KT77 in Diezel amps ?

[steve_k]

Yeah, I am currently very happy with the tone of my VH4 channel 3 and 4 with the SED Winged C 34's in it. Got some Ruby's to try out, but I can't be arsed now with pulling the amp from the road case and changing tubes. Think I will stick with the 34's instead of ordering 77's. With the Uber running alongside the VH4, I can let it sizzle and bring up the bottom end and leave the articulation to the VH4.

Ah shit, who am I kidding? Where's my screwdriver and multi-meter?




Steve

 

[King Crimson]

If I was to get the JJ KT77s for my VH4 what would I be looking at getting on my multimeter? 65mA? Peter seems to say there that 25mA each tube is good for distortion, would this then be 50mA?

Biasing still does confuse me, I know how to do it I just need to know the values to dial in

boulty, let me offer some assistance here.

One must ponder with great patience the following statement:

In the Herbert and Einstein You are measuring a pair.

Please start with 60 mA (pair)

Now we all know that Peter is packed with massive amounts of information that we all need regarding the proper care and maintenance of our beloved Diezel creations. However, English (with all due respect) is not Peter’s primary language. Hence, some interpretation may be in order to correctly optimize, elucidate and carry forth the all mighty torch of reasoning and predicate to which we all aspire to. With this in mind, when Peter refers to the two guitar amps that have been stated above as the bias being "measuring a pair" one might interpret this suggestion in one of several ways.

Now we all are striving to achieve that elusive holy grail of guitar amplifier tone in Heaven, but how to interpret the God of tone with one fell swoop of enlightenment can become an arduous task to commandeer.

Therefore to have "measuring a pair" while in the process of a bias, one would ask: is it sweet tone, or is it engaging tone, or is it winning tone, or is it charming tone, or is it appealing tone that we are after here.

On the flip side, being that the language factor may come into play while interpreting "measuring a pair" or is it "measuring a pear?" In which case one would ask, is it a pomaceous tone, or is it a fruity tone, or is it a genuine macintosh tone, or is it a subtle bitter tone that we are after here.

Either way, your ears' mileage may vary…

 

[Capulin Overdrive]

...and also the Tung-sol EL-34B

CO - what amp did you install the TS-EL34B into and at what bias setting? I tried them in my Herbert and (although very nice) I didn't find them enough of the a change that I was looking to hear away from the R-EL34BSTR.

i've tried them in 2 deferent modded Marshalls, they're good in the Golub modded and didn't like them in the Cameron modded.


also they sound good in Splawn Quickrods, and think Scott is now shipping amps with them.


i biased them at 70%, guess that's somwhere around 450-460 plate and around 39ma?


the reason i mentioned them, is that i'm pretty sure i read some technical data somewhere saying they will handle high voltages, but could be full crap just as easily?

 

[King Crimson]

i've tried them in 2 deferent modded Marshalls, they're good in the Golub modded and didn't like them in the Cameron modded.

also they sound good in Splawn Quickrods, and think Scott is now shipping amps with them.

i biased them at 70%, guess that's somwhere around 450-460 plate and around 39ma?

the reason i mentioned them, is that i'm pretty sure i read some technical data somewhere saying they will handle high voltages, but could be full crap just as easily?

Humm, interesting. I personally do not have any experiences with the Golub mod and the Cameron mod amps, but I’ve heard and read very good things about them.

I was a die-hard TS-12AX7 advocate for quite some time while still utilizing the originally stocked R-EL34BSTRs that Peter had installed in my Herbert at the time. I’m going on 6 years now with my Herbert (and I have never entertained otherwise since my introduction to Herbert) , and I love it more each time I play it while I always find something new to explore and enjoy with it.

However, being into the TS-12AX7s I naturally gave the TS-EL34Bs a shot but I found them (in my case) to be somewhat lack-luster to a very small degree in Herbert. I eventually went back to the original Chinese 12AX7A which I like very much for its nice bell-like tone, availability and aggressive punch in the mid-range while still keeping Herbert's three massive preamp sections nice and expressive.

Every since Peter mentioned that he liked JJ not to long ago, I gravitated towards JJ and I am now a convert. I hope it lasts, because my tube collection is in the hundreds now and growing…

 

[Duolos]

You are just learning about the JC 120?????? A must have amp for all.....IMO of course.

And regarding the tubes, I hear ya. The treble and presence knobs turn both ways if you need to adjust them...

I couldn't resist that one

I've had three of them over the years smarty pants. But I never had one given to me, and I never used one to accompany another amp in a stereo rig, K?

Also, this is a mint early '80s model when Roland gave a cat's meow about good tone.

Your tactfulness is impeccable!

Don't go tube happy and bias adjustment happy in the JC 120 ok...

 

[BigR]

In the Herbert and Einstein You are measuring a pair.

