modify a fender hot rod deluxe

choochoo53 · modify a fender hot rod deluxe

I'm hoping for some help on modifying a current amp of mine towards being harp friendly. I don't have the cash to go out and purchase an amp thats more harp specific right now. I own a Fender Hot rod Deluxe and would like to modify it and get it as close to harp friendly as i can. Tnaks to all for listening.

Charlie

jbone

the hot rod delux is the second amp i ever bought, back in the early 90's. my only harp mic was a stock shure green bullet, the kind with a "good" cm element, which was very hot and sensitive.
i let a guitar player talk me into that amp and to me it was a mistake. but that's not the end of the story. back then i knew nothing about amps except this one would feed back when i tried to keep up with the band volume, which was about twice what it needed to be. i put a 12au7 in the pre amp socket and it helped some but eventually i just went back to the trusty princeton and miced it through the p.a. still not the end of the story!
a few years ago i met a harp guy who was running the exact same amp for harp- a delux- and it cut through well and the tone was pretty good too. on a break i asked him how he got it to come up on volume without such a feedback nightmare, and he wouldn't really tell me. but i read someplace that with a 4-power tube amp, you can remove 2 power tubes and cut the power, which will actually bring the useable power up.
since i haven't got a delux to experiment on, i have no way to verify this, but someone somewhere on the net has the answer. speaker swap may be part of it too.

i will say this- 40 watts and a single 12" speaker is not a great combo for harp without some serious mods taking place. brian purdy at harpgear amps would likely be a good one to talk with about the delux. or steve clark at sligo ampsdotcom. greg heumann, who posts here often and is a mic building master, may have some good insight also.

i'll take one more guess here, that's to get several 12a class tubes, like 12au7, 12at7, 12ay7, and try different combinations of them in your pre amp section. there are 3 sockets and with the 12ax7, 4 tubes you can try. it may take a day of swapping tubes but ultimately you will find a decent combination of volume and tone. i use a 12au7 in slot 1 on the silvertone amp and it boosted useable volume without losing tone much at all. i use 2 12au7's in the bassman, in slot 1 and 3, and it has cut feedback a lot.

one other thing comes to mind. on some fender circuits, if you turn the treble all the way up, it actually turns it off. since the high freqs are where feedback occurs, you might try that also. a kind of rule of thumb i use on a harp amp is, highs off or way down, mids a half, bass about 2/3 up, NO presence, NO hot channel, NO reverb. master volume is another story, the relationship between channel volume and master can be tricky. some say, crank the master and set actual volume with the channel volume, others say the opposite.

and- i wonder exactly what mic you are using? the relationship of freq response of a particular element and the amp it's going into is a crucial factor to consider. a cm is the hottest element i know of. i use one often in my silvertone 1482 and my replica bassman. a crystal element is not as hot, much cleaner, but lacks the low end punch a lot of harp guys want. i use one of these also, most of the time. a ceramic element is similar to a crystal but to me, not as sweet tone wise.

so you have some questions to answer and things to try out. and some people to ask for advice too! hope this helped and good luck.