Results 1 to 9 of 9

Thread: Help! My Gretsch 1965 6162 Amp Sounds Anemic. Help!!

  1. #1
    Member
    Join Date
    Apr 2011
    Posts
    232
    Thumbs Up/Down
    Received: 11/0
    Given: 19/0
    Rep Power
    10

    Help! My Gretsch 1965 6162 Amp Sounds Anemic. Help!!

    Help. I need recommendations on how to bring anemic sounding Valcos back to life.

    Hello everyone,

    Admittedly, I'm a valco amp junky and just can't help myself from buying these old amps online. Unfortunately, there are times when one of these beauties arrives, I plug it in, dime it and sadly my excitement turns to disappointment when all I get is an anemic clean tone when I was expecting a roar. Such was the case with a Gretsch 6162 I recently got from the west coast. I played a 6162 before that roared but this one definitely doesn't. Not to mention, I have a couple more Valcos in my collection that should roar but don't. This being the case, I set myself out on a mission on how to bring these back to life. So here I am praying that the collective experience of this forum can help me trouble shoot this anemic amp and replace what ever needs replacing to bring it's former glory.

    I did do a bit of homework before posting and from what I've read on this forum (as well as other's) I found the following:

    1) Check/replace the ground reference caps coming off the preamp plates (this was Leon's advice). Many valcos use the brown paper variety but mine has the dark red (polyester??) ones in place. Question: would these dark red ones be as prone to fail as the brown paper ones??

    2) Check/replace the white 35uf mallory electrolytic cathode bypass caps. Now where does one get 35uf caps these days??

    3) Check OT. What are the chances of a bad OT in these anemic valcos? Saying that, I know I've had at least 2 Supros with mismatched OTs. A 1961 1624T with a replaced OT specced for an 8ohm speaker hooked up to a stock 4ohm rola
    The other was a 59 Coronado with a replaced OT spec'd out for a 3 speaker layout (like a 6161). I replaced that one with a Thunderbolt OT and a fresh Celestion G30H. Now that amp just screams.

    4) Check Tubes: Easy enough but for a 6EU7 with is hard/expensive to find. I've read that rewiring that socket to take a 12ax7 is easy to do.

    5) Check Speakers: easy enough to do.

    Now can anybody here add to this. What would be the logical trouble shooting approach to finding the problem with an anemic sounding 6162.

    Schematic link (mine is the single channel version):

    http://www.guitaramplifierblueprinti...es/6162sch.gif

    Here is a link to some pictures of my anemic 6162.

    https://www.dropbox.com/sh/yv7xsmkuc...rpMjjzTVE-OiHa

    Any comments would be appreciated. Thanks

    Joseph

    0 Not allowed! Not allowed!

  2. #2
    Junior Member
    Join Date
    Feb 2010
    Posts
    11
    Thumbs Up/Down
    Received: 0/0
    Given: 0/0
    Rep Power
    0
    The first thing I would do, especially for an anemic amp, is to replace the filter caps. The orange Mallory dates to 1968 ......over 45 years old. Also replace the multi-section can capacitor. You'll want higher voltage caps due to the higher wall voltage we have today. Lots of vendors will have these....AEC, Mojo, Triode, etc. The power supply has to be working properly for everything else in the amp to do their jobs. Other than tubes, filter caps are the most likely culprit. Do this before you start messing around with coupling caps, transformers, etc.

    0 Not allowed! Not allowed!

  3. #3
    Old Timer
    Join Date
    Jun 2007
    Posts
    5,129
    Thumbs Up/Down
    Received: 108/0
    Given: 66/0
    Rep Power
    19
    Pardon my ignorance here, but are you describing a loss of volume/power or a loss of tone/frequency response?

    0 Not allowed! Not allowed!

  4. #4
    "Thermionic Apocalypse" -JT nickb's Avatar
    Join Date
    Dec 2009
    Location
    Devon, UK
    Posts
    3,813
    Thumbs Up/Down
    Received: 944/1
    Given: 693/1
    Rep Power
    14
    The schematic doesn't seem to match the images. For example I see 6EU7 in the power amp section whilst the schematic has 12AX7.

