Hot-Rodded Seduction

[HF9]

After becoming addicted to my Crack, I had to get my next fix from the Seduction build. Here's some photos to enjoy

It features the following upgrades:
C4S Upgrade Board
Gold Obbligato Caps (0.47uf and 0.1uf)
Cardas Rhodium input and output RCAs
Slightly nicer than stock Pany and Nichicon caps in the power supply
Cardas, Kimber and Neotech Teflon wiring.
Teflon Noval Sockets and PCBs
Takman Carbon Film Resistors

 

[JC]

Really gorgeous!  How does it sound?

 

[mrarroyo]

Nicely done Bryan! Enjoy it.

 

[HF9]

Thanks very much gents Now that the caps have had a little bit of time to form, everything is sounding really excellent. I could probably stand for a tiny bit more gain for my Denon DL-160 but overall I've very pleased with the sound.

Considering future upgrades... I may try adding some teflon bypass caps to the output to try and eek out a tiny bit more detail.

 

[Mikey]

Those PCB tube sockets are kinda cool....where did you get them?

Mike

 

[Grainger49]

Nice work!  I always like the finish on a base giving some character and grain to it.

I think my first Seduction mod was a 0.1uF@200V KK Teflon between the stages.  I liked it immediately.  Since then I bypassed my output caps with them too.  (and of course all kinds of caps changed everywhere)

 

[HF9]

The PCB tube sockets are from good old Partsconnexion, they're made to go with the teflon sockets to ease the soldering process. The small pins are soldered to the PCB and then you have some spaced out through-holes to work with.

I'm going to pick up some of the smallish Russian (KKs as you call them ) teflon caps for bypassing purposes. 4700pf should be adequate for the output caps. The teflon caps are so huge. I purchased some 0.22uf a while back for another project and they were like 4 or 5 inches long

 

[Grainger49]

Have you seen the 0.47uF@200V???  They are Ginormous!  I posted a picture somewhere.  Reply 8 on this page:

http://www.bottlehead.com/smf/index.php/topic,33.0.html

That is a 3A 12.6V transformer in the background.

 

[HF9]

Caps the size of beercans, eh?

 

[Grainger49]

I think they would make a 2 oz jigger rather than beer cans.  My oilers in my FP 2 power supply are beer cans.

 

[HF9]

Added a Pilot Light and Teflon Bypass caps:

 

[Grainger49]

Nice and very neat work!  Cute little Teflons, what value.

 

[HF9]

Thanks Grainger, they are 2200pF.

 

[Grainger49]

I had wondered how they could be so small.

 

[HF9]

In the interest of a little tweak for the Seduction, a pair of Hammond 155J chokes were added to the power supply in place of the two 1K resistors. On paper, they are 1026 ohms +/- 15%. In practice, they measured about 900 ohms each, which should be close enough for this purpose. Chokes allows better filtering in the power supply (less hum in the output of the amp and less voltage drop) which should translate to better sound. There's a nice quick lesson on the purpose of chokes here: http://www.aikenamps.com/Chokes.html . Since the stock Bottlehead design lifts the transformer with a pair of standoffs for noise reduction, I decided to use a pair of standoffs for the chokes to physically move them away from the tubes. As typical with Bottlehead kits, once you start dropping in some fancy parts, the real estate tends to go pretty quickly. The most accommodating place to mount them in my case was right next to the C4S constant current upgrade board.

The upgrade required about a half hour of time to mount the chokes and solder them in place, along with about $30 plus shipping for the chokes themselves.

 

[Dobs]

And the sound with choke installed?

 

[HF9]

Warm and smooth, no notable noise in the PS.

 

[Dobs]

Im sorry, i would have formulated my question as: Can you hear a difference with choke installed.