Fender Prosonic Combo amp

[Destructobot]

I'd be pumped if I was the guy who just got the twin, but I play a lot of surf so that's to be expected. Are they really THAT bad to move around? I carry my 4x12 up and down stairs by myself, can't be any worse than that.

[ghbaudio]

I agree that the Custom Shop name doesn't mean much - it's more about marketing. But the first 250 Custom Shop Prosonics were made in Lake Oswego, Oregon and were hand assembled. The quality of the resistors and caps are of a much higher quality than the Professional Tube Series made in Corona, CA. That's a fact. I've seen the chassis for both side by side and Fender used more affordable parts in the later run. The Prosonic's designer Bruce Zinky as well as Andy Brauer both agreed that the Prosonic Amplifier, especially those original ones from the Fender Custom Shop were very well made, had great sound and are very rare. I'm not bagging on the Corona Prosonics, just stating there is a difference, and there was a number of Prosonics that were classified by Fender as Custom Shop amps.

 

Straight from Wikipedia "Designed by Bruce Zinky as a project for the Fender Custom Shop, the amplifier later had a non-Custom Shop production run at the Fender facilities in Corona, California."

 

The true Custom Amp Shop Prosonics are hard to come by. You know you have a Custom Shop Prosonic if it has four things.

 

1) Says "Fender Musical Instruments" under the jewel light.

2) "Fender Custom Amp Shop" at the bottom of the tube diagram in the back of the amp.

3) The serial number that starts with LO instead of CR.

(Note: Some of the early Corona models had LO serial numbers)

4) The jewel light is Green. (most Professional Tube Series had a red jewel unless changed)

 

If the amp doesn't have all these things it's most likely a Pro Tube Series model. Fender used over left over parts from the Lake Oswego factory but they all seem to have the "Professional Tube Series" faceplate. I did see early Corona production with LO serial number, but not the internal parts or other markings. Only 250 total units came out with the Fender Custom Shop designation and of the quality level Zinky wanted. Ask anyone that's owned an early Prosonic. The hand building and higher quality parts are what make the early ones more desirable, not the Custom Amp Shop label.

 

And lastly it's the Custom Shop models that the three mods are for. The Reverb was noisy, the channel switching did pop sometimes, and one wire needed to have a shielded wire as a replacement to reduce hum. I've done all three and thought the wire replacement and Reverb fixes were good, but forget the pop fix as it changes the tone in a bad way IMO, and the pop is still there just less. You don't hear the pop in a live setting anyway. The later Professional Tube Series didn't need the mods as they became standard production.

[jake.lind]

 

I'd be pumped if I was the guy who just got the twin, but I play a lot of surf so that's to be expected. Are they really THAT bad to move around? I carry my 4x12 up and down stairs by myself, can't be any worse than that.

 

 

Have you ever moved a twin? 4x12's are bulky, but twins are crazy heavy. For reference, a JVM 4x12 weighs about 48 pounds, or the same as an AC-15. I guarantee any twin is going to weigh 70 pounds+

 

So think about lugging a 6x12 up and down steps in a 2x12 size. Not so much fun.

 

(Trust me on this, I have a 4x12, an AC-15 AND a Twin. Twin stays at my house, and the Vox and half-stack come with me whenever I go anywhere. should say something.)

[NoirAbattoir]

With stock tubes, yes, the overdrive channel can be a bit brittle and sterile sounding. There is a ton of gain available, so it's best to load up the drive preamp with lower gain NOS tubes. I did, and it was a firebreathing dragon of natural overdrive tones. In fact, I kinda missed mine after selling it so I've purchased a Supersonic which is one the way as we speak. It's extremely versatile.

[peehoo]

There was a lot of debate about custom shop and non custom shop Prosonics.

 

It seems that it's all a myth. The guys at Fender Forum emailed both Fender and Bruce Zinky and both replied that there NEVER was a custom shop Prosonic line. The production only moved from LO to CO. They were custom shop designed though.

