Preamp tubes - Marshall JTM30

[APB_4]

Should I get some new preamp tubes for my JTM30 it's still got the stock Marshall in at the minute. The tone is way better than my first amp which was a cheap SS. I was just wondering whether it will sound even better with new preamp tubes. I've already upgraded the power amp tubes so that shouldn't hold back the tone.

 

[Simon_F]

Re: Preamp tubes - Marshall JTM30

It will sound different with different pre-amp tubes. Whether it's better or not depends on what tubes you get and what tone you're after. To give an example, I changed the pre-amp tubes in my 2553 Silver Jubilee from Sovteks to JJs, and they really warmed it up - gave it a warmer, less bright tone. Just what I was after!

Pre-amp tubes are relatively cheap (unless you go for NOS Mullards etc...), so you can probably afford to experiment a bit. You don't have to worry about matched pairs like you do in the power stage, so you can consider using different tubes in different positions, depending on the tone you're after. The JJs were good for me.

Both Hot Rox and Watford Valves usually have a good selection.

 

[APB_4]

Re: Preamp tubes - Marshall JTM30

Thanks Simon.
What is so special about NOS Mullards can nobody make them the same now?

 

[Simon_F]

Re: Preamp tubes - Marshall JTM30

What is so special about NOS Mullards can nobody make them the same now?

Apparently not. Unless it's just a case of "they're vintage so they must be better". I have a couple of old Mullard ECC83s (not NOS). They're fine, but I don't find them noticably 'better' than the new JJs. I'm no expert though!

 

[Luke Duke]

Re: Preamp tubes - Marshall JTM30

I have a couple of old Mullard ECC83s (not NOS). They're fine, but I don't find them noticably 'better' than the new JJs. I'm no expert though!

This is what I've ALWAYS wondered. I weant from Sovtek's to JJ's and it really warmed the amp up. With preamp tubes you can also customize your front end, for les gain you could go with ECC81's or 82's I could tell a huge difference in the 81 and 83 in the Phase Inverter slot.

I will say that older tubes have longer running lives.

Luke

 

[APB_4]

Re: Preamp tubes - Marshall JTM30

Hmm interesting.

 

[Quencho092]

Re: Preamp tubes - Marshall JTM30

back then, industrial hardware and military equipment relied on tubes so they had much tighter tolerances when it came to quality control and design.

Your run of the mill 12ax7 in the 50's needed to work in military radio systems in korea during the war.

Now a 12ax7 just needs to produce sound in some kid's JCM 2000 so he can play at a house party. Big difference in 'tube responsibility'. If the kid's tubes fail, he can't play anymore, but if a squad's radio fails, they're as good as dead. that's why NOS have longer running lives, better components, and as a result, better tone in lots of cases.

 

[APB_4]

Re: Preamp tubes - Marshall JTM30

Nice info Quencho cheers.
Does anybody have anything to say about the tone of NOS compared to new valves.
I got my power amp valves from Watford Valves and they seem to have all sorts of crazy testing equipment to make sure you don't get a dud valve are they still of possibly lower quality?

 

[APB_4]

Re: Preamp tubes - Marshall JTM30

Bump. Does anybody around here use NOS tubes? Do they have better tone?
Also what preamp tubes would you recommend to warm it up and add a bit more crunch. Will this add a noticeable amount of crunch to the boost channel as well cos that's what I want.

 

[APB_4]

Re: Preamp tubes - Marshall JTM30

Bump

 

[Luke Duke]

Re: Preamp tubes - Marshall JTM30

Bump. Does anybody around here use NOS tubes? Do they have better tone?
Also what preamp tubes would you recommend to warm it up and add a bit more crunch. Will this add a noticeable amount of crunch to the boost channel as well cos that's what I want.

If you want to warm an amp up JJ's are the way to go with new tubes. The ECC83S is a very smooth nice sounding tube. I can see how in some amps they would be too dark. You can get them with matched triodes (I think) for a bit more oomph. I deal with Bob from Euro Tubes.

Luke

 

[APB_4]

Re: Preamp tubes - Marshall JTM30

Thanks Luke.

 

[Luke Duke]

Re: Preamp tubes - Marshall JTM30

Thanks Luke.

Hey man, no problem! I'm just glad I could help you out.

Like I said I could see how some would find the JJ's too dark in some amps, but I haven't heard any sovteks I like, so maybe I'm biased.....no pun intended. :laugh2:

Take a look see: www.eurotubes.com or call Bob at 503-659-7401. He is VERY helpful and knows his amps and tubes. He also has his own NOS tubes to A/B with. There ARE some guys (Aleclee and Puckboy come to mind) on the forum who use a lot of NOS and they'll be along soon enough, if you haven't heard anything from them by monday, I'd bump the post.

Luke

 

[APB_4]

Re: Preamp tubes - Marshall JTM30

bump

 

[Asomodai]

Re: Preamp tubes - Marshall JTM30

Actually i know a fact that the US and the UK army are Buying back all the NOS Mullards they had previously sold, because Valves are not affected by an EMP field. Valve Radios might be making a comeback!

 

[APB_4]

Re: Preamp tubes - Marshall JTM30

Anybody Use Nos Mullards???

 

[Luke Duke]

Re: Preamp tubes - Marshall JTM30

Too rich for my blood!

Luke

 

[stevie_bees]

Re: Preamp tubes - Marshall JTM30

back then, industrial hardware and military equipment relied on tubes so they had much tighter tolerances when it came to quality control and design.

Your run of the mill 12ax7 in the 50's needed to work in military radio systems in korea during the war.

Now a 12ax7 just needs to produce sound in some kid's JCM 2000 so he can play at a house party. Big difference in 'tube responsibility'. If the kid's tubes fail, he can't play anymore, but if a squad's radio fails, they're as good as dead. that's why NOS have longer running lives, better components, and as a result, better tone in lots of cases.

Same with transformers, they don't seem to be as bullet proof as they used to. The military spec makes quite a difference