advertisement


[FS] Leak Varislope 3 preamp recreated with low gain 6AH4 valves

les24preludes

les24preludes

pfm Member
For sale here a unique version of the Leak Varislope 3 preamp/line stage, recreated inside with a pair of 6AH4 low gain triodes. 6AH4 is a brilliant sounding valve and one of the favourite preamp valves of high end amp builder Thomas Mayer, as you see here:

vinylsavor.blogspot.com

Tube of the Month: The 6AH4

Hi! Last month we had the 10Y, a directly heated triode which I mostly use as line stage or driver tube. In those applications it requires...
vinylsavor.blogspot.com vinylsavor.blogspot.com

vinylsavor.blogspot.com

The 6AH4 Line Stage

Hi! Since I mostly write about the 10Y linestages (those are also requested more often) many are not aware that I also offer a smaller, s...
vinylsavor.blogspot.com vinylsavor.blogspot.com

Photos here:

Low Rp tube for line stage - ideas?

What's the output impedance using CCS for 12B4 Here Ya Are. Simulation shows -3 db is at ~180 KHz for 12B4 CC Loading When R = Xc, if we know f we can solve for R f = 1 / 2*PI*RC……………………….f ~ 0.16 / RC F ~ 180 KHz and C is 200 pF R ~ 0.15 / fC………………R ~ 0.16 * ( 0.2*10^9 ) / (0.18*10^6) R...
www.diyaudio.com www.diyaudio.com

This recreation keeps the lovely retro facade of the original Leak, and has been rebuilt with the finest audiophile parts
- Teflon coupling caps
- Elna Silmic 2 cathode bypasses (upgradable to Audio Note Kaisei)
- Shunt volume control with NOS carbon resistors
- Wirewound anode resistors
- Two 6AH4 with gain of around x7, 1.8K output impedance
- Power Supply with 9H, 40mA choke, Schottky 1200V diodes and input mains filter.

Not surprisingly this is a huge upgrade on the original and equivalent to typical audiophile high end line stages in sound quality.

3 switchable RCA inputs and one pair of outputs.

£360 + shipping, or collect from Kensington, London.

Full set of photos available by PM. Andy
 
Last edited:
eastone said:
I bet this sounds lovely.
Click to expand...

It really does! The 6AH4 is one of my top favourite valves, same with Thomas Mayer who used it in some very high end line stages.

Pretty unique to have this circuit in a Varislope preamp. I built it out of nostalgia - we had this exact preamp in our Leak system driving a Stereo 20 when I was growing up. Happy memories!

Andy
 
I have now upgraded the cathode bypass caps to Audio Note Kaisei 100uF in parallel with Elna Silmic II 100uF. This was the best sounding bypass cap I found in a whole day of A-B testing of around 8 different ones from HiFi Collective.

The price is still £340. Photos on this link. This is a really good sounding line stage. Andy

Low Rp tube for line stage - ideas?

What's the output impedance using CCS for 12B4 Here Ya Are. Simulation shows -3 db is at ~180 KHz for 12B4 CC Loading When R = Xc, if we know f we can solve for R f = 1 / 2*PI*RC……………………….f ~ 0.16 / RC F ~ 180 KHz and C is 200 pF R ~ 0.15 / fC………………R ~ 0.16 * ( 0.2*10^9 ) / (0.18*10^6) R...
www.diyaudio.com www.diyaudio.com
 
eastone said:
Just seen the pics, looks great and worth pointing out that the PS is external (a plus I think?). Are the tone controls intact?
Click to expand...

Thanks for the thumbs up. The selector switch on the left selects between the 3 inputs and the volume control is the knob in the centre. The rest is non operational.

The on-off switch is on the external power supply,
 
You must log in or register to reply here.


advertisement


Back
Top