Has anybody built their stereomour as a 45 amp yet?

[Jim R.]

Just curious if any of you folks out there who have built stereomours have built them as 45 versions?  Anything you care to share, especially if you have also tried it as a straight 2a3 amp, and/or using a 2a3 in the 45 configuration?

Just considering this again, but a bit more seriously this time as I've been running my Cornwalls with my Carina in triode mode, whih is 1.6 watts, and quite sufficient for our space.

Thanks,

Jim

[howardnair]

hi jim--i have not tried the 45's in my stereomour's yet-i built mine as straight 2a3-the caps are 2.7 mundorfs -.1 are jupiters-i can't recall exactly but the resistors 1.6k and i think 4.7k in parallel between 6 and 16u and 10 and 20u- i just used a 1.2k -i used the shuguang 2a3C--i now use the sophia 300B/2.5v meshplate--very happy--i have been thinking lately of either changing to the 45's for a while or buying another stereomour and doing that with 45's--do i like what i hear --yes very much so - the sophia's which were sort of at your suggestion really opened up the sound-- my speakers are a pair of electrovoice  baronets-which are a extended corner horn- that i built using fostex 208 e sigmas and some lcy ribbon tweeters-it was a experiment using the fostex --it worked out well-since you are on the edge throw in those 45's and tell us about it---howie

[Bryon]

Hi Jim

I built a Stereomour for 45's and have used a couple of types of 45's and a couple types of 2A3's in it- but I've just recently changed my cartridge and haven't done any comparisons for a while.  I don't feel comfortable making any comment at the moment other than the Stereomour sounds great with either.

After the game, I'll hook up my sacd player and do some listening comparisons with my son, who hears much better than I do, and post the results.

Bryon

[Bryon]

Hi Jim

The Stereomour is a great amp, which in my experience sounds great with either 45's or 2A3's.  I built the amp for 45's but have used both types of tubes based on the whim of the moment.  I was going to try to write a full fledged comparison between the Stereomour with the two different tubes but then realized that isn't what you wanted. Besides I'm not sure how helpful my impressions would be to you as every system is different.  The Stereomour in my system is being used in a bit different way than most folks will use it as it receives the signal from my Extended Foreplay III and passes it on to my Lowther DX4 drivers in Azura horns which cut off at 200hz. The bass  is provided by an old Kenwood sand amp feeding mini-onkens.  Volume isn't a problem as the speakers have a sensitivity of 100db or so.  I've also changed a few things -no circuit changes, but I used better resistors, 3.3uf clarity cap mr series output caps, a TKD 2CP-2508 pot, and upgraded the rca's and binding posts. 

Given that, I hooked up my SACDmods Sony SCD-C555ES Statement player, which usually is paired with a Crack, to the main system and listened to a couple of tracks: Stravinsky-Rites of Spring and Ella Fitzgerald- They Can't Take That Away from Me, from a SACD-SHM compilation I picked up before Christmas to see if it could compete with vinyl [it couldn't, at least not for me] with Sophia mesh plate 45's and TJ mesh plate 2A3's.

My preference was clearly the 45's, which I thought had a more natural, refined sound, focusing more on the midrange.  I found the 2A3's a bit brighter than the 45's, but my son, who has younger, better ears, thought that the two were close, with the 45's a bit smoother and the upper frequencies a bit better with the 2A3's.  The volume on the 45's was a bit lower but again not a problem in my system.

Over Christmas break, we hooked up the Stereomour to my daughter's ipod and her Heresy's.   She wasn't thrilled with the sound of the NOS Sylvania 45 tubes but loved what she heard with EH 2A3 Gold tubes.  Volume for her was a bit of an issue, but she does like her music relatively loud.  [I actually built the amp for her but she couldn't take it back on the plane so I still have it - at least until Spring Break-yaay.]

It seems to me that the Stereomour will excel with either 45's or 2A3's and the limiting factor might be the quality of the tubes and the system that it finds itself in.  Considering that the required alterations are simple and reversible, I'd say go for it.  I'm more than delighted with the 45 Stereomour, although I haven't heard the straight 2A3 amp.

Bryon

[Doc B.]

OK, temper my comments with the fact that I am at the end of day four in Vegas and I just got back from a great dinner and Hank's Martini and Steaks (yes, I think they must have conceived of that restaurant with Doc B. in mind). I appreciate the comments and I think the most important thing that Bryon said in his very good post was "the limiting factor might be the quality of the tubes...". Remember that one pair of tubes of a given tribe doesn't necessarily tell the whole story. There are 2A3s that sing and 2A3s that suck. Ditto 45s, or whatever.

I'm not trying to curtail the contributions here, even though my blunt comment may seem that way. In fact I am trying to promote the opposite, that we need even more commentary by anyone who has tried the two versions, including what particular brand and structure they tried. As we build a broader database we can do a better job of determining what tube might better float an individual's boat.

The kit is relatively inexpensive, and what I really hope is that it leaves enough dough in everyone's budget to get some of both tribes of tubes so they can try their own comparisons. The best ears to trust are your own.

[Jim R.]

Thanks all, especially Bryon, and Doc for reinforcing the all-important point

Yes, just curious more than anything, but as I already have a good pair of 2a3 amps, I thought it would be nice to build the stereomour as a 45 and just wondered what the folks who have done this thought.  Obviously, the amp is a hit whichever way you go, so I'm going to proceed ass planned and build it as a dedicated 45 amp.

Right now the only 45s I have in the house are a superbly minty and clean pair of National Unions from the 40s, but I will also probably try some sophias at some point, or maybe even some solid plate EMLs.

Bryon, I too have upgraded a few parts -- such as Mills resistors for the PS and 45 bias, some shinkos and caddocks in the CCS, and will most likely bypass the 45 cathode resistors with some film caps.  Also binding posts and RCAs are upgraded and if I don't build it as a straight power amp, I'll probably use a goldpoint selector and attenuator.  The base is coming along nicely, but finishing is stalled due to some cold weather.  The top plate is finally on it's way back to me from the plating shop in the northeast, so when all gets here, I can dive in a bit more, though I've promised myself that I have to finish my Crack first.  Right now I have a nice SE el84 amp running the Cornwalls, but have no functioning headphone amp, and there is also a very nice WE421A on it's way to me, and I'm sure once it gets here I'll want to use it.  My folks gave me a nice AudioGD NFB-2 dac for christmas, and that is what I eventually plan to pair with the Crack.

Anyway, I'm rambling so I'll stop here, but thanks again for the responses.

-- Jim