[ghbaudio]

The problem with forums is people ignoring facts to make a point. The guys on the Fender forum can state whatever they want but it won't change reality. There is lots of info online and in old Fender Amp Catalogs which talks of the

Custom Shop Prosonic and the Professional Series Prosonic. I not only own a 1996 Custom Shop Prosonic - I've seen the chassis for both side by side with my own eyes. There's a difference. It's the same circuit but but Fender's

bean counters cut some corners to lower production costs. Fender is famous for their "race to the bottom" build quality. Every year Fender finds ways to make amps cheaper while keeping the retail cost the same. Just look at Fender's new Super-Sonic amp. It's suppose to be Fender's updated Prosonic. No less than 5 circuit boards in the chassis. The preamp sockets are plastic instead of ceramic. The pots and jacks are all mounted to one circuit board instead of hand wired (means you have to remove all the pots and jacks to change any one). The resistors are all 1 watt carbon film instead

of 2 watt flame proof metal film in the critical areas. No tube rectifier or class/power switching. Fender even has ribbon cable running right over the top of the power tube sockets where theres lots of heat. Hardly seems like it was built for quality, road use or to be easily serviced. Increasing profits maybe? Fender has know for years their biggest competitor is used Fender products. They're not going to shed any light on this for you.

 

Last night I called a gentlemen I met in Sacramento that' been friend with Bruce Zinky since they were 15yo. He owns one of Bruce's original Bassman 50 watt modified amps (he said it was Bruce's specialty at the time) and a 1982 JCM 800 50 watt that Bruce rebuilt into a vicious amp. He said the JCM turned out so good Bruce asks him about it every time they talk. He wanted to collect another of Bruce's amps and wanted a Prosonic. Bruce told him to get one of the early models that say "Fender Musical Instruments" on the faceplate with a LO serial number. Bruce told his friend they were all assembled by hand in Oregon and were over built.

 

Another thing he said Bruce told him which I haven't seen on any forum is that Ron Wood (and to a lesser extent Jeff Beck) both gave Bruce input on the Prosonic while it was being developed. He said he didn't think they were ever credited for that, but both Ron and Jeff had early prototypes and worked with Zinky and gave him feedback.

 

If you want to try to rewrite history and state there's no Custom Shop Prosonic, go ahead. If you want to know the truth do your homework. Go dig up some old 1996-1998 Fender Amp Catalogs or talk to Bruce Zinky yourself.

 

Here's some well know sites that are spreading this "myth" as well.

 

Ampwares from their "Fender Amp Time Line"

 

From Wikipedia, the free encyclopedia: Fender Prosonic

 

Fender-Amp.com A Fender Tube Amp Timeline

 

All of the sites mention that the Prosonic was first a Custom Shop amplifier and later had a non-Custom Shop run.

[peehoo]

Well, I seriously don't know. I'm just telling what I heard/read. There seem to be two sides and both are claiming they got their info straight from Bruce Zinky and/or Fender. I've also heard that there were some early Prosonics with 12" speakers.

Some say the Custom Shop ones are point-to-point.

 

So basically I won't claim anything until I see the facts. You might have seen them and know for sure... No offense but from my perspective what you are saying is just another thing I read on the internet - the very thing we both agree won't change the facts

 

I know for a fact that even the older ones say "Fender Custom Shop" on the board. Here is the only picture of the Prosonic I found on the web. It's a later one that says "professional..." on the chasis

 

I'm interested what are the specific differences between this one and the supposed earlier ones. If someone can post a picture of the earlier one we will sort this thing once and forever

[ghbaudio]

Here's a book that backs up what I'm saying. Go to Google books and you can read the page I'm talking about in the book preview.

