MC275 Mk. VI with Raytheon 6414 tubes?

[Lockheed Mar]

The 12AT7 tubes on my MC275 Mk. VI are old and need to replace. Could I use these Raytheon 6414 tubes on 12AT7 spot.

Thank you.

 

[ron-c]

Not if you want the amp to operate correctly.

Ron-C

 

[Lockheed Mar]

Thank you very much, Ron. I should sell them and buy some 12AT7. Could you advise me some good NOS 12AT7, my power tubes are KT88-Z.

Thanks.

 

[4-2-7]

The 12AT7 tubes on my MC275 Mk. VI are old and need to replace.

They can't be that old if they are factory, the small signal tubes last a very very long time. It's the KT88's that get to the point of needing replacement a lot sooner. If you want to change tube for the sake of seeing if you get another sound quality that's one thing.

 

[mkane]

Something like this bought from Mcshane

 

[oregonalex]

I suggest NOS Mullard CV4024 / 12AT7. They can be had for not much more than new issues. Very pleasant sound and will last for a very long time. They do that sexy flash on startup, but the effect is largely lost in the mkVI due to the startup LEDs.

 

[mkane]

as shown in pic above

 

[jblnut]

Seconded on the CV4024's. I rolled those into my MC275 IV and loved the results.

jblnut

 

[Lockheed Mar]

Thank you, I would roll some Mullard CV4024 for my MC275.

 

[rudolfo]

How is the sound of these tube when it come to bass? and also the detail of mid's and hi's. I want to try it on my 300b amp.
How do I know if they are the original NOS?
Any takes?

 

[oregonalex]

How is the sound of these tube when it come to bass? and also the detail of mid's and hi's. I want to try it on my 300b amp.
How do I know if they are the original NOS?
Any takes?

As they are relatively inexpensive, your best bet is to buy a pair and listen for yourself. As you know, tube sound is circuit dependent. But they are good tubes, well balanced, with slightly more clarity and detail than the stock McIntosh/JJs. As for being genuine, buy them from a reputable dealer, such as tubedepot.com or upscaleaudio.com. If they look like the one in the picture above, you are all set. They are relatively inexpensive and plentiful and I don't think the fakers have so far bothered with this tube. There are other much more profitable tubes to fake...

 

[Chubba]

Even better is the Mullard M8162.It is an 12at7.Worth checking out.They are what I use as well as the CV4024.