2a3's vs. 45's

ALL212

ALL212

New member
I've just ordered my Stereomour and the big decision is which way to build it.  2A3's or 45's?  I understand the power difference.

Is there a vast difference in the sound?  What are your impressions if you've listened to both types of tubes in the same amp?
 
Start with 2A3s. That will create a baseline from which you can determine if 45s are the way you want to go. IMO the 2A3 is more versatile in terms of musical genre because of the power output and bass delivery. The 45 is kind of a longhair tube for those who want see through clarity and black background at the expense of some shall we say soul - that is, James Brown soul, not Catholic soul. That soul thing is why I listen to 300Bs.
 
Thank you, sir!

I will proceed with a 2A3 amp.

Now...just because Doc posted this doesn't mean the rest of you can't attempt to influence me!!  ::)
 
This has to be asked, do you have speakers that will operate on the 45s?  If so, I hear more magic the lower the power.  45s are a great way to go with the right speaker.
 
Paramours...1 pair 2A3, 1 pair 45.  Doc really pretty much nails it....

I listened to both for several month, stock other than the required cathode resistor change, etc. to go to 45.  The 45 is sublime... timbre, imaging, palpable presence...everything is like a fine still life on velvet.  The 2A3's are more dynamic, like the same still life with a spot light focused on it.  300B's have more grunt...double the spotlight and the velvet painting is now Elvis.  (I like my 300B's, but they have remained in the closet for quite a while. A bit noisy on my 102db speakers.  Need to change them to DC heaters!)

Musical genre really plays a role in the selection.  I listen to jazz, blues, female vocals, classical. The 45's are really the best with intimate, small ensemble stuff.  The 2A3's are better when the music is amplified, and the ensembles are larger.  When the blues get heavily amplified or the classical is full force symphony, time for 300B's, or my standby PSE 6L6 amps.  Not that the the 45's or 2A3's are bad on the big stuff, just maybe too polite.

All that being said, most of my attention has been on the 45's, matching them with MQ iron.  Simply hard to not listen to them.  OS 45's are still reasonable cheap, listening to a pair of with 1937 service lables on them.  I also have a pair of Sophia Meshplate 45's that get rotation, but really don't, IMO better the old stock.

I need to look at similar changes to the Paramour 2A3's, either the new BH iron offering or MQ.  I have OS RCA, Sovtek and JJ 2A3/40's, (which to me sound more like 300B's).  The Sovtek's are damn good, especially for the price.  I need to try some Chinese 2A3C's, which are well recommended on this forum. (Grainger is a fan)

So think about to what you will listen and what sonic characteristics make your listening experience special.

Cheers,
Geary

Modify message
 
I've got some AV123 ELT525's that are 83dB @ 1w/1m, a pair of Boston Acoustics A60's at 90db and a few other small bookshelf options.  None of these are stock and all have had crossover upgrades.

I've experimented with some 5w Pass camp amps on my Dahlquist DQ-10's and am amazed at the sound quality.  No - I cannot blow the house down. They are not "near field" but you don't want to get too far away either.

So I'm not expecting to blow windows out - I'm looking for the best sound this amp can put out.

As I'm writing Geary posted so I'm adding...

Female vocalists are what I really like to listen to - instrumentals are a favorite.  I don't expect these to play Pink Floyd or Zeppelin - I've got other amps to handle the heavy work.


Edit - I'm looking for magic out of this amp.
 
Go with the 2A3, you can always change your mind later. I love the 45 and have the speakers for it. I think the 2A3 is a better match for yours...John
 
BTW, I was not contradicting Dan's suggestion of starting at 2A3 and going to 45.  Just saying I think you will prefer the 45.
 
I do want to get to the 45's but I'll start with 2a3's so I know what you guys and gal are all talking about.

Thanks for the guidance. 
 
Remember that you can still put a 2A3 in a 45 amp but not the other way. I built mine straight for 45's but I have a quad of 97db speakers. YMMV.
 
I think starting with the 2a3 first and then trying to the 45 after is the way to go.  I tried all on my Pramounts and my opinion varied from day to day.  I ended up with 45s and went the full route with Magnequest OTs and chokes for 45.  I don't miss the 2a3, but occasionally I wonder if I shouldn't have stayed with the 300B as I liked the oomph it provided.  But that is only when someone mentions it, overall I love playing vintage 30s and 40s output tubes, not an option with 300Bs and vintage 2a3s aren't exactly cheap anymore either.
 
Paul's (Paully's) opinion varies from hour to hour!  We are very good friends and he will agree!

He started out with the 300Bs, then 2A3s, back to 300Bs, to 2A3s, to 45s and I think that made him happiest.  I heard all iterations but not for long times, we live 4.5 hours apart.  I agreed with his opinions, the lower the power the better the detail and lifelike sound. 

His 45s and his Altec model 19s have better bass than any other iteration I remember.  But I am not sure I heard the 300Bs and the model 19s.  Now doubt the model 19s are better in the bass than the Valencias.  (I'm not a bass freak, more a high frequency freak)

As always YMMV!
 
I know the thread is Stereomour, but I'm wondering about the Paramounts, since they've now been mentioned, too.

I always figured the 2a3s would be preferable to 300B, especially since I have very sensitive speakers. No? And how do you wire them for 45s?
 
First response, do a search on converting the Paramount to 45 as there is a lot of very good information in the archives about changing out the two big cathode resistors, etc...  More than I can remember and repeat here.

Second, a pair of 45s will run from $120 to $200 with the increased demand and dwindling supply pushing it steadily upwards.
 
With your listed sensitivity, you are going to have a hard time with 2A3 and beyond difficult with the 45 if you listen at higher volumes. Yes the 45 has a special sound but unless you have the speakers for them you will be left disappointed and looking for new speakers.  Just don't get your hopes up. If you want the magic you need the right speakers. Paully and I are running 19's and they get plenty loud on a watt though I've driven mine to clipping on occacion with my 2 watt SEX amp.

It may be possible to get a 45ish sound with a 300B and that's what I'm chasing now. I'll report back if it ends up successful ;)
 
I didn't even notice the speakers.  His next thread will be asking about Klipsch, single drivers, and Altecs...

But no, I don't think 45s are going to work well from my previous experience with 2 watts on 90db.
 
And neither is a 2A3 very well. SET sound has a price and that's a higher efficiency speaker or listening at a very low level. 
 
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