A Hot Rodded Bottlehead S.E.X. Amplifier

[HiGHFLYiN9s]

Here's my Bottlehead S.E.X. Kit featuring:

• MagneQuest Transformers
• C4S Upgrade
• Cardas / Kimber / Neotech wiring
• Film power bypass caps
• Cardas RCAs and copper binding posts
• Neutrik locking plug
• Kiwame and Shinkoh resistors in a few places
• Teflon tube sockets and PCBs
• Vintage pilot light
• GoldPoint stepped attenuator

Full build details and more photos are available at: DIY Audio Electronics from Zynsonix.com: The Bottlehead Single Ended Experimenters (S.E.X.) Amplifier

[Cassiel]

Something doesn't make sense, ah, now I see it. 'Premium' parts and those tiny OT's don't match. Also, that is a ridiculous size for a 2.2 uF cap.

Bottlehead's ego is growing like the crocodile in Lacoste clothes. But I like the color.

[HiGHFLYiN9s]

Tea-Bag, the spikes were cheapies from PartsExpress, like 48 cents a pop IIRC.

Black Speaker Spike

[tinitus]

built as 'head' amp ?

[HiGHFLYiN9s]

you bet

[bequerel]

That is soo cool,HiGHFLYiN9s!
Like your emblem.

[kevinkr]

Originally Posted by stalker

Something doesn't make sense, ah, now I see it. 'Premium' parts and those tiny OT's don't match. Also, that is a ridiculous size for a 2.2 uF cap.

Bottlehead's ego is growing like the crocodile in Lacoste clothes. But I like the color.

It's a parafeed amp so don't be misled by the small size of the OPTs - since they don't have to handle DC and are for a very low power amp they can have lots of primary inductance, an exotic core (permalloy, nickel stripe, etc), and since they are small generally have less leakage inductance and stray capacitance meaning their HF response is usually excellent and IMLE well executed can sound pretty good - and this from a fellow who avowedly prefers an OPT carry the full plate current. The Magnequest stuff is very good.

I believe that the OP is entirely responsible for all of the customization here, not Bottlehead, and it's a very nice job.

My only concern is given the tubes used whether or not the point of diminishing returns has been passed and whether or not the money would have been better spent on a 45 based design. No mistake this was obviously a serious effort, and it would be interesting to see how it compares to a more conventional 45 based SE for example. I suspect it is probably the best sounding S.E.X based headphone amp on the East Coast..

[Salas]

I like the colors used and the way it looks like a bomber from the front carrying mean caps underbelly.

[MagnumOpus]

Overkill is underrated

How did you get the emblem done?

[HiGHFLYiN9s]

Originally Posted by kevinkr

I believe that the OP is entirely responsible for all of the customization here, not Bottlehead, and it's a very nice job.

My only concern is given the tubes used whether or not the point of diminishing returns has been passed and whether or not the money would have been better spent on a 45 based design. No mistake this was obviously a serious effort, and it would be interesting to see how it compares to a more conventional 45 based SE for example. I suspect it is probably the best sounding S.E.X based headphone amp on the East Coast..

You're right on Kevin, I did all the extra little upgrades listed above on my own accord. I tend to like putting my own little spin on a kit as part of the creative process. I'd imagine a 45 design would likely sound better, I'll find out when I'm done building the TubeLab SE that's been sitting on the "to-do" list for a number of months. That being said, the nice thing about the S.E.X. design is you can use both headphones and speakers with it. The Tubelab can also do either, but I believe it needs to be configured one way or the other.

Originally Posted by MagnumOpus

Overkill is underrated
How did you get the emblem done?

Heh, indeed. I made the emblem on the computer in Illustrator and sent it over to a guy I know in promotional products. He sent it to a company that makes custom metal badges in a number of colors (gold, silver, bronze, etc.). If I had known what they cost before I ordered them, I wouldn't have :P, but they do look nice at least