 

Fender Amps: The First Fifty Years

By John Teagle, John Sprung

 

On page 139

Custom Amp Shop 1993-present

 

On page 141 right next to the top of the line Dual Professional

 

Prosonic

 

"The latest from the Custom Amp Shop is the

Prosonic-an amp that never was, covered in colors

and materials that never were. In addition to the

eye-catching appeal of the chicken-head knobs and

lizard skin covering (Sea Foam Green, anyone?),

this amp has some sonic pleasures to offer: Two

foot-switchable channels (Vintage and Drive), the

later of which offers dual cascading Gain controls

for tailoring your overdrive just so; tube-driven

reverb; and a three-way rectifier switch that

includes the operation of Class-A/cathode bias

operation, a la Vox AC30. Fun times lie ahead for

this line!"

 

This info as well as a lot of info in this book is just

Fender Catalog reprints -this one from 1995.

 

But I will take some chassis pics of my amp production: GA

G = 1996

A = Jan

My amp says "Fender Amp Custom Shop" Scottsdale, Arizona

on the tube chart.

[peehoo]

Yeah, but that doesn't really mean that there were two versions. Like I said, even the later ones, the ones definitely not build in the custom shop had Fender Custom Shop printed on the pcb... It just means that they were designed there. Much like the Baja Telecaster: says Custom Shop but was only custom shop designed...

 

And as far as I know, the factory in Lake Oswego was a regular Fender factory, actually a factory that was previously Sunn, but Fender acquired it when it bought Sunn.

 

The amp custom shop is in Scottsdale, Arizona, where all Custom Shop amps are produced. It could be that the Prosonics were produced in Lake Oswego in a special custom shop section of the factory where only Prosonics were build, I don't know. But it's not THE Custom Shop where all the other Custom Shop amps come from...

[ghbaudio]

Talk about taking hair splitting to the Olympic level, Geez....

 

 

I've shown multiple websites that state the Prosonic was first a Custom Shop amp and then quickly moved to the Professional Tube Series. I've shown you a book with Fender catalog reprints from 1995 that show the Prosonic was classified by Fender as a Custom Shop amp. The tube chart in my amp say Fender Amp Custom Shop Scottsdale Arizona. The amps were even made in different factories with different parts and faceplates. That alone is enough to make a difference between the earlier ones and make them more desirable and effect resale value. Not to mention there's only 250 of them.

 

I'm having a friend come by today with a macro lens so we can get good up close pictures of the things I'm talking about. Right off the bat I could see different tone caps, mine has ceramic tube sockets instead of plastic, different gauge wire, 1000v rated disc caps, etc...

 

Like I said from the beginning --if you read my earlier post--that the circuit is the same, just Fender cut some corners on the parts to save money. Read user review online. Many players other than me hear a difference between the two models -some of these reviews going back years. But I'm sure these players, websites, and the Fender book with ad reprints are conspiring with me to promote this "myth".

 

I'm not argumentative normally, but I think that spreading bogus information devalues the early Custom Shop Prosonic. Many people read these blogs and take the info as fact. Much like the info from the Fender forum which has obviously created so much doubt that even Fender catalog reprints from the time are being debated = ignoring facts.

[peehoo]

The fact is that it was never build at Fender Custom Shop facility.

Well, as far as myths are concerned, I feel the opposite. Early Prosonics may have used better components whatever, but it's a myth that they were built at Fender Custom Shop. Until I see one that says on the back "Created by: Fender Amp Custom Shop Scottsdale, AZ" like all the Vibrokings, Tonekings etc I just don't believe it.

[RoboPimp]

who cares

[peehoo]

 

who cares

 

 

Yeah, that too. We are taking it a bit far:p:lol:

[ghbaudio]

That's not a fact! If Fender was building amps designated Custom Shop at Lake Oswego Oregon then it was part of the Custom Shop facility at that time. These amps existence proves an amplifier doesn't need to be made in Arizona for Fender Corporation to designate it a Custom Shop. That position could be up for "the weakest argument of the year award" anyways.

 

Besides, I thought we were trying to discover if any of the Prosonics were actually Custom Shop Amps? Uncover whether it's a myth or not.

