[Asterisk3095]

Most no longer made. Life depends on design and quality of tube construction.

ah I see... well that's unfortunate. someday there won't be any more tubes....

 

[bagwell359]

How many watts are the resistors? 1w, 3w?

I have a valve amplifier very similar to the bottlehead, 6sa7g rca and 6sn7wgta sylvania brown, I opened it and I see that it has a speed ball (I didn't make it), I wanted to modify it so that it sounds better in the beyerdynamic dt880 600ohm, I notice it lacks power, mainly bass, the superlux 681 (modified, cable and casing) superlux hd330 150ohm (cable mod) works very well, with multitester it gives me the output at maximum volume voltage 3.w (varies according to the music and the moment in it is reproduced) with peaks of 5.5w in both channels and 10.00 kohm I leave some images in case you can give me some advice, what to modify

Speedball?

capacitor 220uf 160v siemens in the end towards the jack socket

Resistors in coffins? Do you test values? Lots of naked wire. I jacket every bare wire in Teflon. Hate shorts except outside. I do like bypassing caps. That directional cap attached the 150 uf resistor would be tough to dussasemble.

 

[bagwell359]

ah I see... well that's unfortunate. someday there won't be any more tubes....

Nah somebody will sell you NOS tubes or make new tubes if your wallet can handle it.

I have 1 very rare very great tube should last about 10x less than its life span which at age 65 is all I will need

 

[jonathan c]

ah I see... well that's unfortunate. someday there won't be any more tubes....

There will be tubes at a price that meets the demand. Whether a particular buyer can ‘stomach’ that price, well…

 

[KonanAtlante]

Resistors in coffins? Do you test values? Lots of naked wire. I jacket every bare wire in Teflon. Hate shorts except outside. I do like bypassing caps. That directional cap attached the 150 uf resistor would be tough to dussasemble.

I only tested the stripped jack output without any headphone load
complete old image, the blue cable that is seen from the xlr input to the alps potentiometer and from the siemens capacitor to the jack output, I changed it to low impedance 22awg roxtone, with this I eliminated radio noise that it had despite the insulation it has and I won a 25% volume approx, I also removed a led light diode that it had indicating the power on, according to what I read, this diode consumed me between 23 to 53 mw, the led diode had a rectifier diode and a resistor, when I removed them together with the diode led sound got very dirty especially the broken bass, I don't know their values, I reconnected them without the led diode and the sound came back clean and noiseless

 

[Asterisk3095]

There will be tubes at a price that meets the demand. Whether a particular buyer can ‘stomach’ that price, well…

well yeah that makes sense. not going to be spending hundreds on rare tubes (yet) so i should be fine in that regard

 

[Galapac]

ah I see... well that's unfortunate. someday there won't be any more tubes....

There will be tubes, especially those that are more popular, just not the old NOS desired ones that most favor for their superior designs and materials.
There are companies today that make new tubes in Russia, China, Slovakia, and a few boutique tube manufacturers in other countries that make real high end tubes like the 300B for $$$$.

 

[bagwell359]

I only tested the stripped jack output without any headphone load
complete old image, the blue cable that is seen from the xlr input to the alps potentiometer and from the siemens capacitor to the jack output, I changed it to low impedance 22awg roxtone, with this I eliminated radio noise that it had despite the insulation it has and I won a 25% volume approx, I also removed a led light diode that it had indicating the power on, according to what I read, this diode consumed me between 23 to 53 mw, the led diode had a rectifier diode and a resistor, when I removed them together with the diode led sound got very dirty especially the broken bass, I don't know their values, I reconnected them without the led diode and the sound came back clean and noiseless

That's quite nice. Good job.

 

[cddc]

As someone new to tubes, how many hours does a tube typically have for its lifetime? Furthermore, are there any popular tubes that are still in production? It makes me worried that I might like a certain tube, but when it runs out of life there won't be any more I can get since they won't be in production.

Normally new or NOS tubes last 5k - 10k hours under normal load, but in Crack they are lightly loaded, so they will last even longer. So there is no need to worry about tube lifetime.

Furthermore, tubes used in Crack are easy to find and their supply is abundant...I mean really really abundant....

