Donate to This Project

Your donations help us continue to add new and exciting features. Please consider making a donation

HarmonicaSpace is a subsidiary of Brady Mills Graphics

Optimal tube configuration

Back to the Gear Room

Adam P
Jun 11, 2011 5:08 PM GMT

Hi Guys,

I'm looking for some advice about amp mods and specifically tubes. I've just picked up a new Peavey Delta Blues 210 amplifer. I realise it's not necessarily the best amp for harp but I got it for a great price and I'm pretty happy with the tone I'm getting from it. My worry is feedback. It also gives off quite a hum at low volumes. I was wondering if swapping the tubes out might make it more suitable for harp. It's currently got 4 EL84 power tubes with a 12AX7 driver and then 2 12AX7 pre-amp tubes.

I know almost nothing about amps, tubes etc so would appreciate any advice. Would an anti-feedback device like the Kinder or would something like the Lone Wolf Harp Tone + help?


Share |

Comments (6)

Login or Register to Post Comments

Order by Date

Jun 12, 2011 5:46 PM GMT
walterharp Replied:

there are a few mods possible.

first thing wouldbe to try 12ay7, 12at7 or 12au7 tubes in the preamp section.

harp players llike a 12dy7 in the third position which puts the power tubes a little out of synch and gives a dirtier sound.

try over on the lone wolf forum, they are pretty knowledgable about amps classic30 mods.pdf

Jun 13, 2011 8:15 PM GMT
Adam P Replied:

Thanks for the replay walterharp. I've ordered a couple of 12au7s to try out. Fingers crossed.

Jun 13, 2011 8:16 PM GMT
Adam P Replied:

Every time I type 'reply' it get's changed to 'replay'. That'll teach me to check my posts before sending.

Jun 16, 2011 11:53 AM GMT
Jawbone K Replied:

i'm not real familiar with power tubes, but when i had a 210- probably just like yours- i found that the 12a class tubes needed reconfiguring. my final setup- i THINK- was p1, 12ax7, p2, 12au7, p3, 12au7. the idea being, let the hot signal in via the 12ax7 (which does not cut gain at all) and then let the 12au7's (which DO cut gain) tame the feedback.

i liked the 210 for harp and wish i could have kept it.economic reality forced me to let it go. one thing i liked was the speaker out jack. i could run a different cab with no hassles.

i use that tube config in both of my gigging amps, a silvertone 1482 (12-15 watt, single 12) and my bassman replica (40 wat 4x10), and it works well. more so in the bassman where i can really crank up if necessary and no doubt be heard.

one thing to remember is that between the various classes and values of 12a series tube, and 3 pre amp slots, there are something like 10,000 possible combinations one could try. what works for one amp may not in another.

Jun 16, 2011 11:16 PM GMT
Adam P Replied:

I've just got back from my latest band rehearsal, the first with my new Peavey Delta Blues. After trying a few different combinations I ended up swapping the 12AX7s in positions 1 and 3 for 12AU7s and I'm pleased to report my feedback problems are now a thing of the past (unless I try to crank the volume up above 8 or 9).

To my ear, the amp sounded great and the rest of the band were pretty positive as well. I could even hear myself clearly (most of the time).

Thanks again for the advice.

Jun 21, 2011 12:04 PM GMT
Jawbone K Replied:

fait warning- cutting the gain will cut some power esp if the p1 tube is changed to a lesser value. tyhis translates to less volume out live. if your band mates keep their volume within reason this is not an issue. my experience is, as the night wears on the volume creeps up. i'd say even with the tube swap, have a mic ready to go into the p.a. if the creeping volume disease is present.

© 2009 HarmonicaSpace

Advertise with Us | Terms and Conditions | Privacy Policy | Anti-Spam Policy | Report Abuse | Report Problem | Contact Us

Harmonica Space offers free social networking, harmonica forums and harmonica chat for harmonica players.
Join today and meet other harmonica players from all over the world!

Web Development and Web Design by Brady Mills Graphics