Opinions on vintage cj amps and Teflon cap mods


I'm seeking opinions on having a vintage amp modified/updated. While I'm enjoying my conrad johnson Premier V as is, I can hear some significant differences when compared to some of the more modern amps I've heard. In my opinion, the sound I'm getting from my system is too soft, particularly the leading edge of notes and the upper base/lower mids. Decay, air, ambiance and overall musicality are great IMO. conrad johnson is offering modifications to the Premier 4&5 amplifiers which would include a new power supply and Teflon capacitors. What's crucial to me, is that I'm looking to improve the amplifiers performance, not just change it. The cj person I talked with said they've modified a couple of the Premier 4s with "smashing success". Thanks in advance for your experiences and opinions.
phaelon
If CJ is doing the mods themselves they should be able to give you more specific details on the change in sound you can expect.

Power supply caps are often deteriorated in vintage amps. I've refurbished a pair of Fisher 80AZ's, and a pair of Dynaco Mk III both with new power supply caps, and teflon coupling caps.

I've been very pleased wherever I've been able to afford to use teflon caps. The DO take seriuos amounts of break in time to sound right, and may even sound worse initially.

John C.
I'm planning on capacitor upgrades to my CJ MV-55. I will use Jantzen Z-Superior Copper at the lower end of price scale, VH Audio V-Caps at higher end.

Based on my experience, either of these caps should provide the improvements you're looking for, while retaining the essential CJ sound. I wonder what caps CJ uses in their upgrade?
Hi Phaelon,

A "new" power supply in a 1984 vintage amp would make one heck of a difference, detail would probably improve along with more bass definition and solidity, along with better control over all. The new coupling caps will help too, but you've got a ton of output tubes (8 EL34's) so trying some other tubes might be another avenue, but I would go for the power supply and cap upgrade and see where you stand.

This can't be cheap though, and you really have to like the amps in their present state to spend more $$ on them.

Improved performance is a sticky issue, since the amps performance (output power, bandwith, stability) are a function of the circut to a great extent. The fact that CJ is doing the work is a big plus. Good luck.

Regards..Paul