New tube preamp arrives this week

My first new preamp in a decade arrived this week. Designed and crafted by Emmanuel Go: the First Sound Presence Deluxe 4.0 MkIII-Si Special Edition with ugraded AudioCap copper capacitors. This preamp has a lot of unique features...


The First Sound preamps are essentially "bespoke" preamps, each one crafted and tuned specifically for the owner's system and system components. The design is a true dual-mono design, two preamps in one main control chassis with the PS transformer and PS capacitors housed in two external chassis, one per channel, to maximize performance while minimizing the impact of noise and vibration on the main circuit. Additionally, the main control unit is two mono chassis in one, with an inner chassis comprised of copper-plated steel to function as a Faraday cage to further reduce the impact of external noise.

Special care is also provided to provide vibration-damping and even the fasteners were selected based on comprehensive, long-term, listening tests.

Notable are hand-assembled volume controls, utilizing individual exceptionally high-quality metal film resistors at each gain position and a massive power supply, exceeding the power supply capacitance and "stiffness" of many high-end power amplifiers. Each channel has 145,200 uF of capacitance for a total of 290,400 uF.

Dual Mono Construction using Copper Plated Steel Chassis
• Step Attenuators, Ladder Type using individual resistors (see below), designated as LTH 92
• SPS 2.0 External Power Supply w/ detachable umbilical cord
MkIII-S upgrade
• MPDA (multi-phase differential array) developed by Shunyata Research. A sophisticated and innovative proprietary power line noise reduction filter array. Uses advanced 30 element surface mount components that significantly reduce power line noise.
• PSDS (power supply delivery system) An advanced system utilized for the power supplies..
• Upgraded main circuit boards
• Upgraded power supply circuits boards
• Additional 500 extra steps in the craftsmanship of this upgrade
MKIII-SI Upgrade
• As above with the addition of proprietary component filters that isolate electrical noise.
Paramount Special Edition upgrade
As the Presence Deluxe MKIII-SI with the addition of:
• LTV 92 Step Attenuators, Ladder Type attenuators using naked Holco Resistors
• Upgraded (Stage 3) Capacitors using AudioCap copper capacitors
• Expanded power supply capacitors
• Special Edition grounding topology

Volume attenuator


Interior copper chassis


Some first pics....

Control unit front panel...definitely an MBL vibe...


The two massive exterior power supplies, one for each channel; these connect to the main control unit with umbilicals by Shunyata.



Top view without the covers; there are only two tubes, a 6DJ8 and OA tube per channel. The preamp is a true dual-mono design; two mono preamps mounted in a single chassis.Each channel has 145,200 uF of capacitance for a total of 290,400 uF.



Just some, but not all of the power supply capacitance...and yes, that blue and brown wire is Shunyata Research OFE wire connecting everything. Emmanuel Go and Caelin collaborated on incorporating several Shunyata technologies into First Sound preamps. The 6DJ8 triodes can also be seen in this photo. These tubes are super-durable, with mean life over 100,000 hours.



The back panel shows input jacks, wiring and huge copper bus bars for making and grounding connections. Note that there is no ground wire for each RCA jack, only a single + connection. There is also no insulation on the wires so as to not have any dielectric effect from various insulation materials; the dielectric in this case is air. The entire copper bus bar serves a ground for all inputs. There is also a switch (little red box) for each channel that lets me float the ground in the advent of any ground hum (there isn't; this preamp is DEAD QUIET).


A close-up of the volume attenuator with individual metal film resistors.


There are also large, heavy, copper bus bars for chassis-grounding.


AudioCap copper capacitors.



A view of the front panel and part of the chassis interior...



The interior of one of the two external power supplies, showing filter caps, transformer and Shunyata Research MDPA noise filters.



I've been listening to it for about 4 hours each evening as it burns in, and its already pretty fabulous.

 

OK, sure, that'd be ok for casual listening, but some of us actually care about sound quality...

J/k, that thing looks amazing!

I've done some rolling of 6DJ8s, are you planning on trying some vintage glass or staying with the stock tubes?

 

personally I won't buy any preamp unless there is at least 300,000 uF capacitance per channel

 

so this is an ORFAS pre-amp with a list price of $5.4k US, not including the bling bling options I assume?

for $5.4k, why do we get a wimpy 6922 and not a full-fledged DHT line section?
for $5.4k, why do we get a stepped resistor attenuator and not autoformers?
btw, I will never understand the audiophile obsession to avoid carbon potentiometers at all costs. I would much rather listen to a humble ALPS pot than boutique metal film resistors and their nasty overtones
for $5.4k, why are the power supplies rectified by silicon diodes instead of tubes?
for $5.4k, why do we get input and output coupling via overpriced film capacitors instead of line transformers?
why do you need 3 zillion uF filtering capacitance to power a single 6922?

lastly, no traditional triode has a mean life span of 100,000 hours. even nuvistors cap out at around 50,000. the life span of a 6DJ8 is more like ~8000 hours

I am very confused! it seems all your money went into the chassis and not the circuit!

 

Cheap for an ORFAS preamp, actually. If I needed one, this is the sort of thing I'd personally be looking for.

I agree with you here, although I don't feel the way you do about the other design decisions you mentioned.

Untrue. The original 6922s in my power amp were powered 24 hours a day, 51 weeks a year, for 15 years. That's 125,000 hours, and when I finally replaced them a couple months ago, one had just barely started to hiss.

 

6DJ8s are some pretty sweet tubes, or at least some versions are. ORFAS or no, this could be a pretty sweet sounding preamp.

 

It is...it's the best-sounding preamp I've ever heard, and I've heard some very good preamps including C-J, ARC, Shindo Giscours, TAD, Esoteric, etc.

 

I'm using the tubes that Emmanuel provided, he did extensive testing on which ones sounded best and also provided excellent durability.

 

@Puma Cat Do you get used to adjusting the volume individually per channel? I wonder if a remote control function could be added with a stepper motor driving cog belts to a pulley on both volume rods inside the chassis. Seems like the center of the chassis is full, so you might need two stepper motors, but there should be plenty of room on each side.

 

Hi Francis,

It's not a problem...I just walk all of 7 or 8 feet over the pre, and adjust the volume knobs to the same detent for each channel. Takes all of a few seconds; less time than flipping over and cueing up an LP, actually.

And, I'm not going to mess with Emmanuel's design or second-guess his design approach; his designs are "no-compromise".

Which is why this preamp sounds as amazing as it does.