Please start with 60 mA (pair)

Peter,
I just replaced all 6 Ruby's in my Herbert w/JJ E34L's, and have a bias question for you, or anyone. At 180watts, I almost never have a chance to overdrive the power section, at least not without knocking a couple walls out of my house, and probably my neighbors house as well. My question is, should I be able to notice much difference by increasing the bias, considering that the power tubes are well below saturation? I can tell a difference, even at low volume, between the JJ's and the Ruby's, and am willing to sacrifice a little tube longevity for a warmer more organic sound, if a higher bias will get me there. I guess the best way to figure it out is trial and error, but if at lower volumes (not talking bedroom level, but probably in the 3/10 range on the total volume) a hotter bias wouldn't really be noticable, I'd save myself the trouble. I've been playing tube amps for about 2 years, and still have a LOT to learn about them to make my experimenting more worthwile. And THANK YOU for the external bias test and adjustment points on the Herbert. I'm still trying to learn how to even check the bias on my Ecstasy with just a multimeter.
Another question. Does anyone know of a good resource (book) for learning not only how tube amps work, but how to work on them? The ones I've seen so far only skim over the basics, and I'd like to learn to do most of the work on my amps myself, especially not knowing of a good tech in my area (I'm sure there are, I just don't know of them).
Sorry about the newbie questions, but this forum has been invaluable for me in learning how to get the most out of my gear.

 

[guitarobert]

My question is, should I be able to notice much difference by increasing the bias, considering that the power tubes are well below saturation? I can tell a difference, even at low volume, between the JJ's and the Ruby's, and am willing to sacrifice a little tube longevity for a warmer more organic sound, if a higher bias will get me there.

I'm not Peter but I can tell you that you will notice a difference in tone even at very low volumes by setting the bias higher. Higher will give you a warmer sound.

 

[Duolos]

I park my stuff at 65mA and it works for me. Going too high is going to cause you issues so don't do it. Peter designed a proper amp from the get go, trust in it and play away.

 

[BigR]

I'm not Peter but I can tell you that you will notice a difference in tone even at very low volumes by setting the bias higher. Higher will give you a warmer sound.

I park my stuff at 65mA and it works for me. Going too high is going to cause you issues so don't do it. Peter designed a proper amp from the get go, trust in it and play away.

Thanks. If I remember right, I set it at 68 or so when I retubed last week, so it sounds like I'm about where I need to be as far as balancing warmth vs. tube life or other issues.

 

[Peter Diezel]

BigR,

there are a lot of cool books. It only depends
where You want to start.

I don´t know if You are beginner or advanced
tech.

Please google a bit and You will find the right
lesson for You.

 

[BigR]

BigR,

there are a lot of cool books. It only depends
where You want to start.

I don´t know if You are beginner or advanced
tech.

Please google a bit and You will find the right
lesson for You.

Thanks Peter. I'm most certainly a beginner when it comes to amplifiers, and mainly want to learn for the sake of learning. My education/career background is in Mechanical Engineering/Physics, but its been quite a while since college, and electronics was NEVER my strong point (not even close) Off to Google I go

 

[nbarts]

I park my stuff at 65mA and it works for me. Going too high is going to cause you issues so don't do it. Peter designed a proper amp from the get go, trust in it and play away.

Would you care to shed a little more light?

I currently bias all my amps to 35ma (JJ E34Ls) & I REALLY REALLY like how they sound.

What issues may this cause?

 

[synchu]

Up for another praise.
Changed my Einy TAD EL34 for TAD supplied JJs KT77 (this must have been the easiest tubes change/bias in my life - changed/biased/up and running for 15-20 minutes) this weekend. Great move I am getting even more "chugga-chugga" now, which as you know makes the average metalhead (i.e. me) immensely happier Cleans do sound better now, as well.
However, EL34s are great choice as well. Have a bit more harmonic content (high-mids heavy, if you like this way of putting it), if you ask me.

 

[Sabotage]

Hi,

Has anyone tried Sino China Shuguang KT-77's in Einstein or other Diezels? Four of these cost around 60€. Some of the TAD EL34's are re-labeled Shuguang tubes.

 

[Duolos]

I park my stuff at 65mA and it works for me. Going too high is going to cause you issues so don't do it. Peter designed a proper amp from the get go, trust in it and play away.

Would you care to shed a little more light?

I currently bias all my amps to 35ma (JJ E34Ls) & I REALLY REALLY like how they sound.

What issues may this cause?

The plate voltage of our amps and the ability for those tubes not to fail is risky IMO if you go any higher then 65mA. The tube quality is not what it used to be on those tubes and I have had just as good of tone and less issues at 65mA. This is my experience and you may have better luck then me with the EL-34 tubes.

 

[nbarts]

Duolos,

Yes, I have to go through a few sets of tubes before I find a set that can last for a while. Since I use my amps for recording 95% of the time I don't really care about tubes' longevity & reliability that much. If they fail I can always replace them.

What I'm really interested is if this can cause any damage to my amps?

 

[duesentrieb]

Diezels have fuses and at neuralgical (sp?) points diodes to protect your amp from damage thru tube failure. Don't worry. Go ahead

 

[duesentrieb]

Btw I've never heard of Shuguang KT77s yet. I've used JJ KT77s though. Good tubes, no doubt.

I have to check some SED 6550 too

 

[Sabotage]

Btw I've never heard of Shuguang KT77s yet. I've used JJ KT77s though. Good tubes, no doubt.

I have to check some SED 6550 too

I saw while ago shuguang sino china KT77's on Banzaieffects.com website (now listed unavailable).

 

[Sabotage]

Offtopic! Hey guys do you need "cheap" preamptubes?

http://users.belgacom.net/TubeFest/inde ... et=d5.html

Sell your amp and buy one NOS telefunken