[AnakChan]

Now that I have the Susvara, I kinda regret getting rid of my Theorem 720 ‘cos it was really powerful for a portable DAC/Amp. I’m curious if the Theorem can drive the Susvara. As a comparison, the Topaz WA11 can, so I’m not quick to dismiss that portable amps can’t drive an inefficient headphone.

 

[nephilim32]

Still loving it.

 

[fishda30]

How to replace the battery of the theorem? I opened mine to remove the battery. Problem is the battery is glued to the board. I'm afraid to pry it from the board as the board might break.

Ps. Can i use any 3. 7v battery?

 

[ANDEROAN]

How to replace the battery of the theorem? I opened mine to remove the battery. Problem is the battery is glued to the board. I'm afraid to pry it from the board as the board might break.

Ps. Can i use any 3. 7v battery?

um wish I knew, usually it is only 2 faced tape? and just a little stern pulling will do the trick, but if it is glued, ouch, then the only way to replace the battery is to buy my Theorem for $800,000 bu wa hahaha, just kidding some halloween humor, or unless...? lol,

but hopefully someone can help, I can take mine apart and see what I can see? I have ripped batteries out of amps before, probably can't help but...um you can ask Todd the vinyl junkie at TTVJ audio https://www.ttvjaudio.com/, they sold a ton of Cypher Lab gear back in the day! it is awesome that they are still around,

 

[nephilim32]

um wish I knew, usually it is only 2 faced tape? and just a little stern pulling will do the trick, but if it is glued, ouch, then the only way to replace the battery is to