SET Asylum

Single Ended Triodes (SETs), the ultimate tube lovers dream.

Use this form to submit comments directly to the Asylum moderators for this forum. We're particularly interested in truly outstanding posts that might be added to our FAQs.
You may also use this form to provide feedback or to call attention to messages that may be in violation of our content rules.

You must login to use this feature.

Inmate Login

By default, logging in will set a session cookie that disappears when you close your browser. Clicking on the 'Remember my Moniker & Password' below will cause a permanent 'Login Cookie' to be set.

Moniker/Username: The Name that you picked or by default, your email. Forgot Moniker?	Examples "Rapper", "Bob W", "joe@aol.com".
Password:	Forgot Password?
	Remember my Moniker & Password ( What's this?)

If you don't have an Asylum Account, you can create one by clicking Here.

Our privacy policy can be reviewed by clicking Here.

Inmate Comments

From:
Your Email:
Subject:

Message Comments

Original Message

RE: "EML...are the only ones built right" is simply your opinion...

Posted by tube wrangler on July 11, 2012 at 22:05:13:

No denouncing! That's not the idea, please! It's just an objective discussion of differences that exist-- choose what you like!
S.E. amps have no natural Common-Mode (hum, noise & distortion) rejection.

This factor is why they must be built better, with better parts-- if they are to become anywhere near as good as a cheaper to build P/P.
Superior is when you develop either type to best address the speaker you're driving with the amp.
There are, of course, differences that one should be aware of. S.E. amps tend to tune into narrow bandwidths that tend to center around the values of capacitors that are used for cathode bias and plate supplies. S.E. amps are extremely sensitive to these values. The really great S.E. amp requires-- what some may regard as extreme measures-- virtually "perfect" engineering across a wide spectrum of the amp's design and construction.
If all of the necessary challenges are met, then the S.E. is more musically revealing and sensitive to musician attitudes and emotions-- and is a better replicator of musical depth and layering-- than any other form of amp, especially if the S.E. is simple-- uses only two stages Directly-Coupled together.
So what, you could say? And I might agree-- depends....
The P/P amp has natural Common-Mode rejection-- it eliminates a lot of hum, noise and distortion automatically. It is pretty self-evident that there are artifacts that are a part of (dynamically occurring) music-- that will look the same as hum, noise, or distortion-- to the circuit-- which, being Push/Pull, will naturally reject some of it. ALL Push-Pull circuits do this.
Common-Mode rejection is a form of processing-- it PROCESSES OUT some hum, noise, distortion AND MUSIC.
A Push/Pull amp is far easier to design for a wide bandwidth as each side of the circuit tends to augment the other's bandwidth-- expand it.
Output transformers for Push/Pull circuits tend to self-cancel any tendency for the laminated core to "saturate"-- allowing easy design for wide bandwidth and power in the output trans.
Basically, the best-designed S.E. amp will be under 2 watts or so, Push/Pulls can be anything you want to build to-- in power levels.
To choose one topology over the other isn't the point here-- the point is that tube quality requirements are MUCH more stringent for the S.E. type.
So, why do we listen to S.E. amps at all? THEY DO NOT PROCESS MUSIC-- they can't unless additional circuitry is designed into them to force it. Of course, we're not going to make that mistake with S.E.-- the simpler and more natural it's built to be-- the better it is.
What to like? I use both types of amps routinely. But this is the SET forum!
---Dennis---