 

Everyone will see the pics soon enough.

[ghbaudio]

Here's pictures of my 1996 Fender Prosonic Custom Shop amp. I've taken pics of the chassis, serial number (I blocked some it out for privacy), faceplate, and tube chart.

 

Enjoy!

 

http://i271.photobucket.com/albums/jj125/ghbaudio/ProsonicchassispicsL.jpg

 

http://i271.photobucket.com/albums/jj125/ghbaudio/ProsonicchassispicsR.jpg

 

http://i271.photobucket.com/albums/jj125/ghbaudio/ProsonicFMI.jpg

 

http://i271.photobucket.com/albums/jj125/ghbaudio/ProsonicLO.jpg

 

http://i271.photobucket.com/albums/jj125/ghbaudio/Prosonictubechart.jpg

[peehoo]

That's not a fact! If Fender was building amps designated Custom Shop at Lake Oswego Oregon then it was part of the Custom Shop facility at that time. These amps existence proves an amplifier doesn't need to be made in Arizona for Fender Corporation to designate it a Custom Shop. That position could be up for "the weakest argument of the year award" anyways. Besides, I thought we were trying to discover if any of the Prosonics were actually Custom Shop Amps? Uncover whether it's a myth or not. Everyone will see the pics soon enough.

 

Look I'm not trying to argue here. If you read what I said I said that it could be that they had a smaller Custom Shop division at the Lake Oswego factory. But that the FACT was that these amps were not build at the Custom Shop factory in Scottsdale Arizona.

 

The way I heard the STORY (not claiming it is true) is that the Prosonics were first meant to be Custom Shop produced but later it was decided that they will go to the regular production line to Lake Oswego. Where most regular Fender amps at the time were built along with some Sunn ones.

 

Ok, so here are some pictures of the later Prosonic. I can't see any differences (but that doesn't mean much since I'm not a tech so bear with me)

 

 

 

[RoboPimp]

I'd say you're right, there's no significant difference between those two chassis so who cares where or when anyone's prosonic was made

[ghbaudio]

Who cares? I do.

 

Which amp would a collector or professional want?

 

When this discussion started off we were trying to determine if there was ever a Custom Shop Prosonic. Now were discussing what constitutes a Custom Shop amp. I've listed many sources which confirm what I'm saying. You guys have nothing other than your opinion. The tube chart on my amp says "Fender Amp Custom Shop" -not designed in the Custom Shop. Catalogs from 1995-96 list the Prosonic in the Custom Shop section with the other custom amps.

 

Can you show any Fender literature from 1995-96 that says the Prosonic was regular production amp at the time? And why do the later ones have a different tube chart and faceplate? Brochures from 1997 even discussed that the Prosonic was moving to the Professional series but taking it's custom shop roots with it. Why did Fender mention this?

 

Although the last circuit you've shown is the closest to mine I've seen (the other one had more differences) both still have different tone caps (the light blue ones on the left). I've recapped a bunch of blackface and silverface amps and the tone a coupling caps have a big impact on the bandwidth and tone of the amp (even with the tone controls set at 12:00). Orange drops give amps more top end than they had stock, Mallory 150 series are warmer but hump the mid range. Every cap changes the frequency response somewhat. Why do you think many pros have their pedals & amps modified with upgraded caps, parts, etc?

 

I do believe if the caps were available through a Fender supplier they could be easily upgraded. And even if they weren't there's many high quality caps that could be used. This very well could be what players are hearing. And for the ones that don't have ceramic tube sockets - that's easy to upgrade.

 

My point all along is the early Prosonics were considered Custom Shop amps. And while some of the later ones may be close, others have more changes. Even subtle differences matter to professionals that want the best tone available. And having an amp that's rare has always effected resale value.

 

Here's a pic of a Corona tube chart.

[RoboPimp]

Who cares? I do. Which amp would a collector or professional want?

