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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
phaelon OP
1,049 posts
 
Hi Casouza, Your post helps tremendously. You addressed all of the issues in question. Ultimately, I have to make a decision and it would seem to come down to this: 1) Would I be better off trying to restore these amps to as close to original spec as possible, 2)sell them, combining the revenue with the cost of the upgrade and buy a different amp or 3)taking a chance on the upgrade and hope that lightening strikes. Regardless of which I choose, your post is most appreciated. They all are.
casouza
239 posts
 
Hi Phaelon, thanks for your kind words.
I really can not answer your doubts, having no experience with your particular model CJ amp, however, if you like and enjoy your system as it is today, the upgrade will certainly be an incremental improvement across-the-board, because power supplies and coupling caps DO matter. Capacitor technology has evolved a lot in the past 10 years.
Reminder: give teflon caps 200-300 hours of play to sound their best. Initially, things may sound a bit weird.

If you are not happy with your system, then by all means "open the can of worms" AKA amplifier/speaker sinergy.

In the past five years, I went though several amplifiers: 50W SS, 200W SS, 400W SS, 500W SS (notice the power-race trend?), then 90 W McIntosh tube amp ...to end up with a measly 20 Watts Hyperion SET tube amp...now I am as happy as a kid in a candy store.

Sns, CJ capacitors are custom-made by CEC in the USA.
downunder
1,329 posts
 
I recently bought a pair of cj prem 8a's and had conrad johnson do the teflon cap upgrade.

The upgrade consisted of replacing the eight coupling capacitors (inverter to output tubes) with .15 uF Teflon capacitors and replacing 6 more capacitors (four in the regulated supplies, two in the unregulated main supply) with .15 uF Teflon. Filament diodes were replaced with "beefier" diodes

No downside whatsoever. Maintains the strengths of original prem 8a while adding transparancy, seperation and overall ease of delivery.

Highly recommended for any owner of older cj amplifiers.
downunder
1,329 posts
 
Interesting that cj now have the upgrade detail on their web site
http://www.conradjohnson.com/It_just_sounds_right/cap_upgrades.html

Luving the premier 8a's with the teflon cap upgrade now that I have over 400 hours on them

cheers
sherod
1,690 posts
 
Does CJ offer these proprietary caps separately as parts for DIY in other makes or is this strictly for their own use in CJ model upgrades?
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