Everything We Know So Far

The man, the band, and everything else

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Ralle
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Re: Everything We Know So Far

Post by Ralle » Wed Aug 08, 2018 5:54 pm

" The audio clips sound so good...I've got to try this setup. The only thing I can't quite understand is the line out even though you've explained it a couple of times already. What is the impedance of the line out (reference to ground) with the 0.68 ohm setup? The line out I currently have is similar to the one used on the Hotplate attenuator which uses a 5K pot along with two resistors (a 1K and a 470 ohm I believe). "

That works fine as well, but that is the line out I described as the " more common here on the forum ", wich isn't bad in any way... works like charm. The difference lays in the " 0.68 ohm line out; Since that's all I have over the cab/mixer/powerstage or what ever you want to drive, I loose less signal comparerd to having the other setup ( 1-5k/470ohm ) simply cause there's less resistance... Both ways works very well, the one with the less resistance have less lost of signal/freqs or what ever it is... There is an audioable difference, I've tried both.
The impediance ( with the cab ) to ground must be the cabs impediance thrue the lineout; 1x8+1x0.68 and since I happen to have a calculator laying around the result would be... hang on... 0.63ohms... take that in serie with the big on and you get 0.63+8= 8.63 ohm total from the main amp. If I'm using the reamping you do the same calculation with the small resistor and the resistance in th input of either the mixer or the PA head input... and both are well over several k's... you will NEVER go over 0.68 ohms no matter what you do, as long as you hook up the small resistor across the input of what ever your using.
This variant is very easy to build, suppose you have a big load for the mainamp, just hook up a simular resistor ( preferably an effect resistor ) of a small value in serie towoards ground, and hook up your other inputs ( amp, mixer or what ever)... I have an effect resistor of 0.68 ohm ( well actually I have four, two in serie and thos two in parralell, but I still get the same value, I just wanted to be on the safe side powerwise )... :wink:

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Ralle
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Re: Everything We Know So Far

Post by Ralle » Wed Aug 08, 2018 5:56 pm

jnew wrote:
Wed Aug 08, 2018 5:08 pm
I think what he is saying is, if after the load resistor you add another .68 resistor, that would be your line out signal to the Master PA amp. It sounds like a fixed line out as opposed to the 5K pot, 470 Ohm and 1K resistor that you talk about. That is variable with the pot sweep and all. I think his is just fixed with a .68 only. :what:
That is a much better describtion of what I ment... thanx... :wink:

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Ralle
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Re: Everything We Know So Far

Post by Ralle » Wed Aug 08, 2018 6:01 pm

" That would also yield a fairly high voltage output since a 0.68 ohm isn't going to drop much voltage "
There I'm lost... what do you mean by that?
All I know is that the lower the resistance/impeadiance, the lower the volume... in this possition, that is :oops:

Tazin
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Re: Everything We Know So Far

Post by Tazin » Wed Aug 08, 2018 7:59 pm

Ralle wrote:
Wed Aug 08, 2018 5:54 pm

That works fine as well, but that is the line out I described as the " more common here on the forum ", wich isn't bad in any way... works like charm. The difference lays in the " 0.68 ohm line out; Since that's all I have over the cab/mixer/powerstage or what ever you want to drive, I loose less signal comparerd to having the other setup ( 1-5k/470ohm ) simply cause there's less resistance... Both ways works very well, the one with the less resistance have less lost of signal/freqs or what ever it is... There is an audioable difference, I've tried both.
The impediance ( with the cab ) to ground must be the cabs impediance thrue the lineout; 1x8+1x0.68 and since I happen to have a calculator laying around the result would be... hang on... 0.63ohms... take that in serie with the big on and you get 0.63+8= 8.63 ohm total from the main amp. If I'm using the reamping you do the same calculation with the small resistor and the resistance in th input of either the mixer or the PA head input... and both are well over several k's... you will NEVER go over 0.68 ohms no matter what you do, as long as you hook up the small resistor across the input of what ever your using.
This variant is very easy to build, suppose you have a big load for the mainamp, just hook up a simular resistor ( preferably an effect resistor ) of a small value in serie towoards ground, and hook up your other inputs ( amp, mixer or what ever)... I have an effect resistor of 0.68 ohm ( well actually I have four, two in serie and thos two in parralell, but I still get the same value, I just wanted to be on the safe side powerwise )... :wink:
Ok, I got it now...Thanks for clarifying.