    BTW you can buy tube adapters off eBay. They have a little PCB inside with the pins that is wired to the socket terminal to suit. I think they come prewired for a 6CG7 but I think you should be able to pull them apart and rewire.

    0 Not allowed! Not allowed!
    Experience is something you get, just after you really needed it.

  5. #5
    Old Timer oc disorder's Avatar
    Join Date
    Jul 2006
    Location
    Land Down Under
    Posts
    1,268
    Thumbs Up/Down
    Received: 4/1
    Given: 1/0
    Rep Power
    15
    Hi Cluster
    Looks like you've got a good restoration project there.
    Down here in the land of the kangaroo we don't see to many of these "American bargain bin" amps although
    we had our own variation with Goldentone, Moody & Maton etc.

    See here
    http://www.ozvalveamps.org/
    Australian and New Zealand valve amplifiers for guitar and P.A. c1930's - 1970's.


    Regarding your query about 35uF capacitors 33uF is acceptable although
    if money is no object Mouser seems to have Vishay / Sprague (formally Philips as I understand)
    capacitors of that value. (The Australian prices are shown.)

    Mouser Part #: 75-TE1306-E3
    Manufacturer Part #: TE1306-E3
    Manufacturer: Vishay / Sprague
    Description: Aluminum Electrolytic Capacitors - Leaded 50V 35uF
    Pricing (AUD) 1:$4.91

    OR (below is not stocked not sure why they list it...?)

    Mouser Part #: 598-NLW35-50-PB
    Manufacturer Part #: NLW35-50-PB
    Manufacturer: Cornell Dubilier
    Description: Aluminum Electrolytic Capacitors - Leaded 35UF 50V
    Pricing (AUD) 1: $6.39 (Non stocked)

    Something like this should be fine

    ELNA-74413 33uF / 50VDC, ROA Series, 10mmD x 12.5mmL, Each $1.50 pcX USD Price

    (And 52Bill to me "anemic" means both !)

    This MEF link may be of interest

    http://music-electronics-forum.com/t15379/

    Had a quick look at your photos and couldn't help noticing where 2 of the half watt resistors had been replaced
    and am going to suggest you check all the values in the HT circuit.
    Its possible something might be starved of power !

    Attaching the schematic with circled values to check.

    Click image for larger version. 

Name:	6162schBIG.jpg 
Views:	4342 
Size:	136.9 KB 
ID:	29420

    0 Not allowed! Not allowed!

  6. #6
    Member
    Join Date
    Apr 2011
    Posts
    232
    Thumbs Up/Down
    Received: 11/0
    Given: 19/0
    Rep Power
    10
    Quote Originally Posted by 52 Bill View Post
    Pardon my ignorance here, but are you describing a loss of volume/power or a loss of tone/frequency response?
    Sorry for the confusion. I meant volume/gain loss. Not tone.

    0 Not allowed! Not allowed!

  7. #7
    Member
    Join Date
    Apr 2011
    Posts
    232
    Thumbs Up/Down
    Received: 11/0
    Given: 19/0
    Rep Power
    10
    Quote Originally Posted by nickb View Post
    The schematic doesn't seem to match the images. For example I see 6EU7 in the power amp section whilst the schematic has 12AX7.

    BTW you can buy tube adapters off eBay. They have a little PCB inside with the pins that is wired to the socket terminal to suit. I think they come prewired for a 6CG7 but I think you should be able to pull them apart and rewire.
    thanks. yes the schematic shows a 2 channel 6162 with a 12ax7 pi. mine is a one channel with a 6EU7. everything else is the same. i couldn't find the exact schematic.

