Are any changes needed to Whammy components to OPamp roll to OPA2134? The OPA2134 data sheet looked compatible with OP2604 for voltages and pin outs that came with the kit, but I'm only getting one channel and the opamp gets hot using OPA2134.
Appreciate any thoughts
Appreciate any thoughts
Follow-up... My voltage is 16.84 an -17.05 near the max 18volts of an OP2134.
Any else OPamp roll? what mods were required? Especially interested in OPA2134.
Thanks!
read note about reg voltage
top right
for 15V rails - R9,R13=short
LEDs should stay sleaping
Thanks Zen Mod. Sounds like you're saying to us the Naked Regulator option instead of the LED option for the power supply. I see the LED option raises the regulator voltage by 1.8v.
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I jumpered R9/R13 and the power supply is now +-15vdc. Interesting after plugging in the OPA2134 only the right channel works. putting back the 4580DD and both channels work. I'll need to order a new OPA2134 incase the 2 I have are defective for some reason.I didn't check, but you said max rails are 18V for OP2134
16V8 is too close for my liking, if you leave LEDs functional
I made a typo up - sleeping, of course ....... sleaping is ......
Curious if others have Opamp rolled the WHAMMY and which one's you liked better if any changes for the better?
Yes others have, and posted their listening impressions here in this thread. It will be fun to do some reading and searching!
Finished up the Whammy yesterday. It sounds fantastic using it first as preamp, then as HPA...both ways sound incredible. I have a modest pair of Grado headphones (SR225) which were simply transformed as compare to my Creek HPA.
I have a bit off house keeping to do yet...like install the knob (can't find my metric allens wrenches), connect the LED, and close the lid. Which brings me to my question - where is the best place to take power for the front panel LED?
I have a bit off house keeping to do yet...like install the knob (can't find my metric allens wrenches), connect the LED, and close the lid. Which brings me to my question - where is the best place to take power for the front panel LED?
I used 49720, with +/-15V external power supply. Very pleased with the sound, built two already.
I made one, for my Nephew, so WHAMMY made in small workshop in Serbia is now serving enjoyment in Miami Fl.
Kudos to Wayne...... there is only one Full Nelson around 🙂
aha, yes, I did use LM833N, pulls from some unfortunate over-enthusiastic Grundig amp
it sings and behaves
Kudos to Wayne...... there is only one Full Nelson around 🙂
aha, yes, I did use LM833N, pulls from some unfortunate over-enthusiastic Grundig amp
it sings and behaves
Appreciate any ideas.
I'm hearing static on the left side which seems to ebb & flow with the music. Listening to the Whammy after AC power-off, it plays the same static in both ears as power is bled down from the filter caps to give in idea of the symptoms. No static is heard without a source playing and at full volume.
So far, I've:
Thanks for any thoughts.
I'm hearing static on the left side which seems to ebb & flow with the music. Listening to the Whammy after AC power-off, it plays the same static in both ears as power is bled down from the filter caps to give in idea of the symptoms. No static is heard without a source playing and at full volume.
So far, I've:
- Swapped R/L input RCA source cable between left to right jacks. Static remained left channel
- Replaced OP amp
- Replaced Q1/Q2 (IRF9610 & IRF610)
- Verified solder joints
- Verified proper passive components installed
- Same issue with different source DAC and different headphones
Thanks for any thoughts.
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Anyone see a problem if I were to take raw DC from the cathodes of D1 & D2 (where I measure 9VDC) to power the front panel LED?
Fixed it!! Somehow talking it out loud typing the problem, helped me think through the issue. The key was the similar static on the right ear when powering down. I grabbed a 1K dale from another project and mistook it for two of the 10K Dale's surrounding the left side optocoupler.
All good!
Thanks guys!
I took mine from the junction of R37 & C6 from the underside of the power supply. Also used a 20K resistor in line with the LED encapsulated in red heat shrink tube. wire runs under the PCB looks neater.
In the end, as recommended in this thread, I connected the anode of the LED to R10 and the cathode to R9 (pads on both towards the front of the PCB). Seems to work fine…although not as tidy. I used a 10K resistor and a blue LED. Thanks for the suggestion though.
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