I dig that maxed sound you got there. Definitely OD+, but still this side of in-you-face, and very percussive. Nice job.
Enjoy the benefits of a premium membership!
Upgrade Account
-
TalkBass has been independent since 1998. Add your voice.
Create a free account to reply to discussions, view embedded media, and browse with fewer display ads.
Join free Log in
Want zero display ads or expanded classifieds tools? Compare plans.
Ampeg Fliptop in a stompbox......The Flipster.
- Thread starter Vin_MM_Sabre_79
- Start date
So... you're using it to drive your power amp. I have some questions for you!
I get a lot of questions like this: Will the Flipster drive a power amp?
It certainly drives this guitard's
power amp (MosValve rack power amp). As I was told by a helpful member of this forum, a power amp like a QSC requires 1.5v-2v or so at the input to reach full power. So, I measured James' Flipster and found 2.9v-3.1v at the output (master volume at 11).Can you verify that the Flipster does, in fact, have the power to drive a power amp?
Thanks!
Mark
bongomania
Commercial User
I should be done with my build in a couple of days, at which point I will definitely try using it to drive a Carvin power amp.
Mark,
I use a Yorkville AP800 power amp, and I will make sure to try my Flipster with it to see how it works.
Lyle
Hey guys if you are capable using an soldering iron then drop me a pm and I'll send you the stripboard version I got of this beauty. It's very simple to build.
Not exactly a clinical trial- but when I was recording those grabs I tried going from the Flipster straight into the laptop Mic-in but it wasn't a red hot signal. I ended up taking those recordings out of the Aggy effect send.
I'll experiment with it later but I think the answer is - yes you could do it- but wouldn't be a substitute for a fully fledged preamp.
It drives my poweramp just fine (I keep the volume around 1:00). I use a Crown XLS802D and it wants 1.25 volts. QSC poweramps are insensitive poweramps (they never call you back 
) and they need a lot of input compared to other poweramps.
@ Bongo: I'm nearly positive the input sensitivity for the Carvin poweramps is like 1 volt so I think you're set
) and they need a lot of input compared to other poweramps. @ Bongo: I'm nearly positive the input sensitivity for the Carvin poweramps is like 1 volt so I think you're set
bongomania
Commercial User
I completed my build last night, yay! Now it looks like I get to spend some time troubleshooting. 
I was puzzling on the best way to add a DI out, and I am fairly sure it would involve building a separate little circuitboard with a transformer. Then you'd want to split the normal output of the effect in two, with separate level controls per output.
I was puzzling on the best way to add a DI out, and I am fairly sure it would involve building a separate little circuitboard with a transformer. Then you'd want to split the normal output of the effect in two, with separate level controls per output.
I completed my build last night, yay! Now it looks like I get to spend some time troubleshooting.
I was puzzling on the best way to add a DI out, and I am fairly sure it would involve building a separate little circuitboard with a transformer. Then you'd want to split the normal output of the effect in two, with separate level controls per output.
Yeah. Invalid Link Removed looks good.
Its a pretty easy debug as the circuit has distinct stages. Wherever the error is will have a failed V reading at the fet drain. I had a 220K instead of a 220R in mine. didnt read the schem carefully.
Lemme know if you need
.
bongomania
Commercial User
Actually, I could use a clue. Here's where it stands:
9VDC confirmed at the + power terminal.
~6.5 VDC at all four FET drains, with a pretty wide range of adjustment.
Bypass works perfectly.
Engaged, the LED comes on, but the signal level drops to "barely there", with a loud ground hum.
Obviously that could point to a grounding issue, but I haven't found any missing or poorly-soldered ground connections (yet). Any suggestions?
9VDC confirmed at the + power terminal.
~6.5 VDC at all four FET drains, with a pretty wide range of adjustment.
Bypass works perfectly.
Engaged, the LED comes on, but the signal level drops to "barely there", with a loud ground hum.
Obviously that could point to a grounding issue, but I haven't found any missing or poorly-soldered ground connections (yet). Any suggestions?
bongomania
Commercial User
Yeah, I got a chance to audio-probe it tonight. Turns out the faint signal I was hearing when the effect was engaged was actually leakage through some part of the circuit; it was audible without using the probe. When I cranked all pots to max, the leaked barely-there signal did sound like a distortion effect, so I am guessing the signal is making it into the FETs but there's a bad connection between them and the output. However, here's the weird part: I can't find any signal (distorted or otherwise) anywhere on the board when the effect is engaged.
The FETs are all at appropriate drain voltages as noted, and I've been squinting through a magnifying lens at every solder junction with no sign of a gap or cold joint. I haven't done the continuity testing yet, I guess that's next.
The FETs are all at appropriate drain voltages as noted, and I've been squinting through a magnifying lens at every solder junction with no sign of a gap or cold joint. I haven't done the continuity testing yet, I guess that's next.
Does the signal decrease as you progress through the fets?
This circuit is apparently very sensitive to unclean power supply, So if you're not using an audio quality PS you will want to filter the DC line. I suggest a 100r resister to the pcb and a 470uF Cap to ground. That way you can plug it into whatever 9V rubbish you have lying around.
This circuit is apparently very sensitive to unclean power supply, So if you're not using an audio quality PS you will want to filter the DC line. I suggest a 100r resister to the pcb and a 470uF Cap to ground. That way you can plug it into whatever 9V rubbish you have lying around.
bongomania
Commercial User
I'll experiment with the FETs more this evening, but I was using two different regulated supplies, a Boss and a Voodoo PPII.
Sounds like grounding to me 
I always use a battery for testing, just a good idea.
Try VERY LIGHTLY twisting the circuit board around, while listening to it. Little trick for checking for cold solder joints. I've also had great success with Invalid Link Removed
My build took forever, I forgot to connect the jfets to the trims .
I always use a battery for testing, just a good idea.
Try VERY LIGHTLY twisting the circuit board around, while listening to it. Little trick for checking for cold solder joints. I've also had great success with Invalid Link Removed
My build took forever, I forgot to connect the jfets to the trims
.
(pedro makes mental note NOT to read about the flipster while at work and unable to listen to sound samples. Check watch and notes 'quitting time' is near.)