 

neither

 

get over it man, your amp isn't really anything special

[Vintage-65]

neither get over it man, your amp isn't really anything special

 

....so true its hurts a little.

[ghbaudio]

Here's the differences I see.

 

C2

C5

C11

C18

C19

C105

C106

*Different bias pots

*Custom Shop has Carling switches

*The first Professional Tube Amplifier posted has plastic tube sockets.

 

P.S. If you remove the disc cap on V1 from your amp it will give more treble and harmonics. Many people think the Prosonic is too dark (I did) and removed it from mine. Even Bruce Zinky recommends this and said he wasn't sure what he was thinking when he did it. It definitely rolls off treble.

[ghbaudio]

NOTE: DRAIN THE FILTER CAPS BEFORE WORKING INSIDE THE AMP!!!!

 

After you've drained the caps you can remove or just clip out the 5pf disc cap on v1. The amp has more sparkle now.

 

Here's a pic of the cap I'm talking about.

 

http://i271.photobucket.com/albums/jj125/ghbaudio/Disccapmodcopy.jpg

[NoirAbattoir]

 

Who cares? I do. Which amp would a collector or professional want? When this discussion started off we were trying to determine if there was ever a Custom Shop Prosonic. Now were discussing what constitutes a Custom Shop amp. I've listed many sources which confirm what I'm saying. You guys have nothing other than your opinion. The tube chart on my amp says "Fender Amp Custom Shop" -not designed in the Custom Shop. Catalogs from 1995-96 list the Prosonic in the Custom Shop section with the other custom amps. Can you show any Fender literature from 1995-96 that says the Prosonic was regular production amp at the time? And why do the later ones have a different tube chart and faceplate? Brochures from 1997 even discussed that the Prosonic was moving to the Professional series but taking it's custom shop roots with it. Why did Fender mention this? Although the last circuit you've shown is the closest to mine I've seen (the other one had more differences) both still have different tone caps (the light blue ones on the left). I've recapped a bunch of blackface and silverface amps and the tone a coupling caps have a big impact on the bandwidth and tone of the amp (even with the tone controls set at 12:00). Orange drops give amps more top end than they had stock, Mallory 150 series are warmer but hump the mid range. Every cap changes the frequency response somewhat. Why do you think many pros have their pedals & amps modified with upgraded caps, parts, etc? I do believe if the caps were available through a Fender supplier they could be easily upgraded. And even if they weren't there's many high quality caps that could be used. This very well could be what players are hearing. And for the ones that don't have ceramic tube sockets - that's easy to upgrade. My point all along is the early Prosonics were considered Custom Shop amps. And while some of the later ones may be close, others have more changes. Even subtle differences matter to professionals that want the best tone available. And having an amp that's rare has always effected resale value. Here's a pic of a Corona tube chart.

 

 

 

Changing the sticker doesn't mean much. The gut shot of your amp shows no discernable difference between the one posted by the other dude. Your certainly isnt' PTP, that's for sure. Anyhow, I don't buy into the PCB/PTP. It's all smoke and mirrors, as far as my ears can tell. Either the circuit has got the goods, or it doesn't. The Prosonic has the goods, but it needs some tube swapping to bring out the best in it.

[NoirAbattoir]

NOTE: DRAIN THE FILTER CAPS BEFORE WORKING INSIDE THE AMP!!!! After you've drained the caps you can remove or just clip out the 5pf disc cap on v1. The amp has more sparkle now. Here's a pic of the cap I'm talking about. http://i271.photobucket.com/albums/jj125/ghbaudio/Disccapmodcopy.jpg

 

Thanks for sharing that mod. I would have liked to try that one out on my prosonic when I owned it. Anyhow, I still don't see how your amp is supposed to be "custom." The things you've described as differences were don't sound like they would have changed the cost of production on the amp much.

[WorkingClassDan]

 

The Prosonic has the goods, but it needs some tube swapping to bring out the best in it.

 

 

That's what it all comes down to doesn't it.