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Need input on Buffer stage to use in Preamp..

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A

Adrculda

Member
Joined 2009
Hey guys...
I'm well under way on a amp build im working on currently and would like to slowly start gathering parts for the matching preamp.
starting with the output, i would like to have a selectable output configuration and want to incorporate a tube buffer or preamp stage on one output and a HDAM preamp on the other.

Theres a lot of EBAY kits and im not to tube "savy" so i figgure before i start burning money is always worth asking which one is worth it and what to look for :)


The reason why i want to incorporate a tube section is because i had to replace a board and a few items on a friends Dynaco PAS2 and after had it for a "burn in" for 2 weeks it sounded amazing to me, hence why i want to add one to my build :)

ALSO, balanced signal handling would be a BONUS !!!

Input needed on this kit to start off with...
 
Zen Mod

Zen Mod

Official Court Jester
Joined 2003
zenmod.in.rs/
Paid Member
drek - short and simple

if you need tube buffer - SLCF , Allen Wright , google

edit : for 143$ ........ better use much smaller money , and buy tube preamp cookbook and supercable cookbook from mentioned tube wakoo ...... that way you'll learn something ..... and never ever think again about buying audiophool fog on ebay
 
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Arnulf

Member
Joined 2009
Well, you could ... I just wonder why you'd need this horribly inefficient use of ECC83s doing double duty WITH 2000+x GAIN functioning as a buffer. Do you plan to put an attenuator somewhere that will quiet this thing down two thousand plus times ?

Oh and ECC83 doesn't make the best cathode follower out there, no matter what the schematic in your link says.
 
A

Adrculda

Member
Joined 2009
Basicly what I'm doing is building a Pre-amp to my own needs and wants....

Will include basic functions as Volume and Source Select - 4 XLR pairs, 2 TRS Pairs and 5 RCA Pairs with a "Monitor" Function. This will allow the use of a external processor or DSP and will have 1 pair of XLR's and TRS's . All unbalanced signals will be up-converted to Balanced Signal and handled internally in the balanced form. Output will be Balanced ( XLR and TRS ) and will also include a summing amp to have a pair of RCA's.

The Output Section will be selectable as either tube to HDAM modules with JFET's
Still debating if i want to incorporate a DSP board for time correction with a Graphic or Parametric EQ, but will have a Bypass for "source direct" mode.

For the Tube Section I'm looking to find a PCB that i can populate on my own and dont have to go through the trouble of trying to do a complete layout.


The whole idea of this preamp is to have a clean, accurate and detailed sound with best of both "worlds" tube and analog.
Maybe eventually will add a digital output section as well... maybe...
 
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Adrculda

Member
Joined 2009
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DougL

Member
Joined 2004
If your requirement is a PC board, I have a couple of recommendations.
For a buffer:
Aikido Cathode Follower PCB

And for a HDMA:
CCDA 9-Pin PCB & Kits or
Aikido 9-Pin All in One Kit

And if you need a power supply:
PS-3

These are original designs, using current design ideas.
They are inexpensive, and well documented.

I was going to comment on your previous choices, but I could not find anything suitable to say. Lets just say I strongly disapprove of knockoffs, especially "enhanced" knockoffs.

For what its worth.

Doug
 
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DF96

R.I.P.
Joined 2007
myweb.tiscali.co.uk/g8hqp/
Looking at your list of requirements, if it was fruit you were after it would be something which tastes like apple and orange but looks like a banana!

You seem to want tube sound, SS sound, accuracy and sound processing all in the same preamp. Oh, and both balanced and unbalanced. Then you ask us to choose it for you.

Would you buy a car in this way? Send a friend to choose it, with instructions "I want a small safe family runabout, with turbocharged 4 litre engine, top speed 150mph. Must look sporty, but plenty of room for a major shopping trip. I can't decide whether I want left-hand or right-hand drive."
 
A

Adrculda

Member
Joined 2009
DF96 said:
Looking at your list of requirements, if it was fruit you were after it would be something which tastes like apple and orange but looks like a banana!

You seem to want tube sound, SS sound, accuracy and sound processing all in the same preamp. Oh, and both balanced and unbalanced. Then you ask us to choose it for you.
Click to expand...

I only need the tube section chosen as i don't have a lot of experience in tubes. The other stuff is simple to implement.

Would you buy a car in this way? Send a friend to choose it, with instructions "I want a small safe family runabout, with turbocharged 4 litre engine, top speed 150mph. Must look sporty, but plenty of room for a major shopping trip. I can't decide whether I want left-hand or right-hand drive."
Click to expand...

That actually a simple answer...
Porsche Panamera Turbo or Audi RS4
 
SY

SY

Ex-Moderator
Joined 2002
SYclotron.com
No schematic and it's being sold on the backs of someone else's trademarks. Poor knockoff of (maybe, who knows?) an obsolete and never that great design. Run away.

John Broskie Aikido. Allen Wright FVP. One of my designs at Tech DIY Company Store (disclaimer: I gave the design away and don't make any money from boards or kits). Lots of good boards out there from honest designers. Why support ripoff artists?
 
kstagger

kstagger

Member
Joined 2003
6streetbridge.blogspot.com/
hard-wiring a linestage/buffer is one of the easiest things in the world to do. Heck, my very first linestage I ever built was a pair of vintage 71A globe tubes with dual power supplies and a whole bunch of milspec parts I bought from Fair Radio. I just used a Hammond Bud box, drilled holes with a step bit and painted the end results.

Just pick a well known schematic and jump on in.
 
A

Adrculda

Member
Joined 2009
Thanks for the input guys :)
As i said earlier, i need a board as it will be housed in a large enclosure with a DAC, a stepped attenuator and source select with a JFET buffer and Tube buffer. Hence why i would prefer a PCB.

Basicly what im trying to accomplish here is a "selectable" output where i can choose between the tube output or the JFET output stage.
 
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