Preamp pcb

[viki_v2]

Hello Friends,
I need help for building a tube preamp ,to be paired with b500 amp.
Request help from all.

Regards

 

[mastodon]

What are your requirements and preferences?

 

[viki_v2]

frankly i do not posses much knowledge about these things, So any help is welcome.
The amp i am building is 500 watts amp.
i have heard solid state things, and now want to feel the musicality of tubes.
some help on what to look for will help me in deciding.

 

[DF96]

Well-designed tube preamps don't have musicality, but are simply transparent.

 

[viki_v2]

I would ike to feel what ransparent is like.
Tubes tend to give smooth and warm sound isnt it.

 

[Andy5112405]

Have a look at my Borbelly tube line-amp on the Pass forum. Search for Suggest me a pre-amp for my F4.

 

[pinkmouse]

SY's Red Light District. Best pre I've ever built.

 

[Dragondreams]

Over the weekend, I built a VERY simple pre-amp using a minimal number of components. To my ears, it's very transparent. At the moment I'm feeding it into a cheap Samson reference amplifier powering a pair of MS 816 speakers and it knocks spots off the old Technics hi fi amp that used to sit in my living room.

Most of the components can be soldered direct to the valve bases, and I used a piece of Veroboard for the power supply.
E80F/EF86 pre-amp

 

[kstagger]

I'll second the triode connected EF86 preamp - I used a white cathode follower on the end of mine. Very nice sounding with budget or tricky-dicky parts.

 

[Andy5112405]

An externally hosted image should be here but it was not working when we last tested it.

The Borbelly was easy to clone and uses readilly available ECC83 and ECC81 valves

An externally hosted image should be here but it was not working when we last tested it.

 

[Dragondreams]

An externally hosted image should be here but it was not working when we last tested it.

The Borbelly was easy to clone and uses readilly available ECC83 and ECC81 valves

An externally hosted image should be here but it was not working when we last tested it.

Andy, the links don't seem to be working (and I'm interested in this one myself). 😉

 

[Andy5112405]

ImageShack® - Online Photo and Video Hosting
ImageShack® - Online Photo and Video Hosting

Let's see if it works this time.

 

[Andy5112405]

http://img137.imageshack.us/i/pcb007.jpg/
And the PSU

 

[SY]

SY's Red Light District. Best pre I've ever built.

I think you mean the Heretical. 😀 I'm currently running a six channel version using the boards left over from the run you did.

 

[Dragondreams]

Thanks Andy 🙂

I've just been reading through your posts in the Pass Labs forum about this pre-amp. Nice work.

Just hunting through my parts bin now! 😉

 

[Andy5112405]

The problem I had was the HT supply. It's unusual, that's why I used 5 x 22V transformers. 9 x secondaries gave me the 198V AC that I needed. The 6VA transformers were tiny and very cheap from RS.

 

[Dragondreams]

The 6VA transformers were tiny and very cheap from RS.

😀

I've just this second added them to my RS shopping basket!

Many thanks for the information.

 

[Andy5112405]

If you buy the RS (Indian) transformers, be prepared to experiment with the secondary phasing. I thought 0-22 + 0-22 meant what it said but I had to swap a few wires around to get true 0-22 + 0-22. With no load attached you will not do any harm. It's a simple case of testing the windings to make sure that they are adding together and not anti-phase.

My first attempt gave me 15V DC - great for 9 x 22 V

 

[pinkmouse]

I think you mean the Heretical. 😀 I'm currently running a six channel version using the boards left over from the run you did.

Whatever... 🙂

Six way pot, or digital?

 

[SY]

Six way pot. A nice Alps unit, motor driven, which will someday be remorely controllable.