unclemack Posted January 28, 2017 Share Posted January 28, 2017 A mate of mine just had all his earthly goods shipped back from the UK and we found that one of his tubes had broken at the base. The amp is an Audio Innovation Series 800. I couldn't identify the tube but have taken a couple of pics. Can anyone help with finding a replacement for this? Cheers. M Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
rocky500 Posted January 28, 2017 Share Posted January 28, 2017 That close in photo shows OTK77 Maybe these? http://www.ebay.ie/itm/-/192020669143? Link to comment Share on other sites More sharing options...
Guest Terence Hill Posted January 28, 2017 Share Posted January 28, 2017 (edited) Russian 5U4G? On closer inspection, looks more like a twin triode. Edited January 28, 2017 by TEZZA Added info. Link to comment Share on other sites More sharing options...
rocky500 Posted January 28, 2017 Share Posted January 28, 2017 (edited) You could pull the stickers off the base and see if there is some writing underneath. these? http://www.tubes-store.com/product_info.php?products_id=152 http://rutubes.com/product/5c3s-5u3c-5u4g-tube/ http://www.ebay.com/itm/5U4G-5U3C-5C3S-SVETLANA-Tubes-1974-years-Lot-of-2pcs-RARE-/332094925767? Edited January 28, 2017 by rocky500 Link to comment Share on other sites More sharing options...
loki65 Posted January 28, 2017 Share Posted January 28, 2017 This any help?? http://www.borderpatrol.net/aiind.htm Link to comment Share on other sites More sharing options...
unclemack Posted January 28, 2017 Author Share Posted January 28, 2017 Thanks everyone. Will check out the links. Cheers M Link to comment Share on other sites More sharing options...
F18 Posted January 28, 2017 Share Posted January 28, 2017 The OTK 77 code means it was manufactured around that time in the plant (1977) but inspected and approved for mill-spec use, hence the OTK designation code. Your amplifier appears to have been modified based off the picture. All Series 800 amplifiers use 4 x EL34's for output and ECC82 for input/preamp. Use this as a guide: http://www.borderpatrol.net/aiind.htm 2 Link to comment Share on other sites More sharing options...
rocky500 Posted January 28, 2017 Share Posted January 28, 2017 25 minutes ago, willio747 said: The OTK 77 code means it was manufactured around that time in the plant (1977) but inspected and approved for mill-spec use, hence the OTK designation code. Your amplifier appears to have been modified based off the picture. All Series 800 amplifiers use 4 x EL34's for output and ECC82 for input/preamp. Use this as a guide: http://www.borderpatrol.net/aiind.htm Yes I picked the wrong markings. The code 5U3C is the one I should have mentioned. 1 Link to comment Share on other sites More sharing options...
Guest Terence Hill Posted January 28, 2017 Share Posted January 28, 2017 How about: Winged "C" (SED) 6C4C (6B4G) Link to comment Share on other sites More sharing options...
unclemack Posted January 31, 2017 Author Share Posted January 31, 2017 (edited) So, the bloke that sold the amps to my mate told him that the tubes are 6B4G. I've found some on Ebay but can these be bought locally? If not, does anyone have a reliable seller that they deal with? Sovtek 6B4G. Cheers M Edited January 31, 2017 by unclemack Link to comment Share on other sites More sharing options...
colclarke Posted January 31, 2017 Share Posted January 31, 2017 I recently picked up some kt150's and 6sl7 from Watford valves out of the Uk. service and pricing was pretty decent...I still try and source here first but I'd go back there if I lucked out here 1 Link to comment Share on other sites More sharing options...
unclemack Posted January 31, 2017 Author Share Posted January 31, 2017 40 minutes ago, colclarke said: I recently picked up some kt150's and 6sl7 from Watford valves out of the Uk. service and pricing was pretty decent...I still try and source here first but I'd go back there if I lucked out here Thanks mate but they don't seem to have the 6B4G... Cheers M Link to comment Share on other sites More sharing options...
RoHo Posted January 31, 2017 Share Posted January 31, 2017 A quick web search shows Parts Connexion in Canada have the Sovteks at USD145 a pair. I've bought from them multiple times with no problems. The Tube Store, also Canadian, have the Russian 6C4C version at USD35 each along with some NOS, you would need to email them for details. In Australia Evatco list various NOS types but no prices. Link to comment Share on other sites More sharing options...
