Adjustable-Bias-Kit in Stiletto GREAT SOUND!

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Charles Reeder
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by Charles Reeder » Tue Aug 03, 2010 1:22 pm

Hey 'Riff Blister':
It'll be the 'best year you ever lost' when you get that bias-kit installed and set properly.
I've experimented a bit and I keep coming back to a setting between 36-39mv. (currently at 39mv). That seems to come closest to the sound (and feel) I got from my old classic 'Marshalls'. That is at the pount where the painful harshness of a cold-biased Stiletto starts to fade and the rich bloom of harminic distortion in the midrange and highs starts to set in..Not too hot-not too cold goldilocks.
Regards: Charles

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Riff Blister
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by Riff Blister » Tue Aug 03, 2010 3:35 pm

Very good news Charles. I'm anxious to hear the difference for myself. I'm 53 and grew up with those great Marshall tones as well as the classic Fenders tones. If I can get close to that classic Marshall like tone I'd be over the top happy. I must say in all honesty that after some tube and speaker changes I've been quite happy with my Stiletto as of late. When news of the adj. bias mod came along I figured why stop now. :)

Mark
Stiletto Deuce II, with bias mod - 2x12 Recto Cabt. Scumback M75s inside
Bogner Shiva EL34 80 watt
Budda Superdrive II 45
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TTSTWO
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by TTSTWO » Wed Aug 04, 2010 11:40 pm

I'd be interested to know if anyone has done this mod to a Stage 1 Stiletto AND how do they like it.

(Side note) I just added up the prices for all the tubes (Mesa branded) for my Trident....6 EL34, 5 12AX7 and 3 5U4GB's with tax will run around 310 bones.....OUCH! :mrgreen: The reason I mention this is because running hotter = shorter tube life, not a big deal if it improves your tone to your taste.
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-Mesa 4 X 12 Recto Slant Cab V-30's

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Riff Blister
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by Riff Blister » Thu Aug 05, 2010 9:45 am

TTSTWO wrote:I just added up the prices for all the tubes (Mesa branded) for my Trident....6 EL34, 5 12AX7 and 3 5U4GB's with tax will run around 310 bones.....OUCH! :mrgreen: The reason I mention this is because running hotter = shorter tube life, not a big deal if it improves your tone to your taste.
Yeah, I agree. Since we Stiletto guys pull in the big cash at our high paying gigs, money is really not an issue anyway. Right? :roll:.
Actually, I have not played out since last September. That pesky prostate cancer thing I had to deal with put my band on hold.

Back on topic though.....
I just put in a new quad on EL34s a couple of weeks ago. I'm wondering now (limited knowledge in this area) if they will have to be replaced after my amp is re-biased in the 36-39mv areas that Charles has been working with?
Stiletto Deuce II, with bias mod - 2x12 Recto Cabt. Scumback M75s inside
Bogner Shiva EL34 80 watt
Budda Superdrive II 45
’79 Gibson Les Paul Custom Silverburst
’85 Gibson SG ’61 Reissue
Fender American Standard Stratocaster and Telecaster

Charles Reeder
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by Charles Reeder » Thu Aug 05, 2010 12:22 pm

The tubes will NOT need to be replaced...just have the bias adjusted. The advantage of having an adjustable bias circuit....(which is what this kit gives you)...is that you can adjust ANY set of tubes to the desired bias level.

More than likely the tubes you just put in are presently running somewhat cold. So, take a reading and adjust the tiny set screw on the bias kit accordingly; until you get within the bias range you were aiming for.

As for tube life...39mv is not terribly hot....36mv less so. But, you will lose some tube-life...but it is worth it tonewise. With adjustable bias; you are no longer a 'slave' to the necessity to buy Mesa branded color-coded tubes....so re-tubing expense goes down.

None of the Mesa tubes I tried would get my bias any higher than 28mv. Granted; I could have missed a color that would have gotten me there; but I doubt it. The 36-39mv range seems to be the critical area 'tonewise'. This is where the harshness and cold piercing treble starts to get under control; and upper harmonics start sweeping in. No contest for me. My Stage-1 Stiletto Deuce now sounds like it should (to me at least)

Charles
Last edited by Charles Reeder on Thu Aug 05, 2010 12:32 pm, edited 1 time in total.

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Riff Blister
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by Riff Blister » Thu Aug 05, 2010 12:32 pm

Perfect. Thanks Charles. Like I said this is new stuff for me so do I appreciate the input.
Stiletto Deuce II, with bias mod - 2x12 Recto Cabt. Scumback M75s inside
Bogner Shiva EL34 80 watt
Budda Superdrive II 45
’79 Gibson Les Paul Custom Silverburst
’85 Gibson SG ’61 Reissue
Fender American Standard Stratocaster and Telecaster

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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by TTSTWO » Thu Aug 05, 2010 5:17 pm

Thanks, Charles. That put's my mind at ease. I will be looking into this mod in the future.
Mesa Engineering
-Mesa Stiletto Trident Stage 1
-Mesa 4 X 12 Recto Slant Cab V-30's

Fender and Ibanez guitars

Gordybaby
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by Gordybaby » Fri Aug 06, 2010 12:20 am

Where do you buy tubes that will get you in the high 30's mv range. I have a bias kit on the way.

