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Balanced tube preamp

mr.me

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Any recommendations for a fully balanced tube preamp. Not got lots of dosh to throw at one so will be looking at used.

 

JANDL100

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Jerry
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^ 6n11 output valves - Chinese type with no equivalents as far as I can see. 

I like to roll, so I'd probably look elsewhere. 

Must admit, I'm in the market for a valve preamp as well, but not balanced and with remote control! 

 

Jazid

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Bit tough on Psilonaught's pre there Jerry, it looks to me as though it has 3 x single ended inputs and a pair of single endd otputs as well, takes E88CC and similar (and 7SN7 with an adapter)so is easy to roll with, and has remote control as well! It has a few excellent reviews which may or may not be stooges I suppose, and overall looks quite a tidy bit of kit at that price. What I can't tell from the pics is whether the circuit is true balanced or not, I suspect not since that would save an enormous amount of aggro for the designer and builder especially with valve matching.

The only balanced pre's I know are all rather expensive. I would love a Vacuum State RTP3 but they are rare as hen's teeth on the used marlet and not cheap.

 

rabski

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I'm having a grumpy moment, so...

It's not balanced. The details state "MP-701 MK2 is based on single ended circuit. XLR is converted from RCA for convenience, so user can use existing XLR cables". In other words, it's single-ended with XLR sockets glued on.

WRT the tube rolling, anything that can use 6N11, 6N1P, E88CC, E188CC, 6922, 6H23, 6H6, 6H30, 6SN7, 12AU7, 12BH7, E80CC, and 12SN7 will sound different between the different valves for sure. Not by virtue of 'rolling', but because most of them will be running way outside their optimal point. A proper circuit is designed for one type of valve, or (very) near equivalents.

It's a valve effects box.

 

Jazid

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Damn, should've read the blurb. OK, bit of a waste of balanced connectors then. Special effects box sounds good though? [emoji13]

Sent from my BLA-L09 using Tapatalk

 
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Psilonaught

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It's not balanced. The details state "MP-701 MK2 is based on single ended circuit. XLR is converted from RCA for convenience, so user can use existing XLR cables". In other words, it's single-ended with XLR sockets glued on.
Fair enough that doesn't sound good 

 

mr.me

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I have a pair of Monarchy Audio SM70 Pro amps winging their way to me and I would like to connect them in the configuration below. My tube pre does not have XLR balanced outputs and according to the blurb on the amps this is the best way to connect them.

Must admit, I'm in the market for a valve preamp as well, but not balanced and with remote control! 
Jerry, If I can find a balanced pre I have a "nearly new" PrimaLuna Prologue Premium with remote with barely 10 hours on it should you be interested

SM70PRO_Balanced_connect.jpg


 

mr.me

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Has anyone used or know anything about this S/E to balanced XLR converter as per link in previous post.

s-l1600.jpg


 

Disarmamant

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Has anyone used or know anything about this S/E to balanced XLR converter as per link in previous post.
Uses NE5532 op amps to facilitate unbalanced input to balanced output and vice versa.

No information on the gain available, but as it’s op amp based it would be fairly easy to adjust the gain.