I hear this has a detrimental effect on the tone, but i have no idea how or why. Post 2 includes a link to a cool piece of amp history, a pdf of ken fischers. Marshall jvm410hjs with a larmar ppimv, post phase inverter master volume with a gibson les paul custom r7 and a 1971 marshall 1960a 4x12 with pulsonic greenbacks. Ive been looking at doing a post phase inverter master volume mod to my 68 fender vibrolux. Dirty potentiometers, squealing and he didnt like that he had to crank it up to. This is the most desirable master volume mod for vintage marshalls and it works great for those who need to reduce their volumes.
The amp also has a professionally added ppimv post phase inverter. When the proper ones are used there is no change in the normal cranked tone. Technisches schroter amplification point to point wired amps. Ive heard one non master volume amp with the larmar ppimv and it sounded great. Its post phase inverter, so it can be used in conjuction with a prephase master, makes. Add a 1 megaohm audio log pot and two wires and youve got an effective post phase inverter master volume. The pre phase inverter master volume is dropped in favor of a trainwreck type3 post phase inverter master volume ppimv. I also tried it in a 5e3 clone and did not like it at all. Scribd is the worlds largest social reading and publishing site. Marshall jtm 45 ri with granger larmar ppiv master volume mod duration. The difference is that with a post phase inverter master volume ppimv, youre hitting the phase inverter with the full guts of the preamp, which causes the pi itself to distort as well. The 5f6a bassman does not have a master volume so you cannot turn it down and still drive the preamp.
Its post phase inverter, so it can be used in conjuction with a pre phase master, makes. I thought markrockstah settled on using a 2203type master volume preamp section i. Pre phase inverter master volume the preferred master volume for cathodyne. Achieved the same, if not better, attenuation without sucking too much tone as my aracom attenuator. This mv is based on ken fishers type ii, with the larmar refinement 2. Issuu is a digital publishing platform that makes it simple to publish magazines, catalogs, newspapers, books, and more online. Another tweak is to move the master volume to post pi post phase inverter. Endstufenverzerrung, post phase inverter master volume kurz ppimv, master volume kontra power soak, true hardware bypass, kabelkapazitat, punt zu. Yeks guide to the fractal audio amp models free ebook download as pdf file. Theres a lot of versatility in an amp that has preamp gain, standard master volume, and a ppimv all at the same time. Many post phase inverter master volumes have the advantage that when turned all the way up they are out the circuit. Types 1, 2 and 3 master volume go after the phase inverter section. Then install a 220k resistor from pin 2 middle pin of the treble pot, to pin 1 of the master volume change the wiring on your two volume pots, and v1 to match a 2203 install a lar mar ppimvthen check that you have pretty much stock 12000 filtering.
Trainwreck type3 post phase inverter master volume ppimv add a 1 megaohm audio log pot and two wires and youve got an effective post phase inverter master volume. Tube selection for 5f6a bassman discussion in amp central station started by. Yeks guide to the fractal audio amp models analog circuits. Another tweak is to move the master volume to post pi post phase inverter in the amp model.
Like wouldnt having the master volume all the way up and using the other volume as just regular volume produce the same effect as having no. I have a larmar ppimv on my 2204 and mainly use it to make the master volume less sensitive. If scaling the phase inverter supply as well, then drive compensation becomes less important but it would be done as you suggest with a pre pi master volume control. Like wouldnt having the master volume all the way up and using the other volume as just regular volume produce the same effect as having no master volume. I assumed it would just mean another controllable variable. Postphase inverter master volume ppiv mv installation in a. The amp also has a professionally added ppimvpostphaseinverter. Tube selection for 5f6a bassman telecaster guitar forum. Ppimv postphaseinvertermastervolume is by far the most transparent mv that can be added to an amplifier, due to its location in the circuit being after the preamp gain stages and phase inverter. Captain amps captain guitars captain guitar parts shop.
With the lar mar master the tone is fantastic at lower volumes because it loses none of the highs. You will lose some tone with the larmar, you may be. In a regular prepi amp, the phase inverter rarely distorts only when the master is pretty high and the power tubes are close to clipping themselves. Ppimv post phase inverter master volume is by far the most transparent mv that can be added to an amplifier, due to its location in the circuit being after the preamp gain stages and phase inverter. Now i use it regularly with the volume turned up to 57 and the master at about 23rds. With the post phase inverter master volume kit, you can install a master volume.
Thus the amp retains its function as a non master volume amp. The metropoulos dvl1 william duvall signature william duvall of alice in chains and george metropoulos have paired up to create the greatest metropoulos amp yet, the dvl1. Easily share your publications and get them in front of issuus. However i find that post phase inverter master volumes need the amp to be turned up more to sound good. A friend of mine had an old, sick marshall jcm800 head which had some issues from sitting in the florida humidity. The trick to retain the stock tone when the master is not used is to use the right value of caps. The choke is moved upstream to supply the entire amp with ripple free power.
Its the ultimate 100watt plexistyle amplifier with maximum flexibility, maximum functionality and zero compromise in components, signal purity, and tone. I was wondering about using what was on the victory v40, since it is a americanstyle tube amp. The original larmar circuit wont affect the trem on that amp. Dec 20, 2015 a friend of mine had an old, sick marshall jcm800 head which had some issues from sitting in the florida humidity. My limited understanding is that it has to do with the master volume being inside the feedback loop in a post phase inverter master volume, and that master volume setting changes also change the amount of negative feedback and how the phase inverter might break over into distortion.
As you turn the master volume pot down counterclockwise more of the opposite phase signals from the phase inverter are mixed together which cancels the signal out. I installed a larmar master in my 66 vibrolux reverb a few years ago and love it. Ive heard one nonmaster volume amp with the larmar ppimv and it sounded great. Stories discover categories issuu store features sign up. Id like to implement a post phase inverter master volume in a 65 fender showman. How to install a postphase inverter master volume in a marshall amp. Say you have a nonmaster volume amp, and youre thinking about installing one. So in a day or two ill be taking my super lead to the tech to get a master volume installed. Ill go out on a limb and say larmar mvs are often used in ltp circuits, so i assume. It was cheap and easy to install, just gives me more options. I was under the impression that post phase inverter was typically looked at as superior, but when i asked the tech about it he said that he thinks you lose too much top end with the post pi, and hence recommended the pre phase inverter. Where you put the drive compensation will depend upon if you include the phase inverter in the scaled power supplies or just the output tube anode, screen and bias supplies.
Larmartrainwreck type2 master volume old school master volume. Links to pdf files will be included in the order status email when the order. When it is turned to max, it is essentially taken out of the circuit ala matchless. It turns out they seem to use a type2 larmar but with a larger value pot, and smaller value safety train wreck type2 larmar on a victory v40.
Slug magazine february 2017 issue 338 by slug magazine. This allows the phase inverter to contribute to the pre master volume distortion and makes the control more useful. I couldnt turn up the volume to where i liked the sound. You can download the editable diylc diy layout creator layout file here.