How come this didn't work? (powering an EH Holy Grail)

[sengo]

Hey guys,

I just received an EH Holy Grail in the mail I bought from Ebay... and of coarse there's no wall wart with it. I did some searching and found other people have been able to power it with a 9V battery, so I tried this, and the thing just squeals when I try to use it. The squel gets louder as I turn the knob for more reverb.

Any ideas of why it's doing that? I'm really hoping it's not a bad pedal, I bought it from a reputable seller.

I'll probably go out and buy an AC adaptor tomorrow and try that, its just that I want to use it NOW! 

Any ideas?

Thanks,

Nick

[oskar]

http://www.ehx.com/instructions/HOLY_GRAIL_INSTRUCTIONS.pdf

It says 9V allright but at 500mA and that is a lot for a 9V battery, especially if it isn't absolutely fresh. It
probably loads down your battery beyond what it needs.

oskar

[theehman]

I just fixed a couple of them for a customer and I remember the actual current draw was about 200mA.  Still too much for a battery, which is why they don't have battery clips.

[scaesic]

could you not stick two 9v batteries in parralell though?

[sengo]

Ahh, that is actually a great relief.

I was worried it was just broken.

I'm going to try two batteries in series and see how that goes.

It's alright to use any wall wart as long as it's 9V right? If I one rated at a higher amperage the pedal still only draws what it needs correct?

[Papa_lazerous]

I'm going to try two batteries in series and see how that goes.

Nooooooooooo not series!!!!!

in parallel!!!!! if you do it in series with 2 batterys you will have 18 volts 

[sengo]

Quote from: sengo on Today at 07:36:52 PM

I'm going to try two batteries in series and see how that goes.


Nooooooooooo not series!!!!!

in parallel!!!!! if you do it in series with 2 batterys you will have 18 volts  icon_rolleyes

Haha, I misspoke. 

[Papa_lazerous]

I'm glad you didnt type that and then actually go and do it lol  that would not be funny, well not for you anyway

[sengo]

I found a 9V adapter but it's output is 2.2 amps. Is that usable?

[Papa_lazerous]

well it needs to be a 9volt 500mA supply so more amps cant hurt. Just make sure polarity is ok

[cheeb]

I found that there's a faint squeal (enhanced by boosters and overdrives) that persists whether a Holy Grail is bypassed or not any time it's connected to ANY 9v adaptor (including One Spots) other than the E~H adaptor that is intended for it. I dunno why, but those are only like $8 USD. I tried batteries, other wall warts, everything I could think of, and the problem was only solved by buying an E~H wall wart.  Just my experience.

[remmelt]

Oh REALLY??? I've tried all kinds of caps with my power supplies (one spot, regular cheapo off the shelf ones, anything) and it always squeals. The sound is right though, so I still use it. But if you say it needs an EH adapter and that will fix it, I wonder what's in those adapters? Voodoo parts?

[StickMan]

I'm looking at building a footswitch unit for a new amp a friend is making for me, and it's also going to control some of the FX loop functionality as well.  Constraints on the space inside the canabalized chassis that we're using limited the design to either having a properly buffered FX loop or an onboard reverb.  I went with the FX loop, and picked up an HG to in the FX loop.

My plan is to re-house the HG in the footswitch enclosure, and we're looking to see if there are enough DC hookups inside the amp's power supply to run a 9V hot wire through the footswitch cable (it will be five conductor with DIN connectors) to power the HG.  I was thinking 200mA, but I'll need to let him know we should try for 500mA if possible.

[sengo]

Well, it works, all is good.

There is a definite hiss, but I have read that was a common problem with the Holy Grail. I guess I'll have to pick up the true EH wall wart eventually.

Any comments on how the HG handels a fuzz in front of it? I heard a lot of distortion boxes don't work too well with it, but that was just one persons opinion.

Nick