Kevin

Voltsecond, as you will see, has other Paramour mods and the Bottlehead Forum discuses everything from iron and choke upgrades to simply putting a cap on the mains line switch.

Spend a little money, have a boatload of fun.

I've tried two mods from stock with my 'Mours to drive my Theater 4's. The first was to switch the primary of the output transformer to the .625watt tap from the stock 1.25w tap. This seemed to smooth the high end a bit and add a bit of umph to the bass. The second mod was VoltSecond's Cathode Mod (the other way to parafeed) and this has had more noticable change to the sound. The top end is sweeter and less rough, the midrange is more detailed and the bass is definitely moe extended and punchy with very good detail/texture. Unfortunately, I haven't had much chance to really break in this mod so I somewhat hesitate to gush so loudly, but the distinctly audible nature of the change makes me want to feel that all is good. I'll post more later: probably on the Bottlehead Forum.
Next I plan on adding a second pair of stock output transformers after I let the Cathode Mod break in a bit.

G.

See the thread:

• http://www.audioasylum.com/forums/bottlehead/messages/43021.html

Kevin

Here's a list of my mods in the order installed. Tube rolling is in a separate list below.

1. VS Hum & Noise Reduction V.1 (filament snubber). (I took this out later, since subsequent mods reduced noise to inaudible anyway.)

2. High Voltage Snubber. Reduced noise.

3. Upgraded plate choke to Magnequest BCP-15 and moved old choke over to filter duty. Clarity and solidity greatly improved.

4. C4S board. Essential -- bass is much tighter and cleaner. Plus you get slightly higher gain. This was a huge noise reducer as well.

5. Upgraded power transformer to Magnequest TFA-2004 Nickel. Brought the bass up to solid-state tightness and authority.

6. Installed toggle switches between 4-ohm and 8-ohm taps. I needed this when I was experimenting with different speakers, and have since bypassed them.

7. Removed 12AT7 sockets and rewired driver socket to accept 76s. The result was a softer, warmer sound that I now realize was compensating for harshness in my speakers of the time. Since I got my 4 Pi's, I've switched back to 12AT7s.

8. Cathode parafeed mod. Greater transparency throughout the spectrum.

9. Upgraded coupling cap to Auricap 4uf. Mids and highs are much sweeter and more accurate.

Tube rolling:

2A3: Started with the stock Valve Arts, switched over to Sovteks (didn't like them at all), vintage RCA biplates (wonderful) and finally TJ 300B 2.5V meshies (best of all).

12AT7: My stock tubes were NOS GE's (don't know which year or kind). Switched to Brimar blackplates from Ebay that turned out to be fakes (and didn't sound so great), then GE 6201 5-stars (best high end) and finally Sylvania Gold Pin 6201s (best all around performers).

76: When I had 76s instead of 12AT7s I experimented with a bunch of NOS Sylvanias from different sources. They all sounded identical so far as I could tell.

Hope this helps.
Patrick