Running Your 410 At 50W....Glad You Did?

Studio66 · **Joined:** Tue Apr 15, 2008 6:56 am **Posts:** 16

Just wanting to get a sense of how many are running your 100 watters at 50 watts?
And are you happy with that choice?
Any descriptions of tone are always appreciated [smilie=icon_biggrin.gif]

Thanks!

Machine Pagan · **Posted:** Thu Apr 22, 2010 1:52 pm

I have been running 50w for two years and never looked back. I think my tone has improved due to it.

MP

1337storm · **Posted:** Fri Apr 23, 2010 4:29 am

Tried it for a couple of months and went back to 4 tubes.
To me the 100W JVM sounds better with all 4 tubes in it,
tighter, punchier, better attack and definition, the difference
increases with volume.
To me the 50W JVM sounds better than the 100W with two
tubes pulled, i'm out on thin ice here, but somewhere there
seemes to be a mismatch (OT?) when running a 100W at 50W...
I think you will get alot of different answers to this question
and none of them will give you YOUR answer...
But since it's a very simple operation just go ahead and try it
out, only you can tell if you like it.

Andy · **Posted:** Fri Apr 23, 2010 8:43 am

I've run mine at 50w for ages now, mainly to get power amp distortion at lower volumes, if an outdoor
gig came up I'd probably pop in the other tubes too. It's cool to have the choice ...
... though a 50w switch would be cool [smilie=gt-happyup.gif]

joka07 · **Joined:** Wed Jul 14, 2010 2:42 pm **Posts:** 10

Andy wrote:

I've run mine at 50w for ages now, mainly to get power amp distortion at lower volumes, if an outdoor
gig came up I'd probably pop in the other tubes too. It's cool to have the choice ...
... though a 50w switch would be cool [smilie=gt-happyup.gif]

Maybee a stupid question:
BEFORE pulling two power amp tubes, do you rebias to 30-35mV so that you do not overload the poweramp tubes when they are only two (50w)?

Australian · **Posted:** Wed Jul 28, 2010 2:35 pm

joka07 wrote:

Andy wrote:

I've run mine at 50w for ages now, mainly to get power amp distortion at lower volumes, if an outdoor
gig came up I'd probably pop in the other tubes too. It's cool to have the choice ...
... though a 50w switch would be cool [smilie=gt-happyup.gif]

Maybee a stupid question:
BEFORE pulling two power amp tubes, do you rebias to 30-35mV so that you do not overload the poweramp tubes when they are only two (50w)?

Pull two tubes then you rebias.

joka07 · **Joined:** Wed Jul 14, 2010 2:42 pm **Posts:** 10

Australian wrote:

joka07 wrote:

Andy wrote:

I've run mine at 50w for ages now, mainly to get power amp distortion at lower volumes, if an outdoor
gig came up I'd probably pop in the other tubes too. It's cool to have the choice ...
... though a 50w switch would be cool [smilie=gt-happyup.gif]

Maybee a stupid question:
BEFORE pulling two power amp tubes, do you rebias to 30-35mV so that you do not overload the poweramp tubes when they are only two (50w)?

Pull two tubes then you rebias.

yes, I would (will) rebias after they are pulled, but it is best practice to also do it before so the amp is "scaled down", or adjusted, for 50W so you don't pull two tubes and switch on the amp in order to rebias and the amp is set for 60-70mV... My question is if this initial powering up of the amp , biased for 100W, is harmful.

