2a3 or 300b

ditdah · 15828

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Offline ditdah

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on: October 13, 2012, 04:17:09 AM
As the subject would hint to...  I'm at a loss at figuring out which tube to go with in my first Paramount build.  Yes, I know...subjective...  Out of the posts I have read so far...I get the following points:
-2a3's...not as much output as the 300b
-300b's...issue with bass or not as much bass or saggy bass?

Point being...I have no idea which way to go and would appreciate suggestions.  Not sure if it plays into the choice...but I'll be getting the BeePre and using it with this set of paramounts.

Thx everyone

Kenneth Koller


Offline Doc B.

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Reply #1 on: October 13, 2012, 04:27:52 AM
The bass of the 300B Paramount is very good. The differences are that the 2A3 will have a tiny bit more resolution because it is direct coupled, and to my ear the 300B has a little nicer lower midrange performance as well as better punch. I lean toward the 300B with the speakers I use.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline ditdah

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Reply #2 on: October 13, 2012, 04:51:01 AM
Doc,
Appreciate that.  That's what I was looking for.  300b's for me then.

Kenneth Koller


Offline Steve_in_NV

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Reply #3 on: October 13, 2012, 04:49:31 PM
The good news is no matter which way you go, you can always change with a circuit modification.  I originally configured 300B thinking more power, more better.  I then needed something to do, so I changed to 2A3 and haven't looked back since.



Offline debk

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Reply #4 on: October 13, 2012, 11:59:43 PM
I already had a 300b amp so I built mine with 2a3's.

 find the 2a3's more detailed.  The 300b sounds more forceful, but I really like the musical nuances I hear with the 2a3.

Deb

Debra K

Eros 2Phono amp
BeePre2, Psvane ACME 300b
Kaiju, Linlai Elite  300b
Monamour 2a3 amps various tubes
Sota Sapphire, Pete Riggle Woody Tonearm, Kiseki Purpleheart Cartridge
Rega P6 Ania Pro cartridge
Roon Nucleus
MHDT Labs Orchid DAC
Jager speakers


Offline ditdah

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Reply #5 on: October 14, 2012, 12:12:50 AM
I appreciate everyones comments.  Doesn't make my decision any easier though.  I've gone from considering 300b to 2a3 to 300b...and now back to 2a3... again.  
« Last Edit: October 14, 2012, 04:36:38 AM by ditdah »

Kenneth Koller


Offline 2wo

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Reply #6 on: October 14, 2012, 05:29:54 AM
Well remember, it is pretty easy to convert back and forth. your decision is not set in stone...John   

John S.


Offline ditdah

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Reply #7 on: October 14, 2012, 06:19:54 AM
True true...but deciding what to do initially is killing me.  I guess I just need chose one and go go go.

Kenneth Koller


Offline Paul Joppa

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Reply #8 on: October 14, 2012, 04:49:16 PM
I suggest starting with the 300B. The 2A3 arrangement is direct coupled, which is a more tricky approach; the operating points (voltages and currents) of each stage are critically dependent on the other stage. There are just more ways things can go wrong.

As a side note, you can operate the 300B in direct coupled mode, by changing the audio circuit but leaving the filament power alone. This will give you a good part of the nuance available with the 2A3 in this amp, and the 300B will have a longer life when loafing at 15 watts. Many prefer the JJ 2A3-40, which is basically a 300B with a 2.5v filament.

All that said, of course the current Paramount has the new 5670 driver with the new "soft-start" board, which allows adjustment of the critical driver plate voltage. This solves one of the tricky tricky issues the direct coupled circuit.

Paul Joppa


Offline STURMJ

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Reply #9 on: October 14, 2012, 06:37:33 PM
Another thing to consider.  How big is your listening area, and how sensitive are your speakers? If you have a small room or sensitive speakers 2a3 would be the best pick.



Offline 2wo

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Reply #10 on: October 14, 2012, 06:57:29 PM
So, both Doc and Paul say 300B. Careful, it might be a trick ;)

John S.


Offline ditdah

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Reply #11 on: October 14, 2012, 07:08:17 PM
ok ok...I'm done.  300b it is... :P

Kenneth Koller


Offline ditdah

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Reply #12 on: October 14, 2012, 07:18:54 PM
you know...I'm really really really trying to NOT get 2 sets of these amps (money...time...etc...).  However, it would solve my indecision...  wait...I decided...

I'm decidedly indecisive.

Kenneth Koller


Offline Grainger49

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Reply #13 on: October 15, 2012, 12:39:47 AM
Poster Paully has had his one set of Paramounts set up as 300B, 2A3, 300B, 2A3, 45, 300B.  It doesn't take much to swap from one to the other.



Offline johnsonad

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Reply #14 on: October 15, 2012, 01:28:03 AM
You need to base your experience off of your ears listening to your system.  It take an hour or so to switch the amps around per amp so don't lose sleep over it.  Find your own way.  That's what makes this audio journey so much fun!  What sounds good in someone elses system may sound horrible in yours ;-)

I wrote a long thread about my time with the Paramounts and my own experimentation.  In the end, they didn't give me what I needed but it was a fun trip :)  
« Last Edit: October 16, 2012, 08:45:10 PM by johnsonad »

Aaron Johnson