Hi Everyone,
I have an AMI R2777B Basic Amp plus the R2728A power amp.
Screened on top of the chassis is 6973 for the output tubes. However, they are not 6973 tube sockets.
They are a larger 8 pin socket which looks to be factory installed.
Did these amps ever come out with say 6L6 tubes? The wiring on the sockets suggest it may be these as pin 1 and 6 are not connected, but I couldn't find any info to support this.
Thanks
Iain Pintech Ltd Unit 9, 37 Washbournes Road Wigram Christchurch Ph 0273333716
On 3/17/23 15:26, Iain Jamieson via Jukebox-list wrote:
Hi Everyone,
I have an AMI R2777B Basic Amp plus the R2728A power amp.
Screened on top of the chassis is 6973 for the output tubes. However, they are not 6973 tube sockets.
They are a larger 8 pin socket which looks to be factory installed.
Take pictures of the top and bottom and post to imgur.com. Send a link to the list. It's possible they're configured for octal tubes from the factory or it was converted if 6973s were unavailable. Could be 6L6, more likely 6V6 or 7591. Heater current for 6L6 is double that of 6973 and could overload the transformer.
Did these amps ever come out with say 6L6 tubes? The wiring on the sockets suggest it may be these as pin 1 and 6 are not connected, but I couldn't find any info to support this.
On the original 6L6 (and most octal metal can tubes), pin 1 is connected to the metal case and used as a shield. This was typically tied to chassis ground. Glass 6L6 tubes have pin 1 unconnected and it is often used as a tie point.
I noticed that you're in NZ. AMI jukes or parts for them outside of the US were often partially sourced locally, sometimes under the BAL-AMI label. In that case it's possible that your amplifier is substantially different from the USA version.
Hi Iain,
What does the serial plate on the back door say? Does it also specify the voltage?
I suspect you have a variant of the American amplifier built in your country.
I live in England and have seen imported Amis from Italy made by microtecnica, nova from Germany, Eden, International. This was common practice around the age of your machine due to import restrictions etc. We in the UK had bal Ami. There are all manner of genuine variations on that amp I've seen, with different tubes in
I reckon maybe the local factory probably screen printed 6973 on by genuine error because they were copying the American one. Obviously the size of the valve base hole in the metal is bigger with yours, so it could not have been an enthusiast hacking around as the 6973 print would have disappeared when they enlarged the hole for the valve base. I've seen Rowe Ami JAL jukeboxes with continental mechanisms. And continentals with Ami I amplifiers. All legitimate.
I think, ignore the print. You're in a better position with yours as the 6973 can be a bit of a fussy tube and there are lots of badly made repros of it about.
Nigel, uk
On 17 Mar 2023 at 23:42, Iain Jamieson via Jukebox-list jukebox-list@lists.netlojix.com wrote:
Hi Everyone,
I have an AMI R2777B Basic Amp plus the R2728A power amp.
Screened on top of the chassis is 6973 for the output tubes. However, they are not 6973 tube sockets.
They are a larger 8 pin socket which looks to be factory installed.
Did these amps ever come out with say 6L6 tubes? The wiring on the sockets suggest it may be these as pin 1 and 6 are not connected, but I couldn't find any info to support this.
Thanks
Iain Pintech Ltd Unit 9, 37 Washbournes Road Wigram Christchurch Ph 0273333716 _______________________________________________ Jukebox-list mailing list -- jukebox-list@lists.netlojix.com To unsubscribe send an email to jukebox-list-leave@lists.netlojix.com %(web_page_url)slistinfo%(cgiext)s/%(_internal_name)s Searchable Archives: http://jukebox.markmail.org/
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