Australian · **Posted:** Thu Jul 29, 2010 3:38 am

No you dont have to do that. Just Bias when two of the tubes are out.

satch4u3 · **Posted:** Thu Jul 29, 2010 8:08 am

I am running in 50W as well. It does change the headroom and the saturation of the preamp a little. Technically it only changes volume by 3db. A rebias would be recommended.

joka07 · **Joined:** Wed Jul 14, 2010 2:42 pm **Posts:** 10

satch4u3 wrote:

I am running in 50W as well. It does change the headroom and the saturation of the preamp a little. Technically it only changes volume by 3db. A rebias would be recommended.

would you say the only "benefit" is 3 db lower volume and the negatives are less headroom and less saturation?! Is it worth the effort, really?

satch4u3 · **Posted:** Thu Jul 29, 2010 12:40 pm

Quote:

would you say the only "benefit" is 3 db lower volume and the negatives are less headroom and less saturation?! Is it worth the effort, really?

With two tubes pulled it is actually a little eaiser to get a tad more saturation out of the preamp = less headroom. The reason why I did it to begin with was so that I don't have to drive my volumes up to loud to get that power tube distortion when I gig. To me that is a positive. To my audiences ears, it is a positive also. icon_smile

With this configuration I am now dialing in my preamp volumes at around 3:30 o'clock, and adjusting over all volume with my masters at around 9 o'clock, depending on the venue. I really like my sound this way.

Pulling the tubes won't completly change the overall sound and feel of the amp. But it definetly does a little. For me it was defiently worth it.

joka07 · **Joined:** Wed Jul 14, 2010 2:42 pm **Posts:** 10

satch4u3 wrote:

Quote:

would you say the only "benefit" is 3 db lower volume and the negatives are less headroom and less saturation?! Is it worth the effort, really?

With two tubes pulled it is actually a little eaiser to get a tad more saturation out of the preamp = less headroom. The reason why I did it to begin with was so that I don't have to drive my volumes up to loud to get that power tube distortion when I gig. To me that is a positive. To my audiences ears, it is a positive also. icon_smile

With this configuration I am now dialing in my preamp volumes at around 3:30 o'clock, and adjusting over all volume with my masters at around 9 o'clock, depending on the venue. I really like my sound this way.

Pulling the tubes won't completly change the overall sound and feel of the amp. But it definetly does a little. For me it was defiently worth it.

thanks for the info. I will be pulling tubes tonight.

One question: does this alter the ohm setting in any way? i run 16 ohm and would like to keep it that way after pulling two tubes because of my THD Hotplate (the 16 ohm version).

satch4u3 · **Posted:** Thu Jul 29, 2010 2:55 pm

Quote:

thanks for the info. I will be pulling tubes tonight.

One question: does this alter the ohm setting in any way? i run 16 ohm and would like to keep it that way after pulling two tubes because of my THD Hotplate (the 16 ohm version).

The way I am doing it is I have a 212 8 Ohm Mesa cab plugged into the 4 Ohm input on my head. The idea is half the ohmage.

Let us know what you think once your back up and running.

Australian · **Posted:** Thu Jul 29, 2010 10:56 pm

joka07 wrote:

satch4u3 wrote:

Quote:

would you say the only "benefit" is 3 db lower volume and the negatives are less headroom and less saturation?! Is it worth the effort, really?

With two tubes pulled it is actually a little eaiser to get a tad more saturation out of the preamp = less headroom. The reason why I did it to begin with was so that I don't have to drive my volumes up to loud to get that power tube distortion when I gig. To me that is a positive. To my audiences ears, it is a positive also. icon_smile

With this configuration I am now dialing in my preamp volumes at around 3:30 o'clock, and adjusting over all volume with my masters at around 9 o'clock, depending on the venue. I really like my sound this way.

Pulling the tubes won't completly change the overall sound and feel of the amp. But it definetly does a little. For me it was defiently worth it.

thanks for the info. I will be pulling tubes tonight.

One question: does this alter the ohm setting in any way? i run 16 ohm and would like to keep it that way after pulling two tubes because of my THD Hotplate (the 16 ohm version).

Heres a great thred that will give you the full answer. Andy gives a detailed explanation about it.
viewtopic.php?f=7&t=65&p=10067&hilit=2+tubes+pulled+ohms#p10067

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Running Your 410 At 50W....Glad You Did?

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