AMPEG'S current method to prevent servicing SVT-CL's

[nevetslab]

How to prevent servicing new amps? Pour both Threadlock into all hardware that would have to be removed, then add red Glyptol over the nut/threads. Don't bother tightening the hardware. Only use latching 1/4" Fast-On Female connectors so you can't remove them...for certain on the power and standby switches! Pour RTV over everything, particularly those leads you need for clipping your ground clip of your DMM onto. Only use non-hardened soft-steel Chinese cage nuts that both break and pop out of the chassis when putting them back together. Use random-sized 2mm Hex drive truss head screws threaded into non-tightened power tube PCB mating standoffs to mount the tube sockets, so only half of the screws can be removed, others either strip out immediately, won't even acknowledge your undamaged end 2mm hex driver, and the rest just spin the hex standoff of the power tube PCB so you can't remove the cover plate.

Took me 20 minutes just to remove the stinking preamp chassis from their current production antics. I can't wait to get to the second power tube PCB/cover plate.

[g1]

Sounds like the manufacturing end got some recommendations from the servicing/warranty end and didn't bother to discuss how to implement possible solutions.

[J M Fahey]

Remember that is not an Ampeg but a Crate/Sanyo amplifier designed for 100V mains ONLY.

[The Dude]

As "luck" would have it, I just cracked open an SVT-VR. Same shit. Transformers bouncing around, screws rolling around in the chassis, broken cage nuts, threadlock, glyptol, etc., etc.

I'll tell ya what really gets my goat, though. They have thread lock and red glyptol all over the screws you remove to gain access to the transformer screws (circuit board mounting, etc.). BUT, NOT A DROP OF ANYTHING ON THE TRANSFORMER SCREWS? WTF?

[glebert]

Man, $2k doesn't get you much for a bass amp these days, I guess...

[The Dude]

Well, the parts are all there. The hitch is that the amps are poorly assembled. Think of the modern SVT as an "Ampeg Amp Kit- some assembly required".

[Justin Thomas]

Sure it does.

https://reverb.com/item/6594351-ampe...d-1970-s-black

The best there is, the best there was, the best tgere ever will be.

Jusrin

[nevetslab]

Well, the parts are all there. The hitch is that the amps are poorly assembled. Think of the modern SVT as an "Ampeg Amp Kit- some assembly required".

That's why some of my clients who rent this stuff out are now sending them over to me first before letting them out the door on rental. While knowing how to deal with all these, and put them back into proper condition, it still riles the dickens out of me to see that going on. I'm assuming these new ones are now coming from Yamaha? I guess it must just be in name, while still being assembled in the same factory(s)? At least once back in order, they're still a monsterously good amp!

[DrGonz78]

It's such a pleasure working on the old SVT amps. The ones built like a tank!! Have not had the displeasure of working on a modern one yet. Thanks for all the forewarning and tech tips though.

[glebert]

Man, $2k doesn't get you much for a bass amp these days, I guess...

To be fair, my main amp is an Ashdown class D which sold for $800 new and the BOM cost on that is less than the tubes alone on any of the heavy iron SVTs. Also, the SVTs are actually cheap relative to when they first came out. The list price in '69 for an SVT was $1450, which is $10,000 in today's dollars. I guess this included two 810 cabinets, so a new rig today with head two of the good 810s would be about $5000, I think.

[nevetslab]

I guess I tend to grumble a bit when two new amps that need to be set up properly so they won't self-destruct show up, and stop you at every step along the way of the tear-down. The power and output transformers in the SVT-CL, -AV & -VR arrive out of the box with their mounting hardware loose. As is the five power amp mounting screws, which will fall out on the first tour. To get at three of the eight screws of the P/T & O/T, you have to gut it completely, and lift the power amp PCB up and out, as that board hides the remaining screws. All part of the drill.

I will say in their favor, is they have finally changed the 1W 1N4744 15V zener diodes that run the bipolar 15V supplies to 5W zeners (didn't mark down the p/n), and the 220 ohm screen resistors that I've been changing to 1W MO, now there are 220 ohm 2W MO resistors in place. About time!

I don't get to see many of the original/vintage SVT's here. We have one SVT II, predecessor to the SVT2-Pro. I had used one of the original SVT's with two 810 cabs jamming with some folks up in Topanga Canyon back in '70, and that was an awsome amp rig!

[Jazz P Bass]

Have you tried contacting Ampeg?

Not that you are the only one experiencing these issues, but.

They may take the feedback to heart.

Then again...........

[drewl]

Wait, you're saying they come without transformers installed?

[glebert]

Have you tried contacting Ampeg?

Not that you are the only one experiencing these issues, but.

They may take the feedback to heart.

Then again...........

I think a bunch of warranty repairs for these issues would get their attention.

[nevetslab]

Have you tried contacting Ampeg?

Not that you are the only one experiencing these issues, but.

They may take the feedback to heart.

Then again...........

Actually, I haven't spoken with anyone since 2011 or maybe 2012...Loud Technology. You're right....they should have the views of those who have to service these after they come back off tours, riding the trucks in road cases. And for sure, with their current manufacturing methods that in some cases, are enough to throw your hands up in disgust, wanting to quit on it, though my pride won't let me.

Though, putting the main PCB back into the chassis, and after having to grovel on the floor again after the ice cream lid full of the hardware to remount that big board was recovered....the two long black thread-cutting screws that came OUT of the XLR Male connector...absolutely DO NOT want to thread back in. WTF????!! It's plastic inhibiting a steel screw?!! I had the same problem with the other one yesterday.

Ampeg also eliminated the right angle Fast-on connectors of the Heater Wires, where they had always plugged onto the bottom of the power tube PCB, and all too often, oxidation build-up on the crimp connections generate so much heat, the plastic sleeves over the right angle connector would blacken, then you'd loose heater voltage all together. Those are now directly soldered into the PCB. With large blobs of solder on the top side of the PCB's solder pads. Of course they eliminated the service loop on that jacketed paired wires, so getting those off the board for further disassembly is thrilling work.

I wonder if you have to contact Yamaha to get to who is in charge of customer service / production engineering to address all their faults. Heaven forbid they correct all the ills found from shoddy production. I make a lot of money on these amps due to that.

Ah, and of course, they DO come with the transformers installed. You just have to compete their manufacturing efforts.....full teardown to get at all of the mtg screws req'd.

AS for Warranty repairs, based on setting these amp up so they're survive tours, that would be an interesting challenge. This weeks venture is both Preventative Maintenance and minor modification to make them more serviceable (removing the garden hose sleeving for Tech Flex used on the two preamp harness bundles), and adding lock washers strategically.