Let's talk about the Ashdown Little Bastard

[Wasnex]

I’ve actually found the CTM -30 to be much cleaner than I thought it would be from reading this thread.

This could be due to the version. Both of my LB30s play about the same volume, but the Mk2 is cleaner and more mid scooped than the Mk1. If I turn up the tone controls beyond a certain point, the preamp in the Mk1 starts to drive. I can max out the tone controls of the Mk2 and the preamps stays clean.

Pretty sure the CTM 30 came in at least two versions.

 

[rickdog]

My lb2n is making squeaky/squealy sounds while playing. Anyone with experience know what that is? I have guesses but hoping to hear from those with experience. Thanks.

I've never experienced squeaky/squealy sounds with my CTM-30. But from my general tube experience, my first thought is a microphonic tube. Do you have the amp on top of the cab, or pretty close to it? Does it still happen if you move it away?

If I were having this problem, I'd open up the amp, power it up, turn it up, and tap gently on each preamp tube with my plastic chopstick. A little "tink" is okay, a big "clonk" is a bad sign.

 

[Mark Andrew]

This could be due to the version. Both of my LB30s play about the same volume, but the Mk2 is cleaner and more mid scooped than the Mk1. If I turn up the tone controls beyond a certain point, the preamp in the Mk1 starts to drive. I can max out the tone controls of the Mk2 and the preamps stays clean.

Pretty sure the CTM 30 came in at least two versions.

That would explain it thanks

 

[Joris 55]

I’ve actually found the CTM -30 to be much cleaner than I thought it would be from reading this thread. At the volume I will be using it for acoustic work it is completely clean. Haven’t opened it up more than half yet to see what volume the dirt begins …. No idea if I can use it for electric material also. But to be honest much more clean headroom than I thought!

Sure, but not clean like your average DI signal. Tons of headroom indeed, really nice sound.

*edit Different versions it would seem.

 

[Mark Andrew]

Searched the thread for DI and only got my own post as a hit . What are the experiences with the DI ? Curious on the opinions!

Photo was promised I believe apologies voor the lighting!

 

[BassBeginer64]

Since I been on roll lately on tube rolling some of my amp heads, is there a EL84 upgrade tube out there I been looking around they all seem to be 12-14 watts rated.

 

[Wasnex]

Since I been on roll lately on tube rolling some of my amp heads, is there a EL84 upgrade tube out there I been looking around they all seem to be 12-14 watts rated.

I researched various tubes several years ago. These are my notes for EL84


Tung Sol 7189, JJ, Shuguang/Valve Art/TAD, Sovtek EL84M, Preferred Series 7189 (The Tube Store). Tung Sol 7189 appears to be very highly rated for sound and durability. There are three different version of TADs M, CZ, and STR, they may not fit due to height and width differences. I suspect TAD M = Sovteks, CZ = JJ, and STR = Shuguang. Preferred Series 7189 is a heavy duty EL84 that is rated for higher plate voltage and dissipation. The Preferred Series 7189 is actually a Russian 6N14N-EB (6P14P-EV). There are other 6N14N variants with different suffixes. The EB/EV suffix has the longest (10,000hr) rating.

For TAD EL84-STR see post #4 The TAD EL84-STR is a rebranded version of......?? Good tube but may not be an ideal choice for an AC30.

I do not claim this info is correct or up-to-date

 

[JIO]

So this thread had me pull out my LB and implement it into my music room. I have so much stuff but only gig a P bass, Fender Rumble 500c, and my nano pedal board.

Here it is matched with a great cab; TecAmp M210!
View attachment 4394428 View attachment 4394429

I just learned that EICH (Germany) was originally called Tech and wonder if TecAmp was related. It 'looks' similar. Are TecAmps made in Germany?

This is a 1x15 w/horn EICH cab -

 

[Wasnex]

I just learned that EICH (Germany) was originally called Tech and wonder if TecAmp was related. It 'looks' similar. Are TecAmps made in Germany?