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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by siggy14 » Fri Aug 06, 2010 12:22 pm

Everyone should take note, if you are not interested in modding your amp, there are many dealers where you tell them your amp, and you want a hotter tube and they can match you with a tube that will run hotter in your amp so this eliminates the need to add a bias control.
Charles Reeder wrote:The tubes will NOT need to be replaced...just have the bias adjusted. The advantage of having an adjustable bias circuit....(which is what this kit gives you)...is that you can adjust ANY set of tubes to the desired bias level.

More than likely the tubes you just put in are presently running somewhat cold. So, take a reading and adjust the tiny set screw on the bias kit accordingly; until you get within the bias range you were aiming for.

As for tube life...39mv is not terribly hot....36mv less so. But, you will lose some tube-life...but it is worth it tonewise. With adjustable bias; you are no longer a 'slave' to the necessity to buy Mesa branded color-coded tubes....so re-tubing expense goes down.

None of the Mesa tubes I tried would get my bias any higher than 28mv. Granted; I could have missed a color that would have gotten me there; but I doubt it. The 36-39mv range seems to be the critical area 'tonewise'. This is where the harshness and cold piercing treble starts to get under control; and upper harmonics start sweeping in. No contest for me. My Stage-1 Stiletto Deuce now sounds like it should (to me at least)

Charles

Charles Reeder
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by Charles Reeder » Sat Aug 07, 2010 11:45 am

Gordybaby:
Once you install the bias-kit...ANY tubes you have on hand already...PLUS ANY you order...can be gotten into your target range by adjusting the bias. That's the great advantage of the bias kit....for about the cost of a pair of tubes...suddenly all EL34 tubes you own or order are usable.

Siggy14:
You are correct...some tube dealers offer tubes which will get you into a certain bias range. I'm not sure how reliable their claims are, though. I've communicated with several people who requested tubes within a certain range for several different Mesa amps. When they tested them with their bias probe and a digital multimeter they were not very close to the claimed bias.

The desire for the bias kit...is a desire to 'take-control' of the situation personally. and make use of the tubes I already owned which weren't in the warm or hot range. As stated before; for the cost of one-pair of tubes...the 5-useless pairs I had on hand became useful. Good economics if you ask me.

Assuming you can reliably get tubes that match the range you seek from a seller...that's certainly a viable option if you don't want to have to 'fiddle' with your amp. It's a matter of choice...and no solution is the wrong one.

Cheers: Charles

jetdriver
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by jetdriver » Sun Aug 08, 2010 11:34 am

Interesting stuff guys. I am already pretty pleased with the tone of my Deuce. Any of you guys wanna put up some videos, or audio clip comparisons that would be MUCH appreciated.
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Trev57
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by Trev57 » Fri Aug 13, 2010 2:05 am

I finally got my bias mod kit today ($13.45 Priority Mail from the USA - Mansfields please note). I should be able to find some time over the weekend to play with it. I am very interested to see what it does for the crappy Stiletto lead tone, but since I had my first band rehearsal last night with my new Mark V, I can't really imagine the Stiletto sudenly being able to do anything that would make me want to keep it. But I go into this little project open minded.

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inkwachemis
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by inkwachemis » Fri Aug 13, 2010 8:22 pm

Trev57 wrote:I finally got my bias mod kit today ($13.45 Priority Mail from the USA - Mansfields please note). I should be able to find some time over the weekend to play with it. I am very interested to see what it does for the crappy Stiletto lead tone, but since I had my first band rehearsal last night with my new Mark V, I can't really imagine the Stiletto sudenly being able to do anything that would make me want to keep it. But I go into this little project open minded.

defintely let us know what you think of it once you give it a go. I"m following this thread closely
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mansfieldguitars
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by mansfieldguitars » Sun Aug 15, 2010 4:45 pm

Due to the lack of tracking and past problems with priority mail international I only ship express international. It is more money but there are far less issues with lost shipments and mush better tracking. Please understand I cannot afford to eat the cost everytime the post office loses a package and they are great at that.

Thanks
John
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mansfieldguitars
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Re: Adjustable-Bias-Kit in Stiletto GREAT SOUND!

Post by mansfieldguitars » Sun Aug 15, 2010 4:45 pm

Due to the lack of tracking and past problems with priority mail international I only ship express international. It is more money but there are far less issues with lost shipments and mush better tracking. Please understand I cannot afford to eat the cost everytime the post office loses a package and they are great at that.

Thanks
John
Image

A full service guitar and amp repair shop

Mansfield Guitars
https://www.facebook.com/pages/Mansfiel ... 3783515762
jmansf3@comcast.net

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