From jason_stanfield@mac.com Wed Oct 20 15:44:31 2010
Subject:Re: re Speakeasy News

OK .. I needed a little time to wrap my head around it; again, I'm not an engineer so I don't get all the technical aspects of it, but here's my best *layman's* explanation; I wish I could explain it better, but here goes (and sorry for the length; I edited this as much as I could):

It has everything to do with a headphone output being amplified at the source versus the line-level signal produced by L & R outputs. The headphone amp isn't terribly powerful - just enough to drive headphone speakers - but *because* it's amplified, you get dynamic headroom. Line-level doesn't do that; all it does is produce a "dry" signal.

Now, going from a headphone output into a solid-state device -- standard keyboard amps, or effects devices such as the Ventilator -- will demonstrate a slight difference in volume, but not in tone. This is where tubes come into the picture, specifically the way the tubes in the Vintage Pre are engineered to handle the larger frequency, dynamic, and tonal ranges of keyboards (as opposed to the comparably limited response of tubes designed for use with vocals and guitars).

One further difference needs to be noted here: many standard tube preamps have solid-state electronics before the tube, so that dynamic and tonal headroom is cut off, and what is essentially a line-level signal is being "warmed up" some. Those that have experimented with standard tube pres on their 'boards sometimes report that the sound is "stuffy" and "needs EQing". The Vintage Pre is all tube - no solid-state electronics interfering with the signal.

Now, why the upgrade?

A balanced signal is better than an unbalanced signal; unbalanced cables are susceptible to interference and can affect tone. A balanced cable - and corresponding input jack - is going to carry all the tone and dynamics and nuances without interference. Former Speakeasy Pres use standard mono jacks; current ones use balanced (TRS) inputs.

So think about your audio chain:

1. The sound your keyboard generates
2. The sound as it leaves your 'board (output)
3. The cable it travels over
4. The input of the receiving device
5. The handling of that signal in the device itself

If you have a great keyboard, but are going from the line outs over an unbalanced cable into a solid state amp, you're getting blah sound -- from the amplified headphone out (which is TRS) over a balanced cable into a balanced input and straight into a wide-range tube architecture allows your keyboard's *complete* tone to be heard. So your 'board probably sounds great, but you're not hearing all of it - every step in the unbalanced/solid-state chain is removing something from the signal. Again, it's like the guitarist with a $3000 well-engineered axe playing through a practice amp; the subtle qualities of the guitar can't be heard.

Anything beyond that is math to me, and considering Steve breaks calculators trying to figure this stuff out, I doubt he'll do much better; feel free to contact him directly if you need more info.

Jason Stanfield