Tube question : TAD RT372 vs RT272

[eh là bas ma]

Hello,

I need a new spare set of tubes for my Blues Junior 3 : 3x ECC82 and 2x EL84

The original tubes are getting fried one by one after 9 or 10 years of service. EL84 were GT Groove Tubes, the ECC82 are still fine so far, but i guess after 10 years they will also fry sometime soon.

Looking at thomann's products, i wonder if it's worth the extra 20 euros to buy the RT372 ?

They say it has a longer lifespan, is it significantly better than RT272 ?

I guess i don't mind paying a little more money, if it means several additionnal years of use.

TAD RT372 Tubes EL84M Pair

Paire de lampes La plus longue durée de vie sur le marché, issue de l'armée russe, Appairées

www.thomann.de

TAD RT272 Tubes EL84 Cz Pair

Set de 2 lampes

www.thomann.de

I should mention that i'm using the Blues Junior at low volume in my appartment : Volume between 2 and 3/12 and Master volume also between 2 or 3. I don't use it for "natural" tube distortion, or anything like that.

Edit : I see they also have some TAD EL84-STR RedBase. But they arent coming in pair. Is it very important to get a pair ?

TAD EL84-STR Redbase

Lampe d'amplification EL84 Combine les meilleures caractéristiques des célèbres EL84-CZ et EL84M, Très grande fiabilité, N° TAD: RT871 Remarque: En raison du diamètre de 22,5 mm, les TAD EL84-STR ne conviennent pas pour les anciens amplis Marshall...

www.thomann.de

Every observation and suggestions are welcome !

 

[Giorfida]

Hello,

I need a new spare set of tubes for my Blues Junior 3 : 3x ECC82 and 2x EL84

The original tubes are getting fried one by one after 9 or 10 years of service. EL84 were GT Groove Tubes, the ECC82 are still fine so far, but i guess after 10 years they will also fry sometime soon.

Looking at thomann's products, i wonder if it's worth the extra 20 euros to buy the RT372 ?

They say it has a longer lifespan, is it significantly better than RT272 ?

I guess i don't mind paying a little more money, if it means several additionnal years of use.

TAD RT372 Tubes EL84M Pair

Paire de lampes La plus longue durée de vie sur le marché, issue de l'armée russe, Appairées

www.thomann.de

TAD RT272 Tubes EL84 Cz Pair

Set de 2 lampes

www.thomann.de

I should mention that i'm using the Blues Junior at low volume in my appartment : Volume between 2 and 3/12 and Master volume also between 2 or 3. I don't use it for "natural" tube distortion, or anything like that.

Edit : I see they also have some TAD EL84-STR RedBase. But they arent coming in pair. Is it very important to get a pair ?

TAD EL84-STR Redbase

Lampe d'amplification EL84 Combine les meilleures caractéristiques des célèbres EL84-CZ et EL84M, Très grande fiabilité, N° TAD: RT871 Remarque: En raison du diamètre de 22,5 mm, les TAD EL84-STR ne conviennent pas pour les anciens amplis Marshall...

www.thomann.de

Every observation and suggestions are welcome !

To be honest, the way Fender designed the BJ, you could crank it to 10, but you’d throw either the phase inverter and/or the solid state loop/verb is into all out square wave fuzz long before you’d get the output tubes to start clipping.

IMHO,I don’t think it would matter which current production tube you picked as they are all pretty similar. What your amp needs is the bias cooler a bit and likely bigger screen stoppers- then you’ll never have to worry about power tube life again. Simply put Fender likes to run these tubes at higher than spec voltage, which you can get away with if you are kind to your screens, and keep the bias conservative

 

[pingpongcomputer]

The new production tung sol 7189s are great for long life in el84 amps at much better than nos 7189 prices. They are higher headroom so that could change the sound, but they've been very reliable tubes for me in guitar and hifi amps

 

[eh là bas ma]

Thanks for your replies !

What your amp needs is the bias cooler a bit and likely bigger screen stoppers- then you’ll never have to worry about power tube life again. Simply put Fender likes to run these tubes at higher than spec voltage, which you can get away with if you are kind to your screens, and keep the bias conservative

Interesting. I'm not sure i would be able to do that, though. I've never touched an amp's circuitry before, so i guess i'll leave it as it is, until the day i know a bit more about it. That's my one and only tube amp, so i guess i'd need some old cheap tube amp that i don't care about, to learn and do some trials, before modifying my precious amp.

What's the point with tube pairs ? Is it all about getting the best possible tube sound when it's used at very high volume ? Does it impact their life span if i buy two separate tubes with the same brand and designation ?

Let's remember i will probably never use that Blues Junior at high volume, i have a poor sound insulation in my appartment, and something tells me it will always be the case in my humble life. I like living in big cities, i don't think i will ever be able to afford a place with good sound insulation. So maybe that low-volume factor can impact the tube selection ?

 

[pbrommer]

Thanks for your replies !



Interesting. I'm not sure i would be able to do that, though. I've never touched an amp's circuitry before, so i guess i'll leave it as it is, until the day i know a bit more about it. That's my one and only tube amp, so i guess i'd need some old cheap tube amp that i don't care about, to learn and do some trials, before modifying my precious amp.

What's the point with tube pairs ? Is it all about getting the best possible tube sound when it's used at very high volume ? Does it impact their life span if i buy two separate tubes with the same brand and designation ?

Let's remember i will probably never use that Blues Junior at high volume, i have a poor sound insulation in my appartment, and something tells me it will always be the case in my humble life. I like living in big cities, i don't think i will ever be able to afford a place with good sound insulation. So maybe that low-volume factor can impact the tube selection ?

Bias isn't too hard. Usually most up the cathode resistor to the EL84 pair. Usually they set it at 100 ohms/5W square cermet resistor. Blues Jr. need I think 150-180 ohm to be happy. The change is pretty straightforward. If I can gut a Valve Jr., wire it up, and not burn down an apartment, then you can too.

Tube pairs are important, but not super duper critical. Guitar amplifiers act way different than higfi and sometimes drift a bit: 5-10mA difference is common. Sometimes the bit of imbalance is good sounding to your ear.

Now, realize I'm pulling the numbers off the top of my head and I can't remember everything - I'm not knee deep into amps as much. Hope this helps?

 

[hamerfan]

There are kits from Fromel electronics to mod amp. These are bit spendy, but you learn a lot about amps and do your mod in a safe way. Great for doing the first time.

Fender Blues Junior Modifications

Unleash the tone of your Blues JR with these modifications from Fromel Electronics! From the factory, this pint size wonder has a lot of potential, but with some select Fromel tweaks this amp can stand toe-to-toe with some of the finest boutique amps on the market. After the mod, the amp boasts...

fromelelectronics.com