Hi,
I'm currently running a preamp that is driving 3 amps. One pair of tube monoblock amps, a 2 channel tube amp and then a plate amp that drives a subwoofer.
If I'm running the tube monoblock amps and connect the plate amp or the 2 channel tube amp I can hear a little volume drop off in the tube monoblock amps output.... I'm guessing it is just the product of the 3 amps all pulling from the same input signal....
I'm thinking of building some buffers... I was thinking it would be great to have three 2 channel buffers to isolate the signal output of the preamp to the 3 amps. I'd build 2 channel buffers just to have them be more flexable for some other use later.
I'd build them 1 at a time. for a preamp driving 3 amps with the impedance below... between a preamp and the 3 amps below... Where would the 1 buffer do the most good?
I also am finding a lot of good buffer DIY designs on this site. whats best for the buck?
My amps-
--Stereo Tube Amp - Input Impedance 270,000 ohms Input Impedance
--1 Pair 75 Watt Monoblock Tube Amps - 20,000 ohms Input Impedance
--Plate Subwoofer Amp – 22,000 ohms Input Impedance
[/U]
I'm currently running a preamp that is driving 3 amps. One pair of tube monoblock amps, a 2 channel tube amp and then a plate amp that drives a subwoofer.
If I'm running the tube monoblock amps and connect the plate amp or the 2 channel tube amp I can hear a little volume drop off in the tube monoblock amps output.... I'm guessing it is just the product of the 3 amps all pulling from the same input signal....
I'm thinking of building some buffers... I was thinking it would be great to have three 2 channel buffers to isolate the signal output of the preamp to the 3 amps. I'd build 2 channel buffers just to have them be more flexable for some other use later.
I'd build them 1 at a time. for a preamp driving 3 amps with the impedance below... between a preamp and the 3 amps below... Where would the 1 buffer do the most good?
I also am finding a lot of good buffer DIY designs on this site. whats best for the buck?
My amps-
--Stereo Tube Amp - Input Impedance 270,000 ohms Input Impedance
--1 Pair 75 Watt Monoblock Tube Amps - 20,000 ohms Input Impedance
--Plate Subwoofer Amp – 22,000 ohms Input Impedance
[/U]
I recently finished a 6-channel Nelson Pass B1 buffer preamp and it works brilliantly. Very simple circuit and you can share one PSU over all 6 buffers without any issues.
http://www.diyaudio.com/forums/pass-labs/124889-b1-buffer-preamp-319.html#post2805571
http://www.diyaudio.com/forums/pass-labs/124889-b1-buffer-preamp-319.html#post2805571
A bit thanks for the B1 Buffer idea.. Perhaps build that type of design into my output stage of the preamp. I was looking at the B1 builds in the Pass Labs page just a moment ago.
Looks like a lot of capacatance on the power supply. What did you use for a power transformer?
Looks like a lot of capacatance on the power supply. What did you use for a power transformer?
Most circuits i see only use low impedance for the input, where an attenuator is wanted. Majority of interstage circuits i have seen use 100k and 470k values.
I myself use 100k for the grid leak on fixed bias and 470k~1 meg for cathode bias
Im curious whats your up to with your setup, you got quite a variety there:
2 monoblocks, 1 stereo amp and a plate amp. i understand the stereo and the plate, or the two mono's and the plate, but what is up with having all of them?
I myself use 100k for the grid leak on fixed bias and 470k~1 meg for cathode bias
Im curious whats your up to with your setup, you got quite a variety there:
2 monoblocks, 1 stereo amp and a plate amp. i understand the stereo and the plate, or the two mono's and the plate, but what is up with having all of them?
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Maybe he is doing something like: tube stereo for tweeters, tube mono blocks for mids and a ss plate amp for a sub? That is not an uncommon setup.
If that is the case, an active crossover will include the buffers and has the benefit of the amps not wasting power on frequencies not needed. I have used these very successfully:
Linkwitz-Riley Electronic Crossover
If that is the case, an active crossover will include the buffers and has the benefit of the amps not wasting power on frequencies not needed. I have used these very successfully:
Linkwitz-Riley Electronic Crossover
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