Advice about acoustic & harp amps

[Bob S]

Anyone have any pointers about both acoustic & harp amps ?
I have a buddy about to retire who is interested in an acoustic amp and a harp player looking for a different setup for his live playing.
Any suggestions would be appreciated.

[selloutrr]

The Fender Champ and Ampeg Reverb and Jet model's when used with the Shure Green bullet are Amazing!

The trick to a great traditional harp amp is low wattage so they can be driven hard and bring out the soul in the player.


The best acoustic amps I've heard are solid state.
The Trace Elliot TA100 is a great example.

Acoustic amps require a special Eq and normally onboard compression and a transparent processing. FX loop or built in Chorus / reverb is a plus. The problem with most Acoustic amps is not the amp but the pickup system used. it's very hard.. to impossible to capture the dynamics and natural richness of the wood. Most of the pickups even the $$$ end up being muddy or harsh and overly bright. _ this brings me back to the amp if you design an amp consider a way to dial out top end at the input before it gets amplified in the rest of the circuit. then a nice multi band eq or graphic to dial in the tone, with a switchable pre or post EQ fx loop.

[Reeltarded]

I like Tweed Deluxes and Bassman amps for harp. Champ works great too.. yep.

Acoustic goes direct with a great pickup rig, or not at all for me. I like mics.

[M Fowler]

I found this read one day it maybe helpful.

[ToneMerc]

a harp player looking for a different setup for his live playing.
Any suggestions would be appreciated.

Bob I've built some harps, what exactly is the harp player wanting differently? Without knowing his/her needs I can't really give a meaningful answer.

Mike

[selloutrr]

Using a Preamp like the Grace 801 and Two ribbon mics, (beyer M260, Royer 121), Condensor mics like (Schepps, and AKG C12) also give fantastic results, placed about 6" on each side of the players head at ear level gives a great natural tone and allows for some really trick panning. (fret work panned one side - the strum on the other) Only practical if they are stationary and in the studio. Live The DI is the best bet.

The Avalon U5 direct box has a great built in EQ for dialing in acoustic guitar. It's very clean and gives a nice polished tone. also wonderful on upright bass. It's not my first go to for electric bass.

If you are planning on sending any of the acoustic back to a stage monitor consider using a sound hole cover to limit the potential for feedback. due to the open body it's very easy to have run away low energy freq. (120-160hz) If the player lets go of the neck and strings are free to vibrate.

[Cliff Schecht]

I found one big thing with harp amps is the speaker. Typical guitar speakers sound like crap with harp amps. I have an old 50's Jensen C12s PA speaker that sounds killer with harp amps. Old PA speakers seem to be voiced better for harp stuff, at least from my experience and what others have posted about online. Try to find some old unwanted PA speakers, they are relatively cheap because guitar players don't care for them much and they don't sound great for most stuff. Vintage Jensen's still command a premium because of the name but you can still find old wall-mount PA boxes for super cheap that have old 12" alnico speakers which should sound great for harp.

The harp amp I built last year used a 6SJ7 input stage, two 12AX7's gain stages and an octal socket that liked EL34's but could take anything. The amp itself was a pretty bad build (one of my first) and was supposed to be a guitar amp. I found that while it sounded muddy, overdistorted and super compressed for guitar, it sounded killer with harmonica and we ended up using the amp for this at band practice for a while. I agree with the PDF that part of the magic is using a low plate voltage with larger coupling caps, but I think that the class A stage is an unnecessary "requirement". Any PP output stage can be swapped to cathode bias with a small cathode cap to get a highly compressed output, heck this even holds true for class A SE amps.


For acoustic setups is honestly best to stay simple IME. Taylors have a good live sound and are usually easy to play after a good setup. It's best to have an acoustic with a built-in under-saddle pickup at minimum and perhaps other micing methods that you can blend for the best sound. For guitars without pickup systems the LR Baggs M1/M1A soundhole pickups are great and I've heard great things about the K&K stuff but haven't tried them.

I play a 4 hour gig every Sunday night and bought a Yamaha AEX500N2 Chet Atkins style classical for the job. I do a straight fingerpicking song about every 3-4 songs (Doc Watson and old folk songs mostly) but also cover a lot of old rock, country and blues and find that with a bit of practice, the classical can sound just as good for lead as a steel string. The other benefit of playing a classical (especially this model with a great under-saddle pickup) is the rhythm always sounds spot on, even if the PA sounds goofy. Maybe not the best option for everyone but it helps me get the job done without too much hand fatigue.

[Bob S]

Thanks guys - certainly enough to get me started.
Interesting that the harp player likes the sound he gets thru a Bassman.
Not sure which speakers he uses - I'll find out.
Probably recommend solid state for acoustic.
Bit like going over to the dark side...

[billyz]

There is no reason a tube amp cannot be used for acoustic guitar. You probably don't need the over the top gain stage. Perhaps a more flexible eq would be handy but not absolutely necessary. The Speaker should be a bit more refined, or even multiple speakers with a natural crossover. For eq you might look into a Baxandale type . I used to use a B15n with an Altec and it worked very well for acoustic instruments. We plugged a Dobro, and old gibson Mandolin w a stick on transducer as well as a Taylor acoustic into it and it sounded great.

I think the main reasons SS is popular is due to the weight and cost factors. I actually think the tube acoustic amps sound better.

[M Fowler]

BiiyZ

Couldn't the impedence be increased at the input as well such as 2m2 verses the 1m for acoustic guitar or isn't that necessary? Perhaps I am wrong in my thinking here.

Mark

[billyz]

It might be useful to have a higher input impedance, but not absolutely necessary. In fact why not a variable impedance control pot, or selector. It comes down to how complex a build you want. These days I am keeping things simple. In the past I had every kind of control on a build. But in reality I did not find them all that useful. So now I just leave it out.

We were able to work with the old Ampeg circuit , while plugging in all sorts of things. The Ampeg is abit more hifi like, than a fender circuit.

I just looked at the Ampeg schematic and it does have a 2.2m load resistor on one channel and 5.6m on the other.

[M Fowler]

I just looked at the Ampeg schematic and it does have a 2.2m load resistor on one channel and 5.6m on the other.

Billy, that was my line of thinking just to have the option of two inputs but increase the impedence to 2m2 for acoustic guitar. In this case they even went higher.

Mark

[selloutrr]

most bass amps work well for acoustic guitar as long as you don't drive them hard. the down side being the weight and size. I don't recommend using a hartke aluminum cone speaker system they are overly bright.

Amps like the B-15 and dual showman work well because they were not intended to run distorted. The 15" speakers also help smooth out the bright tone end and add body to the usually thin pickup systems.

[billyz]

most bass amps work well for acoustic guitar as long as you don't drive them hard. the down side being the weight and size. I don't recommend using a hartke aluminum cone speaker system they are overly bright.

Amps like the B-15 and dual showman work well because they were not intended to run distorted. The 15" speakers also help smooth out the bright tone end and add body to the usually thin pickup systems.

I never got along with Hartke anything. Bass amps make really good Keyboard amps and Keyboard amps are really good for Acoustic instruments in my experience.

[Picker]

My favorite harp player is Jason Ricci. Amazing player and also a real gearhead. He used Fender Bassman reissues and then changed to amps from harpAmps.com which I believe are based on the Fender designs but are modded and tweaked specifically for harp players.

Hope this helps