EP-PRE revisited

[T.J.Fuller]

Has anyone tried two EP-Pre's in series? Ed used two EP-3's, at least he did live. it's a worthy experiment

A worthy experiment ...Hell, that's a great idea for yet another pedal!

the EP-PRO

2 knobs - you can engage one or both simo

....someone call Peter....

[motrock]

Has anyone tried two EP-Pre's in series? Ed used two EP-3's, at least he did live. it's a worthy experiment

A worthy experiment ...Hell, that's a great idea for yet another pedal!

the EP-PRO

2 knobs - you can engage one or both simo

....someone call Peter....

Cool!

[Good Guest]

Has anyone tried two EP-Pre's in series? Ed used two EP-3's, at least he did live. it's a worthy experiment

Yeh I have tried breadboarding two in series during the robin thread period .... it hits this boost range that doesn't really add anything more like it limits and clamps the signal to one level adding valuable compression that the single knockoffs fail to achieve. Never the less it walks over the single ep3 for boost , color, etc.

BUT What is really important and shows me these guys got it all wrong is the output signal is now in phase with the input signal. In all these knockoffs they don't take that into account ....looks like from all the pics they also leave a lot of tone coloring circuitry out and are just looking at the boost factor anyways.

I call mine the 2P3 " Be like Eddie and use a 2p3" I used J-309's ...It is true tho that it reduces noise from a mxr 6 band...more acurately it replaces what we hear as noise from the 6 band with tone , hence less noise more tone...or better s/n ratio Maybe if time allows I'll do a clip....amps are on the bench getting there annual tune up....but there is a nano head laying around I can use...yeh I'll use that..should be fun to hear Eddie like tones coming out of one.

edit: Oh yeh that so called 3-D tone is the "out of phase" tone you get when you don't use something else to place your signal back in phase.

[harddriver]

Has anyone tried two EP-Pre's in series? Ed used two EP-3's, at least he did live. it's a worthy experiment

Yes, I run two in series as Robin L stated. With that setup is does give some more boost and it thickens the tone up some more. It is a noticiable gain loss when I switch one out. I usually just use one EP-PRE when I am using my EP-3 echoplex. Supposedly Ed only used one Echoplex for recording VH1, and used two EP-3's for the 78 tour. One or two they really have a nice affect to your tone period.

Mind you the EP-3 circuit actually dampens/rolls off some of the natsy top end and makes it sweeter because of the high output impedance same as the original EP-3.

I wonder if the Exotic retained the high output impedance as well?

Sum of all the parts gentlemen, goes into Edward tone, you're playing prowess helps too!

[Good Guest]

I doubt they are paying much attention to the output impedance....to get it right you would have to use the identical fets with the isame drain resistance value, something all the other replacements would probably require changing...not that it's impossible but I just can't see them going thru dozens of fets to find one that has the right output z....I can't even see me doing that

[harddriver]

I doubt they are paying much attention to the output impedance....to get it right you would have to use the identical fets with the isame drain resistance value, something all the other replacements would probably require changing...not that it's impossible but I just can't see them going thru dozens of fets to find one that has the right output z....I can't even see me doing that

Peter Clinch does go through his JFET inventory and tests them to meet the specs he needs I guess he has a high reject rate JFET wise. The EP-PRE is true to the EP-3 circuit and it has the high ouput impedance. From the Clinch EP-PRE owners manual:
"In keeping with the design of the original tape echo unit, the ouput impedance is high. If it was low, it wouldn't have the characteristic tone."

"The EP-PRE is not an exact clone of the original preamp. For starters, I couldn't find any of the original TIS58 JFETS, so I found a close equivalent in a currently available JFET. Because the preamp is a part of a larger circuit, it was necessary to make some changes to simulate the circuit interaction that happened in the original unit. The original circuit operates on a Zener stabilized 20V power supply. I elected to use a charge pump circuit that provides around 17.3V with similar internal impedance characteristcs to the Zener supply, so that the pedal can be operated from a standard 9V pedal power supply."

"I began to seriously analyze the behavior of the circuit, and found that, apart from a small amount of top and bottom cut, the circuit had a non-linear phase response. I believe that this phase response is the secret of the magic tone."

[spaceace76]

I doubt they are paying much attention to the output impedance....to get it right you would have to use the identical fets with the isame drain resistance value, something all the other replacements would probably require changing...not that it's impossible but I just can't see them going thru dozens of fets to find one that has the right output z....I can't even see me doing that

if you look at the schem of the Xotic I posted a while back, it actually has an output buffer so the output impedance is very low in comparison to the EP-Pre.

