Hello everyone:I've been brainstorming and mulling over many different ideas and topologies for some push pull amps over the last few months. Recently I bought a pair of the Pioneer Pure Malt speakers which have a whopping 82db sensitivity--- hence, you might see the need for some additional power in an amplifier to drive these puppies.
A long time ago I had seen an architecture drawn by Poinz (Eric Kingsberry of Audiotropic fame) that I had found interesting--- take a look---
and thanks bee to BAS for saving and storing this drawing. And to see some of Poinz's eye and ear candy visit his website at www.audiotropic.net.I've always been fond of LTP's for phase splitting--- nice that you can get both gain and phase splitting in a single stage. And with no global negative feedback in our proposed circuit design (shown below)--- this single stage has enough gain to drive the output stage of the tetrodes\pentodes that are moreso commonly used for UL output stages.
And--- truth be known--- I like PP UL amps--- done right they can sound quite good. And again--- in the context of an inefficient speaky--- I need more power than a lovely 45 single ended amp is going to deliver in this lifetime.
So, forward we go--- and I started running some of my ideas for pp by one of my favorite audio buds--- who always entertains my meanderings and musings. And this person always adds a lot of value and critical thinking to the whole process. I really enjoy working with him.
Here is what one circuit we came up with. Keep in mind this is an unbuilt prototype or what we might call a "study"--- neither Kevin nor I can completely vouch for this circuit electrically or sonically. But it should be (my hunch) close to good on all fronts right out of the gate.
thanks Kevin (of K&K Audio) for your assistance, patience, and input. You can visit Kevin's homepages and learn more about what he is up to product wise at http://www.kandkaudio.com/
Now--- the rules of the road---Often times someone does the work and puts up a schematic only to have folks say they would have used tube XWZ or that UL sucks or that PP sucks or that the whole world sucks. All of the above may or may not bee true--- but, honestly, if that is the focus (extent) of your response then I would urge you to post those thoughts elsewhere.
What is and would be appropiate are questions that either Kevin or I could answer or clarify regarding some aspect\function\rationale of the circuit as shown.
I will post later some additional thoughts on component selections in the circuit--- especially as it relates to the magnetics as this is an area I am perhaps a bit more adept in.
In the meantime both Kevin and I would enjoy getting some feedback from you guys such as some comments, questions, constructive criticism, etc.
enjoy,
MSL
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Topic - EL-34 PP schematic - mqracing 22:07:59 02/9/08 (46)
- RE: EL-34 PP schematic - caffeinator 09:00:09 02/14/08 (1)
- approx 30 wpc..... (nt) - mqracing 09:42:58 02/15/08 (0)
- MQ 060 - NewbieBaby 10:07:36 02/13/08 (2)
- and one other quick note..... - mqracing 11:17:55 02/13/08 (0)
- RE: MQ 060 - mqracing 11:10:50 02/13/08 (0)
- Why not help out the phase splitting with the input transformer? - Scholl 16:59:19 02/12/08 (1)
- RE: Why not help out the phase splitting with the input transformer? - mqracing 09:45:01 02/13/08 (0)
- More on fixed bias - gluca 16:14:25 02/12/08 (2)
- RE: More on fixed bias - mqracing 09:49:52 02/13/08 (1)
- Website ... - gluca 09:38:59 02/14/08 (0)
- RE: EL-34 PP schematic - SteveBrown 13:25:19 02/11/08 (3)
- RE: EL-34 PP schematic - mqracing 10:15:52 02/12/08 (2)
- RE: EL-34 PP schematic - SteveBrown 18:15:25 02/12/08 (1)
- On the other hand... - 2wo 20:30:13 02/12/08 (0)
- More puzzling ramblings - gluca 04:08:50 02/11/08 (7)
- RE: More puzzling ramblings - mqracing 10:10:55 02/12/08 (0)
- RE: More puzzling ramblings - KevinC 04:35:33 02/11/08 (5)
- Thanks. - gluca 05:09:52 02/11/08 (4)
- RE: Thanks. - mqracing 11:01:36 02/12/08 (0)
- RE: Thanks. - KevinC 07:06:20 02/11/08 (2)
- "H attenuator" - Russ57 11:06:16 02/11/08 (1)
- RE: "H attenuator" - KevinC 17:11:37 02/11/08 (0)
- RE: EL-34 PP schematic - 2wo 14:32:49 02/10/08 (1)
- RE: EL-34 PP schematic - mqracing 15:21:45 02/10/08 (0)
- Sweeeeet! Just one question - - Mike Spence 13:40:35 02/10/08 (2)
- RE: Sweeeeet! Just one question - - mqracing 15:37:21 02/10/08 (1)
- RE: Sweeeeet! Just one question - - Mike Spence 19:28:34 02/10/08 (0)
- Ver-ry Kewl, Mikey. - Poindexter 09:49:48 02/10/08 (6)
- RE: Ver-ry Kewl, Mikey. - SteveBrown 13:52:31 02/11/08 (1)
- RE: Ver-ry Kewl, Mikey. - Jim Womble 13:13:23 02/14/08 (0)
- RE: Ver-ry Kewl, Mikey. - KevinC 04:39:24 02/11/08 (0)
- RE: Ver-ry Kewl, Mikey. - mqracing 16:28:10 02/10/08 (2)
- RE: Ver-ry Kewl, Mikey. - Poindexter 17:19:55 02/10/08 (1)
- RE: Ver-ry Kewl, Mikey. - mqracing 17:30:42 02/10/08 (0)
- Needs more iron - mwiebe 09:49:27 02/10/08 (2)
- RE: Needs more iron - mqracing 16:10:06 02/10/08 (1)
- RE: Needs more iron - mwiebe 19:11:57 02/10/08 (0)
- RE: EL-34 PP schematic - nullspace 09:08:16 02/10/08 (3)
- RE: EL-34 PP schematic - KevinC 04:47:17 02/11/08 (1)
- RE: EL-34 PP schematic - nullspace 08:05:00 02/11/08 (0)
- RE: EL-34 PP schematic - mqracing 16:14:14 02/10/08 (0)
- Puzzled ... - gluca 05:16:00 02/10/08 (4)
- RE: Puzzled ... - Steve Eddy 11:01:10 02/10/08 (3)
- You're right. - Poindexter 11:20:47 02/10/08 (2)
- RE: You're right. - GTCharlie 04:27:54 02/12/08 (1)
- RE: Output Stage Balance - KevinC 05:41:59 02/12/08 (0)