Output attenuation

Dzrout · 4216

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Offline Dzrout

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on: January 26, 2023, 06:00:28 AM
Can I attenuate the second output on my Moreplay a bit by changing the resistor between the 2 outputs.

I have my second output going to a newer amp and it is so loud i have no range on the volume pot.

I don’t want to change the output on the first set as those work good with the amp that’s on them.

Any thoughts on value if I want to attenuate maybe 6-12db?

Thank you



Offline Paul Birkeland

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Reply #1 on: January 26, 2023, 06:05:21 AM
That's not really what those resistors do, and you'd have to use a very high value to accomplish that and it would depend on the input impedance of the amp that's too loud.  This would add to the output impedance of the preamp, which isn't ideal.  The Moreplay has very, very low gain, so I would wonder what amp and speakers are causing the problem?  You could probably get away with the Rothwell attenuators at the input of the second amp, but I would suggest posting a more complete picture of all of the components (speakers included) being used here.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Dzrout

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Reply #2 on: January 26, 2023, 06:25:32 AM
I thought about buying some of those in line. But I was wondering if there was a cleaner way to do that. The Moreplay is feeding a pair of Heathkit W5M amplifiers for my tube setup and a Hafler DH-200 for my Solid State Setup.

Both are running to some Klipsch Forte IV’s through an A/B switch.

I just flipped the switch and turn on whichever power amplifier I would like to listen to

With the HeathKits, I have full range of the volume control. With the Hafler, my normal, listening volume is just about a 1/8” turn up on the volume Pot.

This certainly isn’t a big deal. But I just thought if there was a clean, easy way to adjust this at the Preamp, I would like to do it.

I’m not sure why it’s not allowing me to upload photos but it’s telling me that they are the wrong format.



Offline Paul Birkeland

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Reply #3 on: January 26, 2023, 08:31:41 AM
The DH-200/Forte combination really should just be avoided.  At minimum -12dB attenuators at the input of the Hafler would be a good idea, but that amp is a better match for speakers that are far less sensitive.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Dzrout

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Reply #4 on: January 26, 2023, 08:56:37 AM
I totally understand. I really just wanted some thing that could provide the louder volume wall shaking bass that I wasn’t getting with my tube amps.

90% of my listening is done through the HeathKits. Occasionally, I would like a lot of volume, but it would be nice to have more control and range 



Offline Paul Birkeland

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Reply #5 on: January 26, 2023, 09:24:19 AM
If you also have both amplifiers cabled to the speakers at the same time, that isn't something I'd be wild about.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Dzrout

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Reply #6 on: January 27, 2023, 03:46:05 AM
They both go to an A/B switch I have the Hafler on one side and the HeathKits on the other, so only the amp I am listening to is actually connected to the speakers.