Hi,

I am now a little nervous about installing a PPIMV in my Plexi clone. I have not heard anything really negative but some say the amp gets raspy and others have recently indicated that one makes a compromise... What does this mean exactly? Does it distort correctly or not? Does it suck tone or does it have a problem like the 'interupt fx-loop mod' which needs buffering?

I currently use a TAD Tonebone set with el84 and a Boss SD1 pedal - this increases the darkness of the Plexi tone but at least it increases the natural gain at a lower volume. I have gotten used to it, but I think what I need is a good distorted glass-like Plexi sound from el34's via the PPIMV. This is what I am hoping it does.

Does anyone have a schematic where I can see how to use a toggle switch for switching circuits between PPIMV and normal?

Cheers Brett

Hi,

here is a snippet from their advert plus some of my comments:- (ps. I am not advertising for them here - I am not affiliated with them in any way...).

Tone bones are converters in the form of a socket which allows replacement of 6L6GC,6V6 GT,5881 & EL34 with EL84 valves. You remove your EL34 and simply plug in the Tube Bone sockets with EL84s - no re-biasing needed at all.

Converters were first brought to public attention by Andy Marshall of THD with his yellow jackets. Amplifiers which operate in Class A mode such as the VOX AC30 have a sonically richer and more responsive tone. Converters allow you to recreate part of this tone with your amp. They also provide a significant drop in volume of between 8 to 30 watts depending on your amp and the tone bone used. Tone bones are ideal for recording, home practice or for small gigs. Two versions of the tone bone are available PENTODE & TRIODE OPERATION.

The main character of your amp will be retained whether it is a Marshall or Fender. In a 100 watt amplifier 4 pentode tone bones will provide around 30 watts and two in a 50 watt head will provide approximately 15 watts. The sound will become thicker with improved sustain (true - I played mine at 7 / 8 and it was a dream come true! Dirty, yet not compressed or choking - nice even saturated tube gain).

Tone bones are supplied in pairs and come with two EL84 output valves

Hi all,

this week I rehearsed with my 1987 using EL84s in a TAD Tube Bone set. They reduce the wattage to about half meaning I can turn up to 7 or 8 without being too loud - just right actually....

Well it was great! The amp was really dirty and sounded really good too. We play quite loud but never loud enough for me to turn up my amp with the stock EL34 tubes - that is too loud! Ideally I need a master volume but I do not want to change the sound. I admit the EL84s are a little darker but some of the Plexi still comes thru.

ps.I have a Power Soak but never use it as I think the sound is compromised - I admit I have not tried it out with the band yet - pending.

Cheers Brett

Hi,

I have a Ceriatone 1987 Plexi and all controls work fine for me - I admit the difference is not like using a Wah Wah but I hear the difference.

I am missing gain and maybe that is what we both expected - I have no MV and I think mine is based on the original 60's models which were tamer than the 1973 models.

Cheers Brett

Hi,

Here in Germany there is a kit maker called Peter Linnemann who sells Plexi kits on eBay for 500 Euro - My pal heard my Ceriatone and was impressed, so he bought a kit from Peter Linnemann with Welter trannies (I know this is not comparable - but he thought all Plexis are the same)- his arrived and we tried the 2 next to each other - his was a lot lighter in weight and I was not impressed with the rear panal layout or the wiring (I think there was a wiring issue too, but that could to do with my pal as he wired a lot of it himself). Yet I was immediately impressed how aggressive his amp was when we switched it on. The volume jumps from 1 to loud and it was dirty straight away - I mean really dirty, which could surely not be main tube break-up... we do not think he has a cascade mod and here is no master volume. I do see some Plexi re-issues on youtube which are dirty at low level.

My Ceriatone 1987 starts to break up at 3 - which is loud! At 4 it is probably almost at its loudest but this is already silly loud. My pal thinks he has a bright cap on his volume knob - can any one tell me if that is all it takes?

ps My Ceriatone 1987 sounded better at louder volumes - I think my pal needs to check out his wiring! Ha!

Cheers Brett

Hi,

building a 100W and then reducing it to 50W by removing 2 (outer or inner) tubes is not the way to do things.

Sure, reduce the speaker Ohm to half and it will work but the sound and performance? The difference in volume between the two is about 3dB - +/- - so you will not get much benefit.  The 100W was designed and tested to get optimal performance with 4 tubes - hundreds of professional technicians and top guitarists tested this setup - possibly thousands by now...  It was never designed and approved to run on 2 tubes. I don't know many players who have claimed it performs good in this mode - sure, many have used it to finish a gig running on 2 tubes,  but I have not heard any 'astounding' positive reports.

I am not a technician and do not know if there is a technical benefit,  There is always someone in a forum who does it, but I personally would avoid this as a default setup.

Cheers Brett

hi,

Does an original Marshall 1987 breakup earlier at lower volume? I have seen some youtube videos of original 50w Plexis breaking up about 3 or 4 - real dirty. The Ceriatone stays ruggedly jangy/light crunchy up to 4/5 and that is deafeningly loud!

Would is the cause of this? (if I am not mistaken of course - I do readily admit that could be a hidden powersoak connected on some of them.

