It is currently Mon Mar 16, 2020 1:09 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 108 posts ]  Go to page 1, 2, 3, 4, 5 ... 8  Next
Go to page 1, 2, 3, 4, 5 ... 8  Next
Author Message
Post subject: 1970's Bassman 10 project just came in
Posted: Mon May 18, 2015 12:36 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Jul 17, 2007 3:08 pm
Posts: 2889
This just came in on a trade deal on some trade stuff that had been sitting around far too long !
The fella says it cuts out occasionally and swapped the RCA 6L6GC's for tung-sol reissues
Thankfully he saved the RCA's and gave them to me.
Speakers are rough at best , however dig that original cover :mrgreen:
Image

Image

Image

Pretty clean !
Looking for mods to possible turn it into a nice guitar combo or just get it running well, we shall see

_________________
Keepn' the Blues Alive

2004 50th Ann. Limited edition AMSE Stratocaster
2017 50's Baja Telecaster BSB

1968 Bandmaster with 2X12 cab C-rex speakers
VHT Special 6 Ultra combo

Visual Sound Route 66
Cmatmods Signa Drive


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Mon May 18, 2015 1:06 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Jul 17, 2007 3:08 pm
Posts: 2889
These came with it
Image

Both have close 1975 dates on them, the owner who owned it the last 17 years said he thought it was a 75
Chassis coming out soon !

_________________
Keepn' the Blues Alive

2004 50th Ann. Limited edition AMSE Stratocaster
2017 50's Baja Telecaster BSB

1968 Bandmaster with 2X12 cab C-rex speakers
VHT Special 6 Ultra combo

Visual Sound Route 66
Cmatmods Signa Drive


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Mon May 18, 2015 5:09 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
blues bondsman wrote:
...Chassis coming out soon !



:giddy:

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Mon May 18, 2015 5:17 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Jul 17, 2007 3:08 pm
Posts: 2889
Well then here ya go
Image

Image

Image

_________________
Keepn' the Blues Alive

2004 50th Ann. Limited edition AMSE Stratocaster
2017 50's Baja Telecaster BSB

1968 Bandmaster with 2X12 cab C-rex speakers
VHT Special 6 Ultra combo

Visual Sound Route 66
Cmatmods Signa Drive


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Mon May 18, 2015 5:29 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
Fantastic! It looks as clean as can be. 8)

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Mon May 18, 2015 5:50 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Jul 17, 2007 3:08 pm
Posts: 2889
A lot of static and rushing wind noise when you fire up the standby switch, looks like the first two filter caps were changed and all the 20 uf are 40 years old, I fixed one very poor solder joint so far.
Got a Glitchy component somewhere !
Whats up with the black Cap ??? didn't know they made different colors or is it a Sprague counterfeit ???

Image

Image

_________________
Keepn' the Blues Alive

2004 50th Ann. Limited edition AMSE Stratocaster
2017 50's Baja Telecaster BSB

1968 Bandmaster with 2X12 cab C-rex speakers
VHT Special 6 Ultra combo

Visual Sound Route 66
Cmatmods Signa Drive


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Mon May 18, 2015 8:21 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
Is it an F&T?

Rushing wind noise could be preamp tube(s).

It looks like those RCA have been run very hot, or are just about shot. :idea:

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Mon May 18, 2015 8:39 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Jul 17, 2007 3:08 pm
Posts: 2889
The Black cap says Sprague on it ??? weird !
The RCA 6L6GC test strong so ???
The master volume has probably been parked on ten forever, a good shot of deoxit and the power all returned and it is whisper quiet now at idle.

Just guessing I'll need to replace or bypass the master volume at some point.
The speakers are rough at best, however somehow still sound great at lower to mid volumes

Image

The label has no date code
Image

Silver twins 8)
Image

_________________
Keepn' the Blues Alive

2004 50th Ann. Limited edition AMSE Stratocaster
2017 50's Baja Telecaster BSB

1968 Bandmaster with 2X12 cab C-rex speakers
VHT Special 6 Ultra combo

Visual Sound Route 66
Cmatmods Signa Drive


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Mon May 18, 2015 11:20 pm
Offline
Rock Star
Rock Star
User avatar

Joined: Sat Jul 03, 2010 2:18 pm
Posts: 6544
" The Black cap says Sprague on it ??? weird ! "

Chris, I believe that cap is a Sprague. The era when Sprague went to black caps with green lettering on most cap (1980s) --- some of the larger mfd cap had white lettering on black. So... that cap is 30 years old.

In the early 1990s --- Sprague kept black with green for lower mfd valued caps. And went to the blue with black lettered types, on bigger mfd caps.