Guest Clarence Posted January 31, 2017 Share Posted January 31, 2017 (edited) On 31/01/2017 at 6:26 PM, unclemack said: So, the bloke that sold the amps to my mate told him that the tubes are 6B4G. I've found some on Ebay but can these be bought locally? If not, does anyone have a reliable seller that they deal with? Sovtek 6B4G. Cheers M Brendan Biever at tubeworld.com in the U.S. is My Man. Curt, essential communications only, but accurate and all tubes individually tested, measured and photographed (WYSIWYG) for their entry to the website and those measurements penned to each tube's box for your own record. He does matched pairs, singles, quads and generally has no new stock but specialises in NOS and is very expert and very professional about his testing, measurements and equipment. He packages well and dispatches almost immediately and the service to Oz is fast. He generally has very unique tubes available where others have greatly reduced stocks, types and models in comparison. You will find also extremely rare and unique tubes here too harking back to far earlier ages for the more vintage machines and DIYers on a vintage binge. He has several 6B4G's listed currently including RCA and GE. Type 6b4g in the initial "Find a Tube" search string prompt and visit the list/s provided till you find in stock entries. 35 - 120 bucks in his range at the mo'. I have dealt with no one better than Brendan. Not to say any others I have dealt with have not been great too, but I always go to Brendan first if I'm looking for something and, other than NOS 300B's for the past few years and NOS 417A's the last couple, a great collection of stock is always available. HIGHLY RECOMMENDED. Edited February 2, 2017 by Clarence small change, unique, photos too Link to comment Share on other sites More sharing options...
VanArn Posted January 31, 2017 Share Posted January 31, 2017 It is possible to refit the glass envelope of the 6B4G to the octal base with a high temperature adhesive. This does presume that the electrode wires, all four of them, are intact or accessible for resoldering to the pins if this is needed. Otherwise rather than chasing up rare valves of the S/H or NOS variety , it may pay to convert the O/P stage to use valves such as the KT88 in triode mode with suitable modifications. 1 Link to comment Share on other sites More sharing options...
Mr Smith Posted February 1, 2017 Share Posted February 1, 2017 Try these guys, they have expanded their stock dramatically over the past few years and are Aussie. http://www.evatco.com.au/ Link to comment Share on other sites More sharing options...
Gremrock Posted February 3, 2017 Share Posted February 3, 2017 On 2/1/2017 at 9:43 PM, Mr Smith said: Try these guys, they have expanded their stock dramatically over the past few years and are Aussie. http://www.evatco.com.au/ I was going to recommend them too but I see i've been beaten to it, a friend tells me they are very good and have sourced everything he's needed. Link to comment Share on other sites More sharing options...
skies2clear Posted February 3, 2017 Share Posted February 3, 2017 On 28 January 2017 at 7:09 PM, willio747 said: The OTK 77 code means it was manufactured around that time in the plant (1977) but inspected and approved for mill-spec use, hence the OTK designation code. Your amplifier appears to have been modified based off the picture. All Series 800 amplifiers use 4 x EL34's for output and ECC82 for input/preamp. Use this as a guide: http://www.borderpatrol.net/aiind.htm Spot on. I've repaired many Series 800s and never seen this exact model. Must be an early variant and likely very few made it here to Aust. And it looks to have been modified. Not much help to the OP though. 1 Link to comment Share on other sites More sharing options...
Micoz Posted February 3, 2017 Share Posted February 3, 2017 Thanks @Mr Smith I followed up with Evatco about a rare 6H30 Octal that I have been chasing and they were great. Tremendous friendly service. Highly recommend them. 1 Link to comment Share on other sites More sharing options...
King Julien Posted February 4, 2017 Share Posted February 4, 2017 jacmusic.com has a great sales list updated regularly. Jac is really nice to deal with, and being the partner in Emission Labs, you can trust that he's selling authentic NOS I've checked his list and there's matched pair of Svetlana 6C4C for just under $120. Add shipping, I suggest express shipping Link to comment Share on other sites More sharing options...
F18 Posted February 4, 2017 Share Posted February 4, 2017 You could try ebay for Russian or European NOS. Prices could most likely be cheaper than the suppliers mentioned so far. Cheers, Link to comment Share on other sites More sharing options...
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