MK 11 help needed from a noobie in UK

[AndyK]

Hi guys,

I am an Essex guy ( Southeast UK) who believes he has owned a MK11B since the mid eighties. It has been a case of I found the sound and just plugged in and played, never look closely around the back or did any research.

Aftergoing through the 'Rack' period in my life, I have now started to home record, and the Boogie has come out of a 10 year retirement (but has been looked after.

Deciding to re tube her, I looked more closely and now I now question her
age. The serial no is 4760. The speaker is an Altec 417. I am also puzzled with the switch ' switch to right for TR1009 Fetron '. This has never been touched and is switched to the right. What difference would be if it was on left 12ax7 mode. Also there appears to be only 4 x 12ax7. Going from right to left looking at the very back, there are three 12ax7, far left there is a blank hole where it looks like there should be something but no fittings available

If any of you guys could shed some light on this I would be very appreciative. I am in the process of getting tubes from Dougs but would like to know exactly what I have.

Many Thanks

Andy King

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[Boogiebabies]

Sounds like a IIA with no reverb. If you switched to the 12AX7 from the TRI009, it would be an massive improvement in tone.

 

[AndyK]

Thanks for the reply Boogiebabies.

As you can see from the attached photos re links below, I did nt realise there was a date written there ( 02/12/80 )

I am now going to try with the switch and see what I get.

Many Thanks

 

[Boogiebabies]

Flip it back and forth a few times before you fire it up to get any dust or grime off the contacts.

 

[jvk]

Hi Andy, welcome to Boogieboards. Jonny here from Reading, UK

Nice amp. Are you using that patch lead as a speaker cable? Shielded wire can't handle speaker output levels and tone will be lost.

 

[AndyK]

Hi Jonny,

Thanks for the reply and your welcome.

Yes I am. Thanks for the heads up, I will switch to a speaker cable. I am going into an attenuator, which I know causes a great deal of debate as regards tone as well.
I believe that the amp deserves a full suite of new valves after all these years, just working out what to get.

Thanks

 

[ramalam]

Just because the tubes are old doesn't mean they aren't good. They could be extra good as a matter of fact. They used some very sought after tubes back then.