Back Story: Played a Fender Champ 600 this past weekend and thought it sounded awesome and got me thinking about speaker size and basically gave me a case of "Amp Fever". The easy solution is just to probably buy myself a Champ, but in the nature of a harmonica player I need to complicate things so...
Amp: I own a Hilgen T-1506 (Troubador) that has one 12" speaker. ***Amp Details Go Here When I Get Home***. It's an oddball amp and I've never seen another one personally. I'm not sure if it's really "worth" anything beyond my own sentimental value.
Objective: Possibly put 2 6" speakers in place of the current 12" speaker in the hope that it will make the amp super awesome.
I will get pictures of it and post up for analysis and general gawking. Is my premise completely flawed? Are there a MILLION other things that need to be considered?
Here's a pretty good representation of what mine looks like:
Last Edited by on May 10, 2011 10:03 AM
I'm not a pro in tube amp but I do know some stuff. If you really want to alter the sound of a tube amp you really want to change the properties of the preamp section of the amp. Changing cathode resistor on preamp tube, removing bypass cap, stuff like that. All this to change the region where the tubes operate and to really affect the tone of the amp.
Changing speaker will also affect the tone but not THAT much.You really are only reproducing the signal amplified by your amp witht he speaker. So the signal coming out of the amp is really what defines your tone the most.
I prefer 10 inch speaker in harp amp but this is only a personnal taste. Changing from 1 12" to 2 X 6" might change the sound a little and push a little bit more air but I don't think it will make a drastic difference tone wise.
Anyway if you do have those 2X6" speaker already in your possession sure try it just to see but just make sure you match the correct impedance of the output transfo. If your amp expect an 8 ohm load you can either wire 2 X 16ohm speaker in parallel or 2X 4 ohm speaker in series.
If you don't have them cheap or already I'm not sure it's worth the investment.like I told you i'm not a pro so feel free to prove me wrong anyone :)!
I have amps with small speakers and a single 12" speaker. If you want it to sound better or different. I would do what tonyh said. From experience I believe the 12" speaker will sound better than 2 6" speakers. Now it makes a huge difference what speakers you are swpping around! I had a 6" zenith speaker from a 60's TV. Man that thing sounded great in a home 6v6 amp I built. After acouple yeras of playing at 12 it quit on me. I never got the amp to sound right after that. So the right speaker for what you want is very important. I usually go from smaller to larger speakers when ever changing a configuration. I just like the sound quality of larger speakers. I would bring it to someone that knows what to do! Your speaker might not be very good! It looks like a cheap amp and alot of manufactures cut corners on many things back then. Some one that knows what a good amp likes like might be able to turn that thing into gold for you easily! Just an idea! I would try that before cutting it up. It might not be worth much, but it does look cool.
Last Edited by on May 18, 2011 8:22 AM
I've had the amp since I was approx 15. I'm 25 now.
It works fine and it's definitely had work done to it as I really start looking at it (Two prong power cord swapped for a 3 prong ground plug, power knob replaced with power switch).
It has two 12ax7 pre-amp tubes, one of which I swapped with a 12au7 several months ago which really helped with the playability of the amp (I used to hate it) and I can actually turn the volume up to the point where it starts to break up a bit.
If I were to bring it in for a check-up, where would be a good place to start? I'm right outside Boston. I've been told "Cranky's" in Mansfield, MA is THE Man when it comes to amps.
I would concentrate on speaker. Try a different 12 or go to a nice Weber 10 Ferromax. I prefer the 10 over the 12 almpst every time for harp. For some reason I have never had a 12 that sounded good with harp. @x6 would be rathewr thin iI believe.
Hmmm if it were me I'd play with some more tubes. Dropping from an AX to AU is a bit drastic. You might get an AY and an AT and experiment some more with it, trying the AX in either slot, etc. Some old amps have lower voltages on the preamp already and aren't as gainy with AX's as Fenders, dropping to AU makes them lame. Just my 2 cents. You have nice tone!
Joe, thanks for the compliment and the suggestions! I'm just kind of becoming an "equipment guy".
Where's the best place to educate myself on the nature of different tubes... or should I just buy two AYs and two ATs and experiment with configurations?
I'd just get one of each and play around with it. Also the Champ is single ended and yours is (probably) not. That might be what you dig about the sound of it. Speakers/tubes won't give you that. But Lone Wolf has a pedal you might like called the Harp Octave. It puts out some pleasing harmonics like that, check out the demos on LW's site-
I like the amp with the RE15. I like a smoother tone that breaks up when pushed. I would not fix what is not broken. I like your tone and I like your playing. Very impressive! ----------
Alright, so a question about tubes. I took the amp apart slightly last night to see what kind of tubes were in it...
Preamp: 1 12AX7 Mesa, 1 12AU7 Electro Harmonix (put in by me). I swapped out the 12AU7 and put it back "stock" with a second 12AX7 and was pretty happy with how it sounded... I recall having alot of feedback with this setup, but didn't seem to be the case.
Power: 2 EL84M Sovteks
Unknown: Didn't have a brand, can't remember the model#... something like 5GYT or YGT. Pretty sure this is connected to the built in Tremelo. I recall it had 5 metal pins and 1 center plastic guide pin with a notch in it.
Would there be any value in considering different power tubes? From what little reading I've done, looks like I'm stuck in the EL84 category.
5Y3 is the rectifier (feeds dc to the rest of the tubes, it does not work the tremolo), stick to NOS US manufactured tubes, the Russian Sovtek is a good tube in its own right, but not suitable as a drop in replacement for lots of old amps.
EL84M Sovtek are very sturdy, they are also a higher W rating (13.5W vs 12W dissipation, not power output) so are a safer bet if you just tend to drop tubes in without checking bias. Feel free to try other brands (of EL84/6BQ5), watch for any red/orange glow on the plates (bad), 6BQ5 is the US designation for EL84.
Preamp tubes, see if subbing one of them affects the trem, my guess is one half of one of them does, probably the one furthest from the EL84, but that's an educated guess only...the tube next to the EL84 is most likely to be the phase inverter & splits the preamp signal into 2 differently phased signals to feed the power tubes...no science or theory really helps with selecting preamp tubes, by ear is the best way. Amplification factor (AX=100, 5751=70, 12AT = 60, 12AY = 44, 12AU = 19) will probably be more critical to tone than brand of tube, e.g. if a 12AU sounds best, then no 12AX7 is going to do the same job.
Last Edited by on May 17, 2011 1:08 PM
