Tube rolling and SAC Glowmaster KT88?

Hiker363, I'm confused by your comments regarding the Svetlana tubes.

SED KT88's with a Winged C logo are made in St Petersburg, and Svetlana KT88's with an S logo which were made in St Petersburg preceeded them and are the same tube. The latter haven't been made for many years.

The current Svetlana KT88 is not made in St Petersburg but is often confused by the unwary with the original "Svetlana KT88". It is not marketed as a SED tube.

As I read your comments I suspect you may have been comparing the current SED KT88 (identical to the original Svetlana) with current production Svetlanas, not made in St Petersburg, and which sound (IMHO) very different and justify your observations about the differences.

Well Hiker, I have taken the plunge and ordered a matched quad of winged Cs so thanks for the benefit of your experience. I'll report back in due course and let you know how they behaved in my particular set up. If anyone else has contributions to make to this thread then please don't consider it closed. This Glowmaster amp is a 'keeper' so I'll be interested in any tweaks, which you feel wring the most out of your unit. I have replaced the stock power cable with a Zu Bok which made a significant improvement and I have ordered some LSU No Spikes (I believe they are called "Spike Sound Will" on the other side of the pond) to evaluate for isolation purposes as the amp is too heavy for both my SAP Relaxa and Seismic Sink.
Of course, any alternative tube combinations i'd be fascinated to hear about...

Hi Mghf, just my thoughts but I hope you'll be as happy as I am after substituting the stock tubes with the Winged C's. To my ears, they're in a different league. Mine sounded better than the original tubes from the off, but really started to come alive and 'sing' after about 40 to 50 hours use, so give them a little time to settle in. Like you, I'd been down the solid state route for many years, and discovered incredible detail but never that elusive something. Then along came valves, and 'another convert is made'.

Interestingly, my first experience with valves was listening to an Art Audio Concerto at Definitive Audio in the UK. My speakers are a little on the hungry side regarding current draw, hence researching and eventually setting on the SAC. Like you, I'd come across the chap who'd had a D200 and his comments also swung it for me.

I've toyed with the idea of NOS 6N1p's but been so happy with the sound of late, didn't really get round to it. If you're interested, have a look on Jacmusic.com - they do some pretty inexpensive NOS 6N1p's.

Newbee, As I'm sure you're aware, there's much politics surrounding the Svetlana brand name. As of present there's...

S Logo (on account of the large 'S' printed on the tube); manufactured at the Refelktor factory, marketed by New Sensor; 'officially' no longer sold in Europe.

Winged C Logo; manufatured at St Petersburg, Russia (These are the real McCoy imho); 'officialy' no longer sold in the US

For what it's worth, the Electro Harmonix KT88 seems to me, on close inspection of the build, exactly the same as the S logo Svets. No surprise really, also being marketed by New Sensor, and made at Reflektor. I could be wrong, but they look carbon copies of one another, just with different print on their sides.

I received my Winged Cs yesterday and plugged them in only to find that despite ordering a matched quad, one was severely off and I was unable to bias it whilst another was just alarmingly off, two were spot on. I suppose I would never have known if the Glowmaster didn't have the LCD display!
Consequently they all went back and I probably won't be able to play until next week now when the replacements arrive (fingers are crossed for a Saturday delivery but that really would be the triumph of hope over experience!).
Thanks for the tip about Jacmusic.com Hiker, I'll check out what they're offering whilst I'm in tube limbo.

I have put a few hours on the "C"s now and I'd have to agree with you Hiker, they have made a great amp even better. Better right across the frequency range and a soundstage you could almost step into. Thanks for your advice, it was much appreciated.