Bottlehead Forum
Bottlehead Kits => Moreplay => Topic started by: Dzrout on February 09, 2023, 07:55:50 AM
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I have my Moreplay feeding a pair of Monoblock tube amps and the second output is going into an EQ then a solid state amp. I never use the power amps together, I only power on the one I want to use when I want to use it.
My Moreplay seems to sound better, clearer, and louder on my tube amps when the solid state amp is physically disconnected, even when powered off.
Is this expected behavior? Or am I crazy?? Lol
As I’m not using them at the same time, would it be best to put a disconnect switch on the second output?
Thank you for the help! As always!
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If the eq has a low input impedance, then yes, this is normal.
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Thank you. Listed at 47K.
What are your thoughts on switching the outputs. I could imagine that when I’m listing to my solid state amp, it likely also has some negative attributes related to the tube amps being connected.
As I only listen to one at a time, I just assume have the one I’m not listening to be disconnected from the circuit.
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Figure I could use a 4PDT toggle switch to switch between them.
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I've never heard of this problem and it doesn't make sense. To make sure you aren't imagining it, you can experiment by listening to music on your tube amps with your eyes covered while someone else repeatedly connects and disconnects the cables going to the EQ. The eye covering is to make you blind to what your assistant is doing. Holler whenever you think you hear a difference, while your assistant takes notes.
I assume your EQ is off anytime the SS amp is off.
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I left the volume knob alone, played a song and looked at my SPL Meter. Got up to 104.5db.
Connected the powered off solid state amp. Replayed the song, got up to 89.5db.
Also had noticeable distortion with the second amp connected.
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47K is not a low impedance, and 15dB is 10 times more change than expected.
Does the problem persist if the equalizer is powered up? Some solid-state gear presents a low and nonlinear input impedance when turned off, but a reasonably linear impedance when running.
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I will try tomorrow. When it’s off, it’s supposed to be passive. I can play through to the amp. I can test tomorrow if there is any difference when it’s on. Thank you.
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How about leaving the ss RCA connectors unplugged until you want to use them?
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I’d rather switch them. It’s worth it for the convenience.
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47K is not a low impedance, and 15dB is 10 times more change than expected.
Does the problem persist if the equalizer is powered up? Some solid-state gear presents a low and nonlinear input impedance when turned off, but a reasonably linear impedance when running.
So I measured it, when the EQ is turned off or in “flat/Passive†mode, it measures 7k Ohms.
So that’s likely the issue.
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Just remove the EQ and connect directly to the SS amp. See if the problem persists.
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For what it's worth, the BeePre with the second upgrade would tolerate this kind of abuse.
I'd still probably rib the manufacturer of the EQ a little bit though. 7K is a pretty low input impedance for a line level component.
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I do have a PreBee also. But I like the sound of the Moreplay more. Thank you for your help.
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So I added a 4PDT switch so I can switch between the outputs as desired, safe to assume I can remove the 220ohm resistor that was “between†them. As now they are working independently? Thank you.
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Yes.