It looks like you're new here. If you want to get involved, click one of these buttons!
Subscribe to our Patreon, and get image uploads with no ads on the site!
I took delivery of a used TT50 head yesterday, the second one I've owned and having had the combo too. I have a real soft spot for these amps and love their tone and flexibility.
The amp arrived working mostly fine, but with the reverb totally dead. It has a master reverb control and then separate dials on the three channels, all fed from an Accutronics spring tank. I had the chassis out last night to see if any wires had come loose during transit, and all were fit nice and snug.
I've tried replacing what I am lead to believe is the 12AX7 responsible for the reverb circuit, but it isn't making a difference. What is next to try? I can harvest an Accutronics reverb tank from my H&K Tube 50 combo to try, but does it have to be the exact same type etc?
The amp is a clean example, from a decent private seller (300 miles away of course) and I'd like to try and get the issue fixed locally as inexpensively as possible if a DIY solution is available, having already paid slightly over the eBay going rate for a clean, well looked after example.
The seller tells me the reverb was working fine on testing before boxing the amp up, and he did package it well.
Any advice you knowledgeable chaps can offer will be most gratefully received...
Schematic here - http://www.tremolo.pl/Firmowe/LANEY/TT50H.pdf
Manual here - http://www.audiotek.sk/produktyGTA/laney/laney_tt50600px_p1.pdf
Base theme by DesignModo & ported to Powered by Vanilla by Chris Ireland, modified by the "theFB" team.
Comments
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
@jpfamps @crunchman & @ICBM thanks for taking the time to help me out with this.
I stripped the amp down last night and followed all your suggestions, apart from @jpfamps multmeter idea as I don't have one. My self-diagnosis is that the tank is dead as it didn't respond to any of the suggestions @ICBM offered. To my untrained eye there doesn't look to be anything physically wrong with the tank, but I guess there must be.
Moving on to the question of sourcing a replacement tank while I have the amp in bits, while the model number remains the same (4BB3C1B), the colour and look of the current tank available are different:-
http://i1085.photobucket.com/albums/j437/stefbillington/Misc/WV_zps62b24581.jpg
Watford Valves have these in stock for a reasonable £22.50 + P&P - http://www.watfordvalves.com/product_detail.asp?id=1253
I have found what looks to be NOS of the exact same tank currently in the amp however, which looks like this:-
http://i1085.photobucket.com/albums/j437/stefbillington/Misc/ebay_zps2127fd13.jpg
These are available on eBay UK for £30.40 delivered (http://www.ebay.co.uk/itm/360818603092?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT), so a little bit more but perhaps worth it for an identical like for like replacement, or will the black on do the job too? I'd prefer to buy from Watford Valves.
Finally, the tank in the Laney has the red & black leads for connection to the amp soldered to the input and output already. Will a new one come pre-wired, or will I have to remove and attach the leads from the goosed tank?
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein
The fault was eventually diagnosed as the tank itself, and a new one has today arrived from Watford Valves.
Final question please @ICBM - does the quality of the RCA lead I use to connect the new tank matter too much, or will a standard 1m cable for a couple of quid be fine? The cable attached to the defective tank is soldered onto the terminal ends and so doesn't have phono jacks that can be connected to the new tank.
Easier for me just to source a new one, so does the quality of the lead matter? Cheers.
"Take these three items, some WD-40, a vise grip, and a roll of duct tape. Any man worth his salt can fix almost any problem with this stuff alone." - Walt Kowalski
"Only two things are infinite - the universe, and human stupidity. And I'm not sure about the universe." - Albert Einstein