This is a 1x15 w/horn EICH cab -

View attachment 5240212

I don't know the story, but my perception is Eich came out of TecAmp. Maybe this will explain: TECAMP Closing | TalkBass.com

 

[FronTowardEnemy]

I just learned that EICH (Germany) was originally called Tech and wonder if TecAmp was related. It 'looks' similar. Are TecAmps made in Germany?

This is a 1x15 w/horn EICH cab -

View attachment 5240212

Yes TecAmp was made in Germany. The main guy, Eich, who started it left TecAmp and created Eich. Same cab specs with different branding.

 

[rickdog]

I researched various tubes several years ago. These are my notes for EL84


Tung Sol 7189, JJ, Shuguang/Valve Art/TAD, Sovtek EL84M, Preferred Series 7189 (The Tube Store). Tung Sol 7189 appears to be very highly rated for sound and durability. There are three different version of TADs M, CZ, and STR, they may not fit due to height and width differences. I suspect TAD M = Sovteks, CZ = JJ, and STR = Shuguang. Preferred Series 7189 is a heavy duty EL84 that is rated for higher plate voltage and dissipation. The Preferred Series 7189 is actually a Russian 6N14N-EB (6P14P-EV). There are other 6N14N variants with different suffixes. The EB/EV suffix has the longest (10,000hr) rating.

For TAD EL84-STR see post #4 The TAD EL84-STR is a rebranded version of......?? Good tube but may not be an ideal choice for an AC30.

I do not claim this info is correct or up-to-date

I really wish JJ would make a proper 7189A equivalent. The old GE 7189A datasheet I have shows maximum plate voltage 440V (JJ EL84 is 300V), and gives an example of a class AB push-pull amp making 24W with a pair.

I think I've seen a hint somewhere that the JJ EL84 can be run at higher plate voltage as long as the screen voltage is kept down... anyone know anything about this?

Oh, and the link to thegearpage.net was interesting, and not just for the technical content... let's just say it made me appreciate the diligent moderators here on TB

 

[BassBeginer64]

I think I have a quad set of (6P14P-EV), but the LB30 has a fixed bias

 

[JIO]

I don't know the story, but my perception is Eich came out of TecAmp. Maybe this will explain: TECAMP Closing | TalkBass.com

Yes TecAmp was made in Germany. The main guy, Eich, who started it left TecAmp and created Eich. Same cab specs with different branding.

Thanks for confirming that for me.

 

[Wasnex]

I think I have a quad set of (6P14P-EV), but the LB30 has a fixed bias

The LB30 is cathode biased--the tube bias themselves.

The bias develops across cathode resistor(s). The Mk1 LB30 has a two series cathode resistors for each tube. Total series resistance is 320 ohms for each tube.

Here are the readings for my Mk1 at 120V line

Plate = 329V
Cathode = 10.5V to 11.5V
Effective Plate = Average 318V
Total Cathode Resistance = 320 Ohms
Calculated Cathode Current range = 32.8-35.9mA
85% dissipation = 32.1mA
90% dissipation = 34mA
95% dissipation = 35.8mA

The hottest tube is running right at the limit (95%)

The amp idles at 0.92A, 120V

I haven't taken these readings on my Mk2, but the amp idles at 0.84mA, 120V, so it's probably running a bit cooler.

 

[BassBeginer64]

this with the (6P14P-EV) tubes, correct

 

[Wasnex]

this with the (6P14P-EV) tubes, correct

If they were sold as direct subs for EL84, they should be plug N play in the LB30. You can monitor the amp after installing the tubes to see if it gets unusually hot. Also observe for red plating tubes.

 

[BassBeginer64]

would this push the watts up to about 40 watts

 

[Wasnex]

would this push the watts up to about 40 watts

It might make more power, but I wouldn't expect a 33% increase. Also, it might make less power.

 

[JIO]

Chocolatey

 

[Nuage420]

Chocolatey

View attachment 5240951

I'll bet that sounds amazing!