 

[Asterisk3095]

Normally new or NOS tubes last 5k - 10k hours under normal load, but in Crack they are lightly loaded, so they will last even longer. So there is no need to worry about tube lifetime.

Furthermore, tubes used in Crack are easy to find and their supply is abundant...I mean really really abundant....

I see! Many thanks. Glad to know that tubes are still so plentiful. I guess I was worried because I heard people saying there is a shortage due to the ongoing war in Ukraine/Russia

 

[cddc]

I see! Many thanks. Glad to know that tubes are still so plentiful. I guess I was worried because I heard people saying there is a shortage due to the ongoing war in Ukraine/Russia

The war only impacts Russian new production tubes, but those new production tubes can hardly compete with NOS tubes. There are tons of NOS 6080/6AS7G/12AU7/6SN7 tubes out there, so no worries.

 

[bagwell359]

Normally new or NOS tubes last 5k - 10k hours under normal load, but in Crack they are lightly loaded, so they will last even longer. So there is no need to worry about tube lifetime.

Furthermore, tubes used in Crack are easy to find and their supply is abundant...I mean really really abundant....

Unless one uses an alternate driver tube like the EC80CC. Also finding a standout 6080 type is difficult.

Also nobody mentioned the plethora of bogus NOS tubes available - on x bay and other places.

Some of the newer tubes from Czech, Russia, and China are unlistenable vs the same types from pre 1970 Europe and the US

Overall you can wend your way - just stick with the tubes you get with the BHC. It's when you step into the depths that the churn can be quite wild.

 

[bagwell359]

Chatham 2399 with Telefunken E80CC about 5 mins ago .... good stuffs for sure.

Fairly similar

 

[cddc]

Unless one uses an alternate driver tube like the EC80CC. Also finding a standout 6080 type is difficult.

Also nobody mentioned the plethora of bogus NOS tubes available - on x bay and other places.

Some of the newer tubes from Czech, Russia, and China are unlistenable vs the same types from pre 1970 Europe and the US

Overall you can wend your way - just stick with the tubes you get with the BHC. It's when you step into the depths that the churn can be quite wild.

Yeah, I suppose it would be difficult to find a tube with the signature from her majesty the queen, but the 12AU7 and 6080 NOS tubes that come with the Crack kit can easily be found $5 apiece.

 

[tomb]

<snip>

Thanks for the thorough explanation tomb! I understand better now. However, did you mean "Replace the electrolytic cap with a film cap and you may be increasing the power supply noise, not improving it."? Based on what you said about film caps having nothing to do with removing ripple and hum, that makes sense -- was that a mix-up?

So, my understanding now is that electrolytics are important in a PS to remove ripple and hum, so replacing them with film outright is not a great idea -- but bypassing with film is good as it can add a bit of smoothness to the de-rippled and de-hummed signal. Is that fair to say?

Sorry for the super-delayed response, but someone just liked my post that you are referencing.

So, in answer to the question, "Based on what you said about film caps having nothing to do with removing ripple and hum, that makes sense -- was that a mix-up?" - there are more forms of noise from a power supply than just hum and ripple.

I'll just go out on a limb here and make the sweeping statement: Most switching power supplies have little to no issue with ripple and hum. Yet, most of them in a high-fidelity audio application sound like crap. This is because switching power supplies introduce high-frequency trash into the power circuit. A lot of this is beyond the audio limits of 20kHz, but harmonics cause the effects to be heard much lower down, well into the audio band. Yes, there are some mfrs who claim their switching supplies are completely free of such noise, but that's a highly debatable topic, mostly because it almost always centers around whether you can hear it. What one mfr may claim is inaudible may be clearly audible with our high-performance headphone setups.

The specific reference I was making to film caps is that film caps in a power supply are there (one of many reasons) to reduce the high-frequency hash. Even if the power supply is not a "switching" type, rectifiers themselves are switching all the time in the absolutely necessary conversion of AC to DC. Sometimes film caps are placed directly across the leads of rectifiers to reduce this switching noise. So, yes - I stated that if you replace a film cap with an electrolytic in a power supply you may increase the noise, not reduce it. I didn't say that particular noise was hum and ripple. An electrolytic capacitor is very useful for reducing hum and ripple, but high frequency noise? No.