refund of the
    purchase price minus shipping and 4% credit card transaction fee

Brad Capper: gives a demonstration of the Harp Tone+.

Andy Santanna: gives us a demo with a Blues Jr. Andy explains why and how he uses the pedal
to produce a fat balanced tone and makes the BJ sound like a boutique amp.

Brian Brazil: Demonstrating the Harp Tone+


The following sample was produced by Stephen Schneider for our forum members, and he graciously offered it for use here: Sample.




Fender Blues Junior and the Harp Tone+:
"Bottom line is that you can get a good harp tone from a Blues Jr with the Harp Tone+. First thing harp players need to do is change out the preamp tubes with V1-V3 as 12AY7, 12AX7, and a 12AX7 phase inverter, using quality tubes. I tried the BJ/HT+ combo with the mic I usually play out with, a 'Harmonica Honker' and a Shure 57 Beta. In both cases the sound was good to very good but I would have liked a stronger presence in what I think is the 3 to 4 Khz range. Here are the suggested settings for BJ/HT+ combo: BJ Master @#10 (not 10 o’clock), Middle 2-5, Bass7-10, Treble 10-12, Volume 5-8. The HT+ settings are o’clock. Bass 2-3 o’clock, Treble 4-5 o’clock, Volume noon to 3 o’clock. This produced good to very good tone. As a dynamic mic player, I want a wider palette so I don’t want the Bass to cut the treble per se, I am happier when they are more independent."

Peavey Transtube Series SS Amp and the Harp Tone+:
"You get very good to awesome results, especially if loaded with smooth, non-ribbed, early breakup speakers. Then the amp just screams (WOW!). You can get that oft wished for 'monster tone'. I love it."

Tom S writes:
"Randy, I just wanted to let you know that this is the BEST of all the devices I've purchased from your store. OMG...I have 2 amps that I never drag out anymore that sound great with the Harp Tone+. Best money I've ever spent on harp gear."
-Thanks again, Tom

An email correspondence:
"Hi Randy, Ed here, I have a couple of your pedals and am enjoying their use weekly. I have rediscovered the tonal possibilities playing thru my Alamo Challenger with the Harp Attack. I also have a Fender Deluxe Reverb that I've had a hard time keeping the buzz out of, is it possible to mod either of these for harp use and what would something like that cost?"
-Thanks, Ed

"Hi Ed, the Alamo would benefit greatly from a tube swap and replacing the coupling caps with .1uf caps, same with the Fender although it is not as simple with this amp which has more circuitry. You could also achieve the same result by using a Harp Tone+ with both amps. I do not know what the cost would be for a mod, you would have to find an amp tech for an estimate."
-Best regards, Randy

Ed decided to add the Harp Tone+ to his chain and here is the result:

"Randy, you have created a miracle. My vintage Alamo amp is reborn into a serious harp amp. The Harp Tone+ with the Harp Attack is a ticket to the Promised Land for me. Signature, robust harmonica tone leaving headroom for extra volume as needed. Oh I forgot to mention feedback control! Did I mention feedback control? With the volume on 8? Say What? I don't know how it gets better than this!"
-Many thanks, Ed


info sheet     power plug drawing

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The Harp Octave is PATENT-PENDING