Amp Guts Photos - Official Thread - Lets see those pics

[BassmanPaul]

Wow... When these were in production, I asked Sunn for a schematic, which they provided. I also priced transformers since I was a poor teenager and considered building one. See this, I totally could have done it!

Have you ever successfully built a tube amplifier? LOL

 

[SherpaKahn]

Original warranty envelope still stuck inside 1970 SVT


View attachment 3977596

I bet this amp kicks out a wonderful aroma.

 

[bobyoung53]

I bet this amp kicks out a wonderful aroma.

It does and it kicks up a wonderful sound too. I've played it a few times and it didn't hum but I'm going to recap it anyway, it sounds different than most SVTs to me, it's a screamer. I've been out of the country since November though so haven't been able to touch it but hopefully will be able to finish it in a few months, I got the cap kit back at home already.

 

[BillyB_from_LZ]

Have you ever successfully built a tube amplifier? LOL

Never built one from scratch. Messed around with the insides of a bunch of them though.

 

[SherpaKahn]

It does and it kicks up a wonderful sound too. I've played it a few times and it didn't hum but I'm going to recap it anyway, it sounds different than most SVTs to me, it's a screamer. I've been out of the country since November though so haven't been able to touch it but hopefully will be able to finish it in a few months, I got the cap kit back at home already.

So so so glad to hear about the recap idea: The museum-goer in my appreciated seeing them in that picture, but the rest of me saw a timebomb. It's anecdotally impressive how long some of these old electrolytics can sometimes last: My B18N still has the original caps, but the replacements and mounting clamps are here waiting to be installed. Also, an SVT is probably 3rd from the top of my list of amps I'd not want to take down the "still on the original capacitors" adventure, let alone one with properly-awesome top-cap tubes.

It will be difficult to find new-manufacture replacement capacitors as large as the originals: New caps will generally be smaller, and the "radial" form has more product diversity You can likely clamp them in the same way it's done in Hiwatt amps. If the rest of the specs are good, go for 105-degree rated caps with the longest lifespan and lowest ESR. @beans-on-toast may know some good ones: I'm irrationally fond of Link Removed caps, which are available in a variety of ratings.

 

[bobyoung53]

So so so glad to hear about the recap idea: The museum-goer in my appreciated seeing them in that picture, but the rest of me saw a timebomb. It's anecdotally impressive how long some of these old electrolytics can sometimes last: My B18N still has the original caps, but the replacements and mounting clamps are here waiting to be installed. Also, an SVT is probably 3rd from the top of my list of amps I'd not want to take down the "still on the original capacitors" adventure, let alone one with properly-awesome top-cap tubes.

It will be difficult to find new-manufacture replacement capacitors as large as the originals: New caps will generally be smaller, and the "radial" form has more product diversity You can likely clamp them in the same way it's done in Hiwatt amps. If the rest of the specs are good, go for 105-degree rated caps with the longest lifespan and lowest ESR. @beans-on-toast may know some good ones: I'm irrationally fond of Link Removed caps, which are available in a variety of ratings.

I bought a cap kit at Fliptops.com, hopefully it will be composed of good caps. I want to get that thing running good and safe, it sounds great.

 

[beans-on-toast]

I'm irrationally fond of Link Removed caps, which are available in a variety of ratings.

Modern caps are way better than the original ones. I do circuit boards so I can use modern snap in ones.

 

[SherpaKahn]

Modern caps are way better than the original ones. I do circuit boards so I can use modern snap in ones.

I was thinking in the other direction, of hollow round heavy paper-colored heatsinks stuffed with teeny modern caps. Kinda like the repro Spragues, but actually useful.

Boards are handy indeed, but for now I just use one clamp per cap; I stocked a small variety of vertical & horizontal options with 2 & 3-hole mounting. I may cut up some insulating board to make a washer for stacked supplies with the case floating at a voltage. Then insulating tape between clamp and can walls.

 

[agedhorse]

There is no comparison between modern caps and many of the older cap styles. The operating capabilities are much better overall and their lifespan at elevated temperatures and ripple currents are so much better.

That said, probably 90-95% of all caps changed have PLENTY of life remaining... and close to the same can be said of tubes. I also see a fair amount of damage cause by recap attempts, especially with hacks working on PCB amps. The number and magnitude of mistakes made when "fixing problems that really didn't exist" are remarkably high too.

Just my experience from working on thousands of amps over the years.

 

[12bass]

There is no comparison between modern caps and many of the older cap styles. The operating capabilities are much better overall and their lifespan at elevated temperatures and ripple currents are so much better.

That said, probably 90-95% of all caps changed have PLENTY of life remaining... and close to the same can be said of tubes. I also see a fair amount of damage cause by recap attempts, especially with hacks working on PCB amps. The number and magnitude of mistakes made when "fixing problems that really didn't exist" are remarkably high too.

Just my experience from working on thousands of amps over the years.

Dunno much about MI amps, but I have an NAD 3020 here from the early 80s that definitely needs the electroytics replaced; it sounds super thin with barely any signal transfer through the circuit. Used my capacitance meter on a friend's previous 3020 and over 90% of the electroytics were way below spec (practically every electrolytic capacitor tested was bad). Sounded great with the new caps!

 

[agedhorse]

Perhaps they used a poorer quality cap than they thought.

I have plenty of examples of amps and even consoles with caps that are pretty much close to that old without a single problem. Even after >10k hours, not a problem. I am looking at my shop's test amp that has been running 24/7 for about 8 years now... something like >50k hours and it is plenty fine too.

 

[StereoPlayer]

Probably already posted...GK MB-200
Painted the top, took pics while apart.

 

[BassmanPaul]

Never built one from scratch. Messed around with the insides of a bunch of them though.

Building one from scratch is completely different than messing about inside a ready built unit.

 

[Frankie Fender]

Who likes to see the inside of amps? I usually take pictures of amps that I have owned to reference the tube positions, etc. and generally because I am curious as to what's inside. Here is a sample of some of my amps in the past. Please post yours if you got 'em!

Mesa D-180

Aguilar DB750

GK Fusion 550

Ampeg SVT (1970s)

Ampeg SVT-II

Mesa Walkabout

Mesa WD-800

Traynor YBA 100

 

[Passinwind]

Who likes to see the inside of amps? I usually take pictures of amps that I have owned to reference the tube positions, etc. and generally because I am curious as to what's inside. Here is a sample of some of my amps in the past. Please post yours if you got 'em!

Ahem: Amp Guts Photos - Official Thread - Lets see those pics

 

[Frankie Fender]

Ahem: Amp Guts Photos - Official Thread - Lets see those pics

Thanks. Evidently everything on TB has already been covered I am discovering.

 

[beans-on-toast]

Thanks. Evidently everything on TB has already been covered I am discovering.

Every song that’s been written has it’s origin somewhere else.

 

[S-Bigbottom]

Thanks. Evidently everything on TB has already been covered I am discovering.

Yup.
Now go grab a rag or four, click on that link and we will see you in a month.

 

[OldogNewTrick]

Don't forget to ask a mod to move your post to the right thread, which has been our collective source of drool worthy pics

 

[coreyfyfe]

Picked up this Verellen model T clone recently. Had a bit of a bumpy ride with fedex, as evidenced by the PT, but everything is running smoothly.