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Ralle
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Re: Everything We Know So Far

Post by Ralle » Wed Aug 08, 2018 9:30 pm

No problems... :wink:

DeanUlve
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Re: Everything We Know So Far

Post by DeanUlve » Sat Aug 11, 2018 1:23 pm

Is there a Line Out box available that meets the specs you've laid out, for those of us that are not builder savvy?
:scratch:

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Ralle
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Re: Everything We Know So Far

Post by Ralle » Sat Aug 11, 2018 5:16 pm

I actually don't... I guess others in this forum can awnser that better than me :oops:

Tazin
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Re: Everything We Know So Far

Post by Tazin » Tue Aug 14, 2018 4:01 pm

I had an hour or so of free time so I decided to try a setup kinda similar to Ralle's but using a straight forward Super Lead and a late 70 "Lead" 50w. The overall results weren't too bad although I didn't try any pedals with the setup. Here's what I used:
MAIN AMP: Straight forward '68 100w Super Lead specs with split-cathode arrangement (no oddball parts). Amp setting were similar to Ralle's but with the Treble cut back a little. Guitar plugged into the Bright channel "High" input.
SECOND AMP: A 50w late 1970 "Lead" specs with split-cathode arrangement. Once again the amp setting were similar to Ralle's except the Treble was backed off a little. The Line out from the load box was plugged into the Normal channel's "Low" sensitivity input jack.
LOAD BOX: An Ohmite 25 ohm 225 watt adjustable resistor set to 20 ohms with a Friedman style line out. The Friedman style line out uses a 1K5 resistor along with a 10K Audio pot and a 470 ohm resistor.
So, like I said overall it didn't sound too bad but you can tell the frequencies need a bit of shifting to possibly make it sound better. Therefore, revamping my 50w amp to either a "Bass" spec or "PA" spec may help dial in the frequencies a tad better.

jnew
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Re: Everything We Know So Far

Post by jnew » Tue Aug 14, 2018 5:39 pm

That’s the idea and yes, Ralle is using Plaap specs on his main head, which are specs more aligned with a bass circuit, as is circuit used to re-amp. No treble caps and bypass caps, etc.

I just scored a 69 Super Tremolo so I will use that modded to Master PA specs. :rock:
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plexified
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Re: Everything We Know So Far

Post by plexified » Wed Aug 15, 2018 3:50 am

I'm amazed that this is still going on. Thank God we all are still at it. Here is a few good Vids to demo specific EVH things that are quite remarkable.

First is the JBLs/Greenbacks :

https://www.youtube.com/watch?v=uGSw7jB_0Kg

Second is a demo of effect simplicity and bonus LIttle Guitar Tone @ 4:00 !!

https://www.youtube.com/watch?v=gC9B6kOajEI

I'm going to add to the party with my vote for the Small Power Transformer and The Duncan Custom Custom. I add that because the Power Trans adds a very specific voltage drop that adds sag while keeping the punch for that silky bottom end and the Duncan, because it really tickles the mids and the latest EVH Eruption kind of further confirms the spec at 14.4k. If you don't want that pickup, a PAF with the 'frown' curve eq will still work if you raise the input slightly, or not. The gain structure of the Marshalls can vary a lot, so you don't want mush. You need an axe with lively sustain and enough volume to get that body resonating a bit. Last thing is pure nickel wrap strings. I find it goes with that silky bottom effect. Of course subtle stuff , but it stacks up.

In reference to the clips , they sound great!! You guys remind me of Ken Fischer when he would tweak and mess around. Your already exceeding the original tones and just adding to the pallete. Ken set up a lot of re amp rigs. They always sounded good and were easy to play with more solutions to venues, exactly what your describing. Whats funny is its all in the 'range' of the formula. More than one right combination for a rig that evolved. Komet is building this amp now with the re amp w/d/w the ambicab, might give you some ideas Jnew, http://www.harmonycentral.com/articles/ ... tory-visit
Peace!!! :vh:

Tazin
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Re: Everything We Know So Far

Post by Tazin » Wed Aug 15, 2018 2:56 pm

I had a quick chance to try a couple of pedals (vintage MXR script logo Phase 90 & vintage MXR Flanger) in the front end of the main amp today. The Phase 90 didn't sound all too good in that when engaged there is a decent volume boost and the tone has too much mids (1Khz)...Kinda has that walkie-talkie type tone. So, it's not as plush sounding compared to using it with a normal amp setup. The Flanger seemed to work better than the Phase 90 but I was encountering some stray high frequency oscillations random in nature. Also, the clock timing (or sweep timing if you will) seems a little different acting compare to normal use. Again, this was just a quick twenty-minute test. Also, I didn't put my Echoplex EP-3 in the signal chain so that my change things a little.

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