What's the best 417A & 437A?

Triod lover · 23rd January 2007, 02:27 AM

Am looking for a driver stage to push my 300B se amp,which one is the best driver to drive my 300B via NC-20F interstage!!!
Thanks and Regards,
Triod Lover.

arnoldc · 23rd January 2007, 02:48 AM

Do you mean differences between 417A variants?

I have Raytheon 5842, Amperex gold pins 5842 and Western Electric 417A. Price no object, I like the Amperex on my 45 amp better than the two others, which are very good in their own right.

I do not own a 437A (how I wish)

CLS · 23rd January 2007, 03:06 AM

As to 437A, how about 6S45 (6C45) instead? It's much easier to get & much much much cheaper.

It's choke loaded & driving my 300B, working very well.

Brian Beck · 23rd January 2007, 02:11 PM

Or, a triode-wired E810F/7788. Comparable in mu and gm to the 437A and 6C45, if not a tad more of each parameter. The 7721/D3a has a higher mu, but belongs in this "super tube" category too.

Also, although paralleling tubes has its own set of problems (and detractors) , two 417A/5842s in parallel is close to a 437A, at least in terms of specsmanship. Might be worth a try if you can achieve good current balance with two matched tubes.

23rd January 2007, 02:27 AM	#1
Triod lover diyAudio Member Join Date: Oct 2006	What"s the best 417A&437A Am looking for a driver stage to push my 300B se amp,which one is the best driver to drive my 300B via NC-20F interstage!!! Thanks and Regards, Triod Lover.

23rd January 2007, 02:11 PM	#4
Brian Beck diyAudio Member Join Date: Dec 2004 Location: South Florida, USA	Or, a triode-wired E810F/7788. Comparable in mu and gm to the 437A and 6C45, if not a tad more of each parameter. The 7721/D3a has a higher mu, but belongs in this "super tube" category too. Also, although paralleling tubes has its own set of problems (and detractors) , two 417A/5842s in parallel is close to a 437A, at least in terms of specsmanship. Might be worth a try if you can achieve good current balance with two matched tubes. __________________ Brian

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
437A testing	JDecker	Tubes / Valves	0	11th March 2008 06:31 PM
Output Transformers for WE-437a WOT Line Preamp	snoopyma	Tubes / Valves	4	28th January 2005 01:47 PM
Substitute for 5842/417A	Peter Menting	Tubes / Valves	14	10th December 2003 09:55 AM
417A Line Amp	apassgear	Tubes / Valves	51	31st March 2003 01:23 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read

23rd January 2007, 02:48 AM	#2
arnoldc diyAudio Member Join Date: Apr 2003 Location: Makati	Do you mean differences between 417A variants? I have Raytheon 5842, Amperex gold pins 5842 and Western Electric 417A. Price no object, I like the Amperex on my 45 amp better than the two others, which are very good in their own right. I do not own a 437A (how I wish)

23rd January 2007, 03:06 AM	#3
CLS diyAudio Member Join Date: Jun 2005 Location: Taiwan	As to 437A, how about 6S45 (6C45) instead? It's much easier to get & much much much cheaper. It's choke loaded & driving my 300B, working very well.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)