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Tue May 19, 2015 4:23 am
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Jul 17, 2007 3:08 pm
Posts: 2889
Thanks Beemer !
Now its running super quiet (cant hardly hear it run at idle) and despite the speakers with some kind of silicone on them and one with a hole on the surround, the amp sounds very good !
obviously it breaks up pretty fast and gets overly gritty past 4 on the volume.
I do believe a gunked up master volume was its only real problem (besides speaker issues).

It will get a electrolytic cap job soon any way :mrgreen: those mallory's are 40 years old !

_________________
Keepn' the Blues Alive

2004 50th Ann. Limited edition AMSE Stratocaster
2017 50's Baja Telecaster BSB

1968 Bandmaster with 2X12 cab C-rex speakers
VHT Special 6 Ultra combo

Visual Sound Route 66
Cmatmods Signa Drive


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Tue May 19, 2015 1:42 pm
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Jul 17, 2007 3:08 pm
Posts: 2889
I pulled the worst of the four speakers and found codes for possible recone

137 7506
010134

CTS 6th week of 1975

_________________
Keepn' the Blues Alive

2004 50th Ann. Limited edition AMSE Stratocaster
2017 50's Baja Telecaster BSB

1968 Bandmaster with 2X12 cab C-rex speakers
VHT Special 6 Ultra combo

Visual Sound Route 66
Cmatmods Signa Drive


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Tue May 19, 2015 4:04 pm
Offline
Rock Star
Rock Star
User avatar

Joined: Tue Mar 01, 2011 3:10 pm
Posts: 5646
Location: Gateway to the West
The guts "Look" very similar to my Bantam Bass Amps. I wonder how close these circuits really are?

Cool that you got a good testing set of RCA bottles...quite the score!

Looks like a easy project for ya! Enjoy.

T2

_________________
-----------------------------------------------------------
What time is it? It's Fender Time.


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Wed May 20, 2015 3:34 am
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Jul 17, 2007 3:08 pm
Posts: 2889
I was glad the RCA's are holding up too !
It is a very simple circuit for sure and again other than the fully sealed cab that holds back the full range of guitar sound a bit, it has a nice tone.

Off topic but i found a fun craigslist find yesterday
sorta old meets new, the cabinet is 1950's the speakers are webers alnico signature series
Image

Image

Image

They say Knight Allied Radio Corporation Chicago IL on the front
Sweet honking sound through my little VHT head, my guess is that a Harp player in small clubs would sound killer through them 8)

_________________
Keepn' the Blues Alive

2004 50th Ann. Limited edition AMSE Stratocaster
2017 50's Baja Telecaster BSB

1968 Bandmaster with 2X12 cab C-rex speakers
VHT Special 6 Ultra combo

Visual Sound Route 66
Cmatmods Signa Drive


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Wed May 20, 2015 6:26 am
Offline
Professional Musician
Professional Musician
User avatar

Joined: Tue Jul 17, 2007 3:08 pm
Posts: 2889
Tone update
I pulled the Tung-sol Reissue 6L6GC STR power tubes and put those RCA's in that the owner said a tech told him were bad ???? ((( NOT ))) !!!
pulled the two jj 12AX7's and installed a Raytheon 5751 in v-1 and a real RCA 7025 in V-2

Night and day !!! man NOS tubes are the ticket !

also ordered one of these till I weber can hopefully do their magic on the old speakers
http://www.ebay.com/itm/Jensen-MOD10-50 ... 1e9f03066c
The guys at weber said they had 32ohm coils, however they only fit certain makes of speaker so....... I might be stuck with Jensen wannabees :roll:

The tone right now with the one REAL Bad speaker is pretty sweet !
I wonder if the bad rap comes from the 70 watt ultra linear models that came two years later than mine ?
although there are a few U/L guys who love theirs too.

This might be the very best cost to tone ratio amp ever !!! 8)

_________________
Keepn' the Blues Alive

2004 50th Ann. Limited edition AMSE Stratocaster
2017 50's Baja Telecaster BSB

1968 Bandmaster with 2X12 cab C-rex speakers
VHT Special 6 Ultra combo

Visual Sound Route 66
Cmatmods Signa Drive


Top
Profile
Post subject: Re: 1970's Bassman 10 project just came in
Posted: Wed May 20, 2015 7:36 am
Offline
Rock Star
Rock Star
User avatar

Joined: Sat Jul 03, 2010 2:18 pm
Posts: 6544
Interesting circuit. What does the STUDIO input do that the NORMAL doesn't? In terms of 6L6GCs --- there will be no current models that come close to NOS RCA or GEs. Tone-wise or longevity. But, you knew that... :D


http://www.ampwares.com/schematics/bassman_10.pdf


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 108 posts ]  Go to page 1, 2, 3, 4, 5 ... 8  Next
Go to page 1, 2, 3, 4, 5 ... 8  Next

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: