Super reverb conversion question

[Toxophilite]

There's a late 70s master volume(pull pot) super reverb for sale locally for comparatively cheap(it's supposedly had the normal channel modded a litle but is otherwise intact).Not much more than the $325 I paid for mine in about 1988 when it was 8 years old (I Brought it home on a bus!). I've really liked my amp, it's been a brick,  very nice sounding and it's been dragged all over both our countries and played 1000 or so shows over the years not including rehearsals recording etc.
However it is very large and heavy.

I had an idea of buying this one, maybe putting it in  a shorter cab with 2 - 10" 8ohm speakers and perhaps even converting  it to something more on the order of an older super powerwise by putting in a different non-linear OPT. I have one from a Baldwin organ that used 2 6L6GT. Perhaps ending up with a smaller, lighter and less powerful 'super'
I would save it's older cab and OPT in case I ever wanted to convert it back

Is this crazy talk??  How much more work would need to be done besides just replacing the OPT.   I'm not fussy about the blkface vs silverface . I think they're both great sounding amps so i don't need to do a full blkface conversion, just bring the power back a little and maybe save a few lbs.

Thanks

[Ed_Chambley]

There's a late 70s master volume(pull pot) super reverb for sale locally for comparatively cheap(it's supposedly had the normal channel modded a litle but is otherwise intact).Not much more than the $325 I paid for mine in about 1988 when it was 8 years old (I Brought it home on a bus!). I've really liked my amp, it's been a brick,  very nice sounding and it's been dragged all over both our countries and played 1000 or so shows over the years not including rehearsals recording etc.
However it is very large and heavy.

I had an idea of buying this one, maybe putting it in  a shorter cab with 2 - 10" 8ohm speakers and perhaps even converting  it to something more on the order of an older super powerwise by putting in a different non-linear OPT. I have one from a Baldwin organ that used 2 6L6GT. Perhaps ending up with a smaller, lighter and less powerful 'super'
I would save it's older cab and OPT in case I ever wanted to convert it back

Is this crazy talk??  How much more work would need to be done besides just replacing the OPT.   I'm not fussy about the blkface vs silverface . I think they're both great sounding amps so i don't need to do a full blkface conversion, just bring the power back a little and maybe save a few lbs.

Thanks

Not crazy at all.  I don't know if you will get less power.  I did one a while back.  it was a 77 Super beat up.  I simply put it into a Mojo 2 10 cab and used a Bassman OT at 4 ohms.  Used 2 8 ohm 10's.

Take a look at the 63 Viborverb.  I have built a few of these for guys doing the same thing.  I just would change the circuit enough to have adjustable Fixed Bias replacing the balance.

I also like to use the normal channel using JCM 800 values and add a mid pot.  This works well with the 12Ax7 PI of the Vibroverb circuit.  They are quieter with 2 10's, but I used Celestion Gold 10 in the 3 I built and it is as loud as my Super Reverb is.

Lots of things you can do if you get it for the right price.

On second thought, It might be crazy.  If you saw all the parts I have horded over the years you would thing crazy.

[Toxophilite]

Cool
Thanks for that . I've made an offer I can afford and we'll se what happens


A question if I may about late 70s super reverbs and impedance when using the extra speaker output


My 1980 super (silver face 70 watt ultralinear etc ect) has 4  16 ohm speakers with a 4 ohm load which is what it's rated at for the OT
It also has an extra speaker output next to the normal one also listed at 4 ohms
i've always runa small portable 4 ohm leslie unit out of this output
I put a new 4 ohm speaker in the leslie unit and it seems to be bogging down my amp some


How does this speaker out work
Does it actually change the load on the OPT?

[eleventeen]

The (USED) parts cost for building a Super Reverb is in the neighborhood of $500, eg; trannies: $100 tubes; $50 sockets & pots & R's & C's = $100. Speakers = $100. Cabinet $100. Chassis $50. That's a silly price, go get it. Especially if you can build your own (versus buying) cut-down cabinet, this is a no brainer.

[Toxophilite]

Well I picked up that super, and it was good deal nice sounding amp
As my old super had a 4 ohm impedance it might be easier top build a new 2 x 10 or 12 cabinet for it as I have some 8 ohm speakers and 4 ohm ones seem to be not as common (also it's cabinet is beat!)


I had a question
My old (super) 1980 seems to be a lot less warm sounding than the new (1978) one though they're both the same fender configuration.
The 1980 is quite bright with less bottom at the same point on the bass knob while the 1978 has fuller bass but less top at the same point, Quite a noticeable difference


I did recently redo the Electrolytics in the power supply of the 1980 as well as all the 100 waatt resistors going to the plates and a few other small things. Other than that it's stock, oh and it has had the push pull switch removed as it had broken and i installed a new pot.


Could this be a speaker thing?
drifted component values??

[Toxophilite]

Opening the two up to compare they seem identical (except for the new components in the 1980)
THey both use the green OPT tap with the built in speakers and when the EXT jack is used it switches both signals to the green and yellow OPT tap
one would assume that on the 1980 (4 ohms load) that this would switch to 2ohms
and with the 1978 (2 ohm)this would switch to 1 ohm load


The 1978 has a replaced elecotrolytic in the cap barn and a sandbox 500 ohm cap on one of the power tube sockets which shows a bit of scorch beside it...ooopsy! (not me)


other than that and the lack of pushpull master volume they seem to be identical


I did find this cute label under the reverb tank of the 1978