Bottlehead Forum
Bottlehead Kits => Legacy Kit Products => Reduction => Topic started by: Karl5150 on April 25, 2014, 10:32:10 AM
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Is there any problem daisy-chaining a second set of RCA outs on my Reduction? (besides difficulty drilling holes in the plate)
I know my fine sounding S.E.X. is a great can-amp, but I prefer 1 function machines and apparently like building BH kits.
Thanks
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You will need to check the impedance of the two preamps or amps you will feed. You don't want to drop below the minimum load impedance Bottlehead suggests. The two will be in parallel.
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Thanks Grainger, apparently I was a bit obtuse. I'm gonna build a Crack and each will run directly off the reduction one at a time. The 2nd set of jacks would be so I don't have to swap cables.
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In stock form, both SEX and Crack have 100K input resistance, so both together will give 50K. It makes no difference whether they are on or off. Reduction will drive 50K well.
The cable capacitance is additive, so if Reduction will drive a 2-meter cable then you can use two 1-meter cables. That's probably the biggest limitation. The effect of longer cables is subtle, and low-capacitance cables can be longer than regular ones - listening tests will likely be useful.
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Thank you Paul. Sounds like a switch as used in other preamps would be a better approach.
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I added DPDT on-off-on toggle switches (1 ea ch) and a second set of RCA outs to the Reduction. I wired it with the leftovers from my SEX kit, twisted.
I moved the left C4S ground to the common ground on the left channel toggle, and it all works well. The only other changes were replacing the single 0.01uF cap (19-22L) sourced from BH (thanks your highness) and the 475kOHM 1/8w resistor (22-23L) sourced from Mouser. Although it has the same DALE 4375F designation it is physically larger than the ones originally supplied.
While it makes music with no added noise or hum, I notice a harshness, especially on vocals. It does not seem isolated to the the left channel where the components were replaced. It seemed to lessen slightly with time, but I was also moving from a known harsh recording (reissue of Queen's News of theWorld) to an older pressing of another rock album I am very familliar with. Less harsh but not as easy to listen to as before.
Thoughts?
Thanks,
Karl
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Thoughts?
How many hours are on your Reduction?
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Hundreds since the original build, dozens since solving the integration issue, although I did install new tubes as part of the troubleshoot. Hmmmm. Give it time?