Tube Behavior - ECC823 Thread:

So, based on a LOT of research - and gleaning tube knowledge from Bea and other distinguished TTR members herein - it looks like tonight's performance will feature the following tube assignment:

V1: JJ ECC823 - Gain Factor 100 / 20

V2: 7025-WA -

V3: JJ ECC83 MG

V4: JJ 5751 - Gain Factor 70

Unless I am missing something here, I feel like this will make the best use of the tubes I currently have on hand.

Arranged in this fashion, the gain factors are always descending. That made sense to me for some reason...
 
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Hello, Everybody, especially @Robert Herndon ,

I'm jumping into this thread cold, having read nothing above. However, I'll share with you what works with my DSL15c.
I have not looked at a DSL40c schematic, so I'm hoping that the gain structure is similar. In V1, the ECC823 will keep the
Green channel with normal gain, and the other half of the 823 will significantly reduce gain for the Red channel. No need to
get into technical details, since that is the end result. The Red channel will still have significant gain, but I can use it up to
9:00 without fizz. Because 5751 tubes function as direct replacements for 12ax7 (ESS83s), but with comparable gain reduction
to the 823's second side, I use a 5751 valve in V2, and a balanced 5751 for the PI in V4. V3, I keep as a regular 12ax7 (ECC83S).
All of these are JJ valves.

I do the same with my Orange OR15 and Dark Terror, with groovy results. I enjoy 70's-80's rock and LA metal, so I don't have a
need for intense, over-the-top gain. This combination delivers.
 
You won't need an expensive balanced tube in the PI. The circuity itself is not perfectly symmetric.

But in other words: if You want a gain reduction on both channels You'd probably need something like a ECC82, 12AY7 or 5751 also in stage 1.

And indeed: You can overdrive even the 2nd stage of a ECC83 with the 1st one, and it'll sound "ok".
 
Ok....a big improvement. I was able to run a lot more gain (higher knob settings) with clarity and punch - without any muddiness.

Here's tonight's settings:

IMG_20190117_40621.jpg

Previously, (with ECC-83-MG / 5751 / ECC-83-S / 7025-WA) I couldn't run the gain over 4 on 'Lead 2' and over 7 on Lead 1 without the tone becoming distorted, loose and muddy.

After the Goldmember Recommended Tube Swap, I could crank the gain to '10' on Lead 1 without it getting loose and muddy, although it really sounded better around 4-6 on the knob.

Got some very good tones tonight, even though it was a "off-night" for everyone and the drummer's shoulder was bothering him.

We called it early, but I have to say that I am impressed with this current tube arrangement:

V1 - JJ-ECC823

V2 - JJ-5751

V3 - JJ-ECC83MG

V4 - 7025WA

Just wondering if the ECC83-MG might be better in V2 and the 5751 in V3??? Seems to me the gain factor should always be descending from V1 to V4.

Thoughts???
 
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Robert Herndon said:
Ok....a big improvement. I was able to run a lot more gain (higher knob settings) with clarity and punch - without any muddiness.

Here's tonight's settings:

View attachment 21271

Previously, (with ECC-83-MG / 5751 / ECC-83-S / 7025-WA) I couldn't run the gain over 4 on 'Lead 2' and over 7 on Lead 1 without the tone becoming distorted, loose and muddy.

After the Goldmember Recommended Tube Swap, I could crank the gain to '10' on Lead 1 without it getting loose and muddy, although it really sounded better around 4-6 on the knob.

Got some very good tones tonight, even though it was a "off-night" for everyone and the drummer's shoulder was bothering him.

We called it early, but I have to say that I am impressed with this current tube arrangement:

V1 - JJ-ECC823

V2 - JJ-5751

V3 - JJ-ECC83MG

V4 - 7025WA

Just wondering if the ECC83-MG might be better in V2 and the 5751 in V3??? Seems to me the gain factor should always be descending from V1 to V4.

Thoughts???
Click to expand...
Now that you know what that configuration will produce for you, please try it again with a 12AX7/7025/ECC83 ( All the same ) in V2. Then report back to us... :fingersx:
 
You know, the footswitch only allows switching between clean and overdrive channels. Is it possible to be able to configure it to switch between Lead 1 and Lead 2????
 
I don't know to much on new production tubes A friend who I trust claims they don't draw as much current as the NOS.

On my builds the new production tubes fry quick on the PI but I'm running 300 VDC / 300 VDC on the PI Tube data for a 12AX7 250 VDC

I use Seimens 12AX7 1957/1962 for the PI 10,000 hour tube. I did score a box of 50 Raytheon 12AX7 black plates NOS $22.00 each

On my Marshall's I use Brimar 12AX7 1/2 price of the Mullard NOS.
 
Robert Herndon said:
You know, the footswitch only allows switching between clean and overdrive channels. Is it possible to be able to configure it to switch between Lead 1 and Lead 2????
Click to expand...

Sure 3 relays it is a complex modification power supply for the relays voltage regulator 3 relay boards switchcraft 7 pole connectors male and female and a triple foot switch and modified for led's 8 wire shielded cable. If there is room in the chassis. Big if.
 
67plexi said:
Sure 3 relays it is a complex modification power supply for the relays voltage regulator 3 relay boards switchcraft 7 pole connectors male and female and a triple foot switch and modified for led's 8 wire shielded cable. If there is room in the chassis. Big if.
Click to expand...
… THIS!

It can be done, but at what cost? Might as well get a Marshall JVM215C and call it a night! Don't look at the price!

Or... Use a "boosting pedal" to change up the Lead 1 channel.
 
67plexi said:
Sure 3 relays it is a complex modification power supply for the relays voltage regulator 3 relay boards switchcraft 7 pole connectors male and female and a triple foot switch and modified for led's 8 wire shielded cable. If there is room in the chassis. Big if.
Click to expand...

Wow!!!

I guess this one was modded with an external footswitch....?????

 
syscokid said:
… THIS!

It can be done, but at what cost? Might as well get a Marshall JVM215C and call it a night! Don't look at the price!

Or... Use a "boosting pedal" to change up the Lead 1 channel.
Click to expand...

It's not a big deal...Lead 2 isn't really useful for anything but solos....
 
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