[leadguy]

Ed used 2 Echoplexes on ATBL (hint hint VH1) and probably on Atomic Punk and might have had the 2 Echoplexes connected in his chain for the whole of VH1.
The ATBL Echoplexes are set for around 100ms and 300ms delay, see the sinas1 ATBL thread.
He could have had them hooked up in parallel (using splitter cables) with each Echoplex going to one of the two Marshall input channels.
Ed was using splitter cables and Rudy says so as well.
On the slow clean guitar just Ed and Dave section on ATBL I think the 3D effect of the Echoplex(es) is pretty easy to hear.

The JBL's are not used for VH1 according to the frequency spectrum analysis, just a Celestion cab with 2 different mic positions, one mic picking up more treble and one mic picking up more bass.

Ed and Rudy say no slaving on VH1 and running 2 Echoplexes in FRONT of the amp makes sense. Slaving without a Echoplex sort of emulates some of the 3D aspect of the Echoplex preamp so put 2 Echoplex pre's in parallel or series (probably parallel) in front of a stock Plexi and there is the 3Dish tone that slaving can emulate but there are other things as well like the Sunset Sound reverb room etc etc.

Any one JFET preamp connected in a Common Source way will give a 3Dish sound really.
Check this out for a more detailed explanation of a JFET preamp http://runoffgroove.com/fetzervalve.html" onclick="window.open(this.href);return false;

[paulscape]

Has anyone tried two EP-Pre's in series? Ed used two EP-3's, at least he did live. it's a worthy experiment

I have been thinking that the results would probably blow us away. I have been thinking that the amount of gain on the first album was due to that! The once you get those greenbacks combined with the JBLS.... its nailed!

When he was playing live in Japan 1978 there's pics of him using two EP3's, both with Boss EQ pedals set to frown curves. They look like they are both setup to be IN FRONT of the amp. Its likely he had one setup for a mild slapback delay and basically permanently on for the pre-amp effect and the other set for a longer delay for songs like ATBL/eruption/AP. The EQ pedals can also add boost and some mojo. I use my MXR 10 band for this purpose...it not only gets more hair on the mids and attack with my plexi but the gain switch (set just above neutral) adds a little more of that VH1 distortion sound. Worn in Greenbacks help

The Ep3 was a definate part of his gain. When he recorded beat it and starfleet he turned up with a marshall head and the EP3. If it wasn't important he wouldn't have bothered with it Id imagine.

[spaceace76]

Listening to some of the Iso tracks I'd have to agree all the time based effects are in front of the amp, at least early on. The preamp of the EP-3 isn't bypassable, if you're plugged in it's in your sound. So two of them in series is definitely going to add quite a bit of hair

[vanhalen5150]

I got my EP-pre today. I have to say, it's not a subtle effect like some say

With the EP-pre in my signal chain I'm actually starting to believe that Eddie's amp might have been stock. It really adds some crucial components to the sound (slight boost and some hair). I really like it. I tried it with a cascade and stock. It sounded better with a stock setup.

I never knew the EP-3 had such an effect on the sound.

Next step: get another one and put it in a slave setup with a good echo pedal

Exactly. Its a common circuit with a fet. But it does what is claimed and expected.

[vanhalen5150]

That's what the EP-pre does: just a slight boost. But, it's just enough. Consider the fact that slaving adds some gain, and maybe a second ep-pre in between the two amps and you don't need a cascade anymore. All the gain you need is right there.

I was messing with the Xotic last night with the Variplex slaved into a 59 circiut build. With the Variplex dim'd I tried the Xotic at 8/12/4 o'clock. At about 11 o'clock the thing sounded perfect. As you start going above that, the gain was too much for Edtone. Backing of the volume of the variplex you could increase the Xotic. Basically it has more gain than needed.

[jape88]

Guys help, anyone got both the clinch and the xotic?
I'm in for a chance of getting a used clinch but it's gonna cost me more than a new one! just wanted to see what you guys would shoot for xotic or clinch.

I've sorta given up on getting a reply from clinch, shame as it sounds like a great product.

[leadguy]

Any FET preamp will give similar results to the EP3 preamp.

Like this one with no volume control that seems to use FET's http://windworksdesign.com/music_fet.html" onclick="window.open(this.href);return false;

There is nothing special designwise about the EP3 FET preamp, a FET preamp is a FET preamp.

Some people just charge more than others for a FET preamp.

[spaceace76]

Very true leadguy. I'm surprised people pay over $200 for a SHO, which has about 10 components in the entire circuit. I'm even more surprised that they pay that much for a circuit that crackles