Cheers Brett

Hi,

I stopped using my interrupt loop as I was not happy about the sound nor was I happy about the volume LEDs going into red on my Rocktron Intelliflex. I also have a standard stomp pedal (delay) and at high volume it's on/off LED starts blinking - even when it is off.  I read the forums and deduced that I need a buffer - transistor or valve. I have read that the signal now is approx +2db and with some +4db pedals this is too little (me thinks...). You can fiddle about with the rack settings -10db/+4db and adjust the input/output volumes accordingly but I began not to trust it.

I left it without adding a buffer and now don't use it at all... I have an o/d pedal up front and add my stomp box delay pedal last in line - this works as it is after the o/d pedal. I do not get too much breakup with my Strat so the desired 'place after the preamp stage' is redundant. If I was to play on full with a Les Paul then that would be different as there would be gain at the preamp-stage.

Cheers Brett

hi,

both are great - I like the 50w as it breaks up just a little earlier than the 100w - this means I can play some songs at rehearsal with the dirty sound without pedals. The 100w stays clean/jangly just a little bit longer.  However I often play with a Strat and the 50w will not break up early enough so I need a pedal.  Both are silly loud with a 4x12 box so do not worry about having enough vlume or push - these are loud!

Cheers Brett

Hi,

I play in 2 rock bands - both are very loud - both have very aggressive rock drummers with real acoustic drum kits. To get above their volume level I need to be forceful and connect to one or two Marshall 4x12 1960 boxes.

I have a 100W Marshall DSL and recently sold my old 100W JCM900 for my Ceriatone 1987 Clone. In both bands we play at regular high levels- my DSL is a 100W amp and is very loud - I play it on 3/4 to get to that group level yet it will go much louder. My old JCM900 was 100W yet was not as loud at 3/4 - I needed to have that on 5 at least, but then it was at highest level - it would not really go louder, just more produce more sustain.

The Ceriatone is 50W and is 3dB lower - a fairly common value to describe the diffence between the two 50/100W amp ratings - ok. - not for all amps but you get the gist... Volume is non-linear on a valve amp - it will not continually go louder when you turn one up - they reach a peak and then start doing something else.

My Ceriatone easily reaches group level at 4 - impressive - but mine does not go much louder, from 4 onwards it delivers just more sustain & brown sound. I do not get much noticeable volume difference between 5 and 8. This is very loud and I use a Marshall Guvnor2 pedal for the added sustain too.

So how loud is your band? Do you use overdrive pedals? Do you have a 4x 12 Marshall box?

If yours is simply not loud enough or it is giving you a linear volume then you may have a tech- problem, otherwise I would investigate your speaker box(es).

Cheers Brett

Dear all,

I want to thank everyone for your helpful ideas, tips and support - you are very kind - thanks.

I bought my Ceriatone on fleabay some months ago. It arrived without a cabinet and a corner was cracked in the right corner of the front plexi 'glass'. Well, can't do much about the cracked plexi, but with your helpful advice I managed to wire up an interupt fx-loop straight from the schematic which works very well and I build a head cab myself. I got the tolex, piping, logo etc. online from Tube Town who were VERY fast with delivery here in Germany (http://www.tube-town.net/index.html). 

I am not an expert, but I am quite proud of the result and it cost me under 100 Euro to build...

And it sounds fantastic!!!


Cheers from a very proud father!

Brett

Hi,

just an update:

my gaffa tape has come off on the side where the topmost plate on the transformer has lifted the most (3mm) - I guess the pressure was too much. Anyway the amp still works - so, at least I know the slight lifting up of an arm on at least one side does not affect the amp. The other side is still being held by gaffa tape.

I would still like to know if this might become a problem though... Please feel free to look at the picture at the top of this thread.

Cheers Brett

Strange. I took the amp back out of the case/cabinet and I stuck down the two arms of the top plate on the tranny with Gaffa band which may (or may not have lifted from the rest of the block- this may still be absolutely irrelevant). No change.

Fed up I went away for an hour and came back. I saw the top armplates were not 100% flush/down so I stuck more tape - ok. I tightened one of the 2 bolts which hold down the yellowish looking transformer near the Treble knob. Maybe I caused it to become loose. Who knows...

I left out out of its case/cabinet - it worked.

I am now wondering what this was. I would appreciate any answers to the transformer question as the tranny pictures from Ceriatone show both flush and possibly raised top plate arms. Hmm... otherwise It can only be the yellow tranny bolt - which I do not believe.

Cheers Brett

Hi yet again,

I built my fx-loop interupt mod and it finally worked fine (see other mail). I packed the amp back into it's case and switched it on - the main switch went on, the tubes glowed nicely but when I went to standby there was nothing - deadly quiet.

I removed the amp and checked my mod again - everything in place. Then I noticed that the left most of the 2 arms on the top plate of the fat transformer on the left side were slightly in the air as if they had lifted from the rest of the block (see pic) - I no longer know if this is normal or whether I have knocked them by accident. The left side is definetly 2mm higher than the other.

Q. Is this irrelevant? If yes then I have obviously loosened something else.
Q. If not, then may I tape down the two arms of the plate with let's say Gaffa Band? Is there a lot of heat there?

Cheers Brett

hi again,

I rewired the joints just in case and it worked. Maybe one of the contacts in the jack was left open as I oiginally tried with no fx-unit - however it is correct now. Those jacks are definetely interupt (switchable) jacks nd it sounded great with my Rocktron Intelliflex LTD.

Cheers Brett