    0 Not allowed! Not allowed!
    Last edited by cluster; 06-26-2014 at 10:42 PM. Reason: error

  8. #8
    Member
    Join Date
    Apr 2011
    Posts
    232
    Thumbs Up/Down
    Received: 11/0
    Given: 19/0
    Rep Power
    10
    Quote Originally Posted by 66tele View Post
    The first thing I would do, especially for an anemic amp, is to replace the filter caps. The orange Mallory dates to 1968 ......over 45 years old. Also replace the multi-section can capacitor. You'll want higher voltage caps due to the higher wall voltage we have today. Lots of vendors will have these....AEC, Mojo, Triode, etc. The power supply has to be working properly for everything else in the amp to do their jobs. Other than tubes, filter caps are the most likely culprit. Do this before you start messing around with coupling caps, transformers, etc.
    Yes. I also heard (from Leon) that those dark red/brown caps off the preamp plates should be changed too. Apparently, they go bad easy.

    0 Not allowed! Not allowed!

  9. #9
    Member
    Join Date
    Apr 2011
    Posts
    232
    Thumbs Up/Down
    Received: 11/0
    Given: 19/0
    Rep Power
    10
    Quote Originally Posted by oc disorder View Post
    Hi Cluster
    Looks like you've got a good restoration project there.
    Down here in the land of the kangaroo we don't see to many of these "American bargain bin" amps although
    we had our own variation with Goldentone, Moody & Maton etc.

    See here
    Classic ANZ Valve Guitar Amplifiers
    Australian and New Zealand valve amplifiers for guitar and P.A. c1930's - 1970's.


    Regarding your query about 35uF capacitors 33uF is acceptable although
    if money is no object Mouser seems to have Vishay / Sprague (formally Philips as I understand)
    capacitors of that value. (The Australian prices are shown.)

    Mouser Part #: 75-TE1306-E3
    Manufacturer Part #: TE1306-E3
    Manufacturer: Vishay / Sprague
    Description: Aluminum Electrolytic Capacitors - Leaded 50V 35uF
    Pricing (AUD) 1:$4.91

    OR (below is not stocked not sure why they list it...?)

    Mouser Part #: 598-NLW35-50-PB
    Manufacturer Part #: NLW35-50-PB
    Manufacturer: Cornell Dubilier
    Description: Aluminum Electrolytic Capacitors - Leaded 35UF 50V
    Pricing (AUD) 1: $6.39 (Non stocked)

    Something like this should be fine

    ELNA-74413 33uF / 50VDC, ROA Series, 10mmD x 12.5mmL, Each $1.50 pcX USD Price

    (And 52Bill to me "anemic" means both !)

    This MEF link may be of interest

    http://music-electronics-forum.com/t15379/

    Had a quick look at your photos and couldn't help noticing where 2 of the half watt resistors had been replaced
    and am going to suggest you check all the values in the HT circuit.
    Its possible something might be starved of power !

    Attaching the schematic with circled values to check.

    Click image for larger version. 

Name:	6162schBIG.jpg 
Views:	4342 
Size:	136.9 KB 
ID:	29420
    Wow. Thanks for that great info. Will source those parts you mentioned.

    0 Not allowed! Not allowed!

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Gretsch compact reverb tremolo amp
    By Mr Johnny Birchwood in forum Schematic Requests
    Replies: 2
    Last Post: 12-23-2012, 03:57 AM
  2. Help with 1965 Vox solid state amp, please!
    By AmpRX in forum Maintenance, Troubleshooting & Repair
    Replies: 10
    Last Post: 07-07-2011, 12:26 AM
  3. Gretsch playboy amp vibrato problem
    By lordhoho in forum Maintenance, Troubleshooting & Repair
    Replies: 6
    Last Post: 08-01-2008, 12:21 PM
  4. 1965 SUNN Amp?
    By Jenkster in forum SUNN
    Replies: 8
    Last Post: 02-14-2008, 04:34 AM
  5. Gretsch amp static heard during peaks
    By cjlectronics in forum Maintenance, Troubleshooting & Repair
    Replies: 4
    Last Post: 06-23-2006, 06:16 PM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •