There is talk about that. The original owner sent this one back to Dave. As I recall he put in larger heatsinks and set the fan up to be always on. I got a 3 space case as well for some extra circulation. I have never had a heat issue.
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Thunderfunk Amp club!
- Thread starter Neatcirrus
- Start date
Still crankin away on my 420. It plays wonderfully well with every bass I own. And that timbre knob is just plain magic when it comes to tweaking the tone to fit the room dynamics.
I've often wondered if I should step up to the 750 or 800. I'm not really in need of any additional power but headroom is always good to have. Are these voiced the same as the 420 or should I search for a 550 instead?
I've often wondered if I should step up to the 750 or 800. I'm not really in need of any additional power but headroom is always good to have. Are these voiced the same as the 420 or should I search for a 550 instead?
I've owned a 550 for many years and tried an 800, didn't really like the tone. IMO, the Bergantino B-Amp sounds more like a louder TF-550 than the TF-800!
EG
Nice rig! I used to run two Acme cabs and a TF-550, but it wasn't really powerful enough for the cabs, as they aren't very efficient. (But sound good!)
EG
EG
Does it have the gold dot on the back by the S#? If it does it has the updated 800 watt specs and improved cooling!
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Just a head's up, thought I'd mention this. I have a 550B and it is and has been my #1 for many reliable years. Last year at rehearsal I get set up and...nothing. All the usual, cable check etc....squat. It kinda pissed me off being so bullet proof for so long I employed the traditional final triage to electronic gear and banged it.
And it came back! Sounding dirty and under powered but it got me through rehearsal. Glad it wasn't a gig.
So off it went to my good friend the electronics wizard. The problem was a connection at the effects loop had come loose. Apparently not that uncommon in older gear. He tightened them up and made a suggestion since I never use the loops. Do it once and never worry about it again.
And it came back! Sounding dirty and under powered but it got me through rehearsal. Glad it wasn't a gig.
So off it went to my good friend the electronics wizard. The problem was a connection at the effects loop had come loose. Apparently not that uncommon in older gear. He tightened them up and made a suggestion since I never use the loops. Do it once and never worry about it again.
My TFB-750A developed a "popping" while operating. I know Thunderfunk is out of business, but before I give up on the head, does anyone have access to a schematic? I have a shop that will look at it if I can get a schematic
My 800 developed a popping... basically sounded like when you flip the SS/Tube switch - you get just a little electrical pop.
I'm pretty good with troubleshooting, and figured out it wasn't a bad cable, or electricity, or what ever.
The popping was happening regularly every so many seconds (like every 15 seconds).
I had a local guy try to fix it - but no dice.
Then I had a pretty strange experience trying to get Dave at Thunderfunk to fix it. I went through a series of weird communications with him. First he told me it must by my cables, my cab, etc... Then, when I shipped it to him (on my dime with packing, etc...), he told me there was nothing wrong with the amp. At one point he told me that he pounded on the transformer with a rubber mallet and no matter what he did, he couldn't get the amp to make a sound... just dead quiet / no repair necessary. Can't remember, but I'm sure I paid a bench fee to have him pound on it and tell me there was nothing wrong.
I ended up selling it. As far as I was concerned, the amp was not usable with the popping, and since he told me he didn't do anything, then I wasn't willing to have him send a broken amp back and go down some rabbit hole of getting it fixed, or trying to sell a broken amp.
I finally got him to agree to that I would sell it, and he would guarantee the amp was in perfect working order for the buyer, and he shipped it to the buyer direct from his shop. The guy that got it said it worked fine. ---very strange---
I know my post doesn't help much, but maybe here...
Thunderfunk TB550-B Schematics
I'm pretty good with troubleshooting, and figured out it wasn't a bad cable, or electricity, or what ever.
The popping was happening regularly every so many seconds (like every 15 seconds).
I had a local guy try to fix it - but no dice.
Then I had a pretty strange experience trying to get Dave at Thunderfunk to fix it. I went through a series of weird communications with him. First he told me it must by my cables, my cab, etc... Then, when I shipped it to him (on my dime with packing, etc...), he told me there was nothing wrong with the amp. At one point he told me that he pounded on the transformer with a rubber mallet and no matter what he did, he couldn't get the amp to make a sound... just dead quiet / no repair necessary. Can't remember, but I'm sure I paid a bench fee to have him pound on it and tell me there was nothing wrong.
I ended up selling it. As far as I was concerned, the amp was not usable with the popping, and since he told me he didn't do anything, then I wasn't willing to have him send a broken amp back and go down some rabbit hole of getting it fixed, or trying to sell a broken amp.
I finally got him to agree to that I would sell it, and he would guarantee the amp was in perfect working order for the buyer, and he shipped it to the buyer direct from his shop. The guy that got it said it worked fine. ---very strange---
I know my post doesn't help much, but maybe here...
Thunderfunk TB550-B Schematics
Wind forward a few years.... I recently did a direct comparison between my TB-550 and my Berg B-Amp and they sound nearly identical through the same cabinet. The B-Amp has a tiny bit more "presence" and treble, but all the low-end and mids sounded the same to me.
EG
EG
I've only played a Berg amp in a store... but I get that comparison.
I used to have a Quilter BB800, and I thought it had very strong T-Funk vibes as well.
And not that there is much to be done but my Thunderfunk 420 has begun acting up in exactly the same way. When the amp experiences any vibration at all it pops in and out. It is good to have the schematic, of course, if I can find someone to work on it.
Good luck.
Mine never wen't in and out (as in lost sound),,, just an electrical pop.
Anyway,,, good luck. There are still dudes out there who know how to work on amps. One of the best, so it may be worth it.
Well, I believe it to be a similar issue to yours as the popping is accompanied by a loss in volume and popping again as it comes back in. Sometimes it loses sound completely and sometimes it's just very quiet with an egregious loud pop. After some time of it behaving this way if I slap the top of the amp it ceases to be a problem for a short time. It does tend to be less of an issue if I do not play with the amplifier on top of the cabinet but on a separate adjacent static cabinet. Initially I did not try to slap the top of the amp until I couldn't get any sound out of it at one point.
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Yep. The only slap I have done over the decades was to old TV's. Lucky my 550 has not needed that yet.
