Mark Johnson = The Brilliance.
I'm game. Doesn't matter where the pot is in my builds, there's nothing to hear unless the source is playing. I'll swap one with you. PM me. Have you poked around inside with a chopstick to see if any connections are questionable? I seem to remember some shhhhhhh-ing in one of mine that I tracked down to "about to break" leads from pot to board—a flying lead version, not soldered to board as designed...
This mod? See pic. I did that to keep the voltages within the Burson spec per some of the previous posts in this awesome thread. The amp was quiet before though... so that's probably not helpful! My other amp—the one I'd send you—doesn't have that mod... it's ghostly—can't really use the term "noise floor" with it....post some interior pics of your build...
Attachments
Technically under the schematic spec... but been working out just fine—and easy access for opamp rolling...(I'm not sure if they made it into the new/forthcoming chassis parts makeup kit...)
https://www.mouser.com/ProductDetail/Nichicon/UMW1E101MDD?qs=kArNe9LFxXkosx5ETM19rg%3D%3D
https://www.mouser.com/ProductDetail/Nichicon/UMW1E101MDD?qs=kArNe9LFxXkosx5ETM19rg%3D%3D
Great point... I've been wondering what the size requirement will be for caps in that position as it relates to the output jack on the new chassis.
This is really interesting. I was sent both the V6 Classic and the V5i to try out on the WHAMMY. I have delayed a review because the V5i does not work as expected. It gives out some weird "robot like" sounds... remember the drone that lands on Hoth on Empire Strikes Back? That kind of sound. The V6 is DEAD SILENT!
If I click the top of the Burson's metallic casing, I can "change" the blip's characteristics. So there is something amiss. Also, I mentioned I have an 18V rails (led reference regulated PSU) and it was mentioned here that it would be a little less on the rails of the OpAmp, so that "I was good to go".
So, I am looking at fixing and really "trying" the V5i, so I installed a 0.1uF between pins 4 and 8, but I don't it made any difference.
You have gone much higher with 0.33uF. I don't think I have those at hand, but I would measure the V rails properly and see if this could be the source of my problems.
I'm following this discussion with interest!
Rafa.
Hey Rafa, you were the one that turned me onto the cap mod to bring the voltages into spec. At the time I was unaware of the Burson voltage requirements. I ran it without that mod for days, and really only did it to make sure it was good for the long haul since I really like it. I too evaluated the V6 and V5i. Much preferred the V5i! But they are both great—my sorta mini review is many pages back in this thread. No issues with weird noises with the V5i....Perhaps you need them to send you another for eval? I had the .33 on hand... not sure it would make a huge amount of difference?
I remember very vividly the conversations and your review, that is what actually encouraged me to ask for the V6 Classic and the V5i instead of the V6 Classic and V6 Vivid, because of your preference. Alas, I was never able to truly compare them.
For full disclosure, they approached me and sent them for eval / review, so I don't feel I am entitled to ask for "another" sample. If it works with some adjustments, great, if not, I'll review the V6 as a standalone product.
Regrettably, I don't have another equipment that uses an OpAmp where I could test it. Maybe I can create a small test bench to see if the issues reside within the specific V5i I have or if it somehow related to my Whammy implementation. I did not install C2 and C7, maybe that could make a difference?
Still, I am hesitant to install extra things to try a particular OpAmp when others seem to shine without that. So, yeah, all possibilities and alternatives that are part of the fun of these endeavors.
For full disclosure, they approached me and sent them for eval / review, so I don't feel I am entitled to ask for "another" sample. If it works with some adjustments, great, if not, I'll review the V6 as a standalone product.
Regrettably, I don't have another equipment that uses an OpAmp where I could test it. Maybe I can create a small test bench to see if the issues reside within the specific V5i I have or if it somehow related to my Whammy implementation. I did not install C2 and C7, maybe that could make a difference?
Still, I am hesitant to install extra things to try a particular OpAmp when others seem to shine without that. So, yeah, all possibilities and alternatives that are part of the fun of these endeavors.
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On the plus side of "installing extra things to try a particular OpAmp...", I believe decoupling caps for opamps are a common practice. A 0.01uF or 0.1uF shouldn't be an issue with any of these common opamps, right?
Would love to hear an opinion from someone would argue it could be problematic
Would love to hear an opinion from someone would argue it could be problematic
Lower gain = hiss?
I wanted to experiment with lower gain since I'm only at 9 o'clock on the pot before it's too loud (plus, if you don't need the gain with your source, why increase the noise floor, right?)
When I swapped R12 to a 4.7K, I noticed only the left channel was quiter, but had hiss no matter the pot level
I noticed R1 was the complementary on the other channel, I swapped that and same thing -- quieter right channel but hiss present no matter the pot level.
C2 & C7 made it worse. This was with an OPA1612 btw.
Am I misunderstanding how to lower gain (increase R12 value)? Thanks in advance for tips
I wanted to experiment with lower gain since I'm only at 9 o'clock on the pot before it's too loud (plus, if you don't need the gain with your source, why increase the noise floor, right?)
When I swapped R12 to a 4.7K, I noticed only the left channel was quiter, but had hiss no matter the pot level
I noticed R1 was the complementary on the other channel, I swapped that and same thing -- quieter right channel but hiss present no matter the pot level.
C2 & C7 made it worse. This was with an OPA1612 btw.
Am I misunderstanding how to lower gain (increase R12 value)? Thanks in advance for tips
