No, thank you for sharing!

I would think vibration would not be good for tubes.

BTW, the magazine has a write up by Art Dudley.

http://www.stereophile.com/integratedamps/205prima/

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Here's where your music goes: Each channel's preamp tube is a 12AX7A dual triode, the two halves of which are tied together in parallel in the interest of current gain. From there it goes to the two halves of a 12AU7 driver, configured as a long-tailed pair. Then it's on to a push-pull pair of EL34s operating in "enhanced" class-A/B, with screen grids tied to the output transformer's primary so the tubes can deliver more power than if they were used in triode mode

cannot comment on those particular el-34s, but iv enever owned an amp that did not benefit from the swapping of the "stock" tubes with more desireable ones.

My personal favorite is the

(SED IS Svetlana in Europe. In the US, the New Sensor Corp. Bought the Svetlana name)so..the REAL Svetlanas are sold under the SED "winged C" brand.

Vibration isolation feet and platforms are a good idea. Tube Damping Rings are also quite popular(any number of companies make them, I have These

on my Mastersound Due Venti and Modified Jolida 102b.

Yes, change the tubes. You can find any number of tubes that will surpass the stock tubes. Most O.E.M. tubes are chosen for reliability and the subsequent ability of the manufacturer to have large supply stocks to replace incoming repairs with identical tubes. Under those considerations sound quality is lower on the list for the manufacturer than what you can find in the aftermarket.

Read the sites of a few tube retailers and make a few calls. The Svetlana's overall are a very good tube line for the money spent - you can do better for more money but you could do much worse for the same amount. Remember reading about the "sound" of a tube is only providing a general guide to the basic characteristics of one tube vs another tube. The tube essentially sounds like the circuit in which it is used - so no tube retailer will ever tell you you will definitely acheive "this sound" with "that tube". Your amplifier has been around long enough, however, and had sufficient success in the market that retailers should have a good idea how various tubes work in that circuit. I believe Upscale Audio is the distributor for PL and also sells tubes.

Definitely get the amp off the cabinet. Trying to stop the pas through of vibration strong enough for you to feel by using soft feet and other devices is like throwing rice at a charging rhino. Place the amp on a good surface, just the floor if need be, and listen for the improvement. Proceed from there.

Power cords are a "suck it and see what comes out" proposition. Most anyone who has tried aftermarket power cords will tell you they improve the sound quality to some degree. Whether thay make a difference commensurate with their cost to your budget is a decision only you can decide. Most people who tell you buying power cords just proves you are a f'ing fool susceptible to a charlatan's marketing have never tried a power cord swap. Like tubes, cables and cords are affected by what they connect to.

If you haven't tried any sort of AC treatment devices, I would suggest you audition the PS Audio Duet. A relatively inexpensive power conditioner/surge protector the Duet has never failed to make an improvement in the numerous systems where I have used it.

Tube damping rings can also be a yes/no proposition. They can be too effective at their job and smother the sound. Or they can give the final tweak needed. They are never a substitute for actually setting the amp up with some consideration to vibration/resonances that affect any tube's microphonic nature. Go to your local automotive supply house and ask for some (Neoprene) hi-temp O-rings to fit your small signal tubes. Do not place any sort of rubber/nylon damper on large power tubes, they run much hotter and will generally melt any device you try. Take a sample tube with you (a 12AX7 or whatever is in the front end of that amp) to try for size. The O-rings should cost a few $ apiece rather than the audio reatilers higher price. If the O-rings are successful, decide where you'll then get the most benefit with your next chunk of available cash.

King - Go to the top of the page and click on "My Home", check your PM's.

If you go to the MusicDirect website, they have hundreds of different sonic damper products to choose from.

Personally, for small speakers like your situation, I just go to the store and buy the semi-spherical stick-on rubbery plastic feet that come 4 or 8 in a package, and stick 4 of them on the bottom of the speaker. That usually seems to work well.

a lot of folks use blu-tack for this purpose also.

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If you go to the MusicDirect website, they have hundreds of different sonic damper products to choose from.

Personally, for small speakers like your situation, I just go to the store and buy the semi-spherical stick-on rubbery plastic feet that come 4 or 8 in a package, and stick 4 of them on the bottom of the speaker. That usually seems to work well.

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Tube damping rings can also be a yes/no proposition.

Jan, there is nothing desireable about a tube recieving vibrations or being microphonic. vibration control products/acoustic treatment are areas that , without question, provide clear advantages. cooling/controlling microphonic vibrations--- nothing bad about that at all, there couldnt be.

typical wisdom is that yes, the interconnects are more important than the power cords(many people, myself included) do not feel that power cords make a difference at all, as they cannot possibly negate the effects of the in-wall wiring, home outlets, etc etc.. get a really well built one like
http://www.angelfire.com/biz/bizzyb/ILJPOWER.html

and be done with it.

interconnects are another "black art fringe" proposal, but what I do is get the best I can afford(within reason!) in the thought that IF they do make a difference(I havent heard them make any difference yet), ive gained something..

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Thanks for all the great advice! I will definitely look to replace the stock tubes in the weeks (maybe months) ahead. I must say I like the fact that with a tube amp you can switch out tubes and get a different sound - should ward off the upgrade-itis bug (which usually results in the same thing anyway, just a different sound, not necessarily better sound!)

In terms of moving the amp off of the cabinet, this isn't really feasible as the cabinet runs across the entire wall, and there are sofas on both sides of the walls that connect to it. What I may do to address the vibration issue is build a hardwood platform for the amp to sit on, and place some sort of vibration reducer cones/pads under the platform and the amp itself.

I will also add vibration reducers to the bottom of the speakers, and may even build matching platforms (or perhaps use granite and blue tack the speakers to them) with vibration cones/pads as well. This will also provide a little added height to the speakers, which they would probably also benefit from.

In terms of upgraded power cord - would I get more bang for my buck from an upgraded interconnect? (I'm currently using a $3 run-of-the-mill RCA cable)

Thanks!

I own a dialog II. For tweaks, I added one of the Hi-FI fuzes, with minor effect, and a PS Audio power cable, bigger change.

I really like my amp. You chose wisely.