Paramounts - first build for someone else

[ToolGuyFred]

Here we have one of the last pair of Paramounts (there were two pairs left when I placed the order). Pictures taken straight after the build so I still need to get a fine brush and black paint to touch up the screw heads.

Chassis plates were sent to the anodisers for black hard anodising. They came back polished and in this grey colour which we decided to keep (something to do with specifying *hard* anodising I suspect).

Wood bases were finished with a rounding off cutter (I like the look and can never get a finish I'm happy with when there are sharp edges). Three coats of black wood stain were topped with three coats of high beeswax content polish.

The new owner is my son. I once lent him my ParaSEX amps while I was on vacation and he was noticeably reluctant to return them. I offered to build him tube amps of his own and asked what he wanted - "Something based on a 300b" came the reply - he'd obviously done some research. Audio Note UK had just discontinued the Kit 1, so I suggested Paramounts. They have been on his shopping list ever since, so when they were being discontinued we went for it.

His is very happy with his first venture into tube amplification.

Just added 16th Jan: Nice blue glow from the 300B and how we squeezed in a Kommie Kap for the HT supply.

 

[mcandmar]

Those turned out lovely, nice work      Love the old IBM keyboard, those things really do last forever.

 

[Adrian]

Looks like an old Omega multimeter there.

 

[ToolGuyFred]

Looks like an old Omega multimeter there.

Its a Kiethley 130A. My first one (1986) was stolen from a company car in the early '90s (along with the rest of the tools I use for work). This one was the replacement from the insurance company.

 

[ToolGuyFred]

Those turned out lovely, nice work      Love the old IBM keyboard, those things really do last forever.

Thanks.

My son & I both write software as a day job (me to control industrial machinery, him for pharmaceutical trials) and we haven't found anything we like better than the old IBM PC keyboards.

 

[Adrian]

Its a Kiethley 130A. My first one (1986) was stolen from a company car in the early '90s (along with the rest of the tools I use for work). This one was the replacement from the insurance company.

John
I jumped on the Omega multimeter because your Kiethley has the exact same casing, coloring, layout and styling as an Omega 871 digital thermometer:

http://www.omega.com/pptst/870_HANDHELD.html

 

[ToolGuyFred]

John
I jumped on the Omega multimeter because your Kiethley has the exact same casing, coloring, layout and styling as an Omega 871 digital thermometer:

http://www.omega.com/pptst/870_HANDHELD.html

Looking at this, I would be very surprised if the cases for Omega  and Keithley weren't made in the same factory.

 

[ToolGuyFred]

Bump - new pictures.

 

[Natural Sound]

Nice pix!

You might want to consider adding some ventilation holes in that bottom cover.

 

[ToolGuyFred]

Nice pix!

You might want to consider adding some ventilation holes in that bottom cover.

Fair point.

I have thought about this but there are no holes in the Paramount chassis plate to let the air through - so hot air being less dense than cool, there will be no air movement to take the heat away. If I  want to add holes to the chassis plates then  I am literally in for a hard time as that anodizing is like glass - I had to grind away some of it for the main grounding point.

 

[Paul Birkeland]

I have thought about this but there are no holes in the Paramount chassis plate to let the air through

If the power transformer is properly mounted, air will flow from inside the chassis up through the hole where the power transformer pokes through, and out under the power transformer.

 

[ToolGuyFred]

The latest Paramounts have the transformer mounted on slim nylon  top-hat spacers which leaves a lot less space for the air to come through than when nuts were used as spacers (contrast the manual front cover with the pictures above) but I will add some holes anyway - these transformers are getting properly hot - see this post. http://bottlehead.com/smf/index.php?topic=8793.0

 

[Deluk]

Anodising does make for a tough surface but it will be no match for a sharp drill. A neat pattern of holes taking up 20-25% of the area plus 3-4 3/4" (say) holes in the back face of the plinth, at the top, should flow a fair amount of air and won't look out of place if done neatly. Bigger holes plus a small grill could also be an option.

 

[Paul Birkeland]

The latest Paramounts have the transformer mounted on slim nylon  top-hat spacers which leaves a lot less space for the air to come through than when nuts were used as spacers

All Paramounts have the nylon spacers and nuts are not used as spacers.  We have seen no heat related issues with the Paramount, but drilling holes in your top plate may have other unintended consequences.

If you want to free up a little air flow without as much effort, a small pair of standoffs can be used between the hole shrinker and chassis on each amplifier, providing some additional space for air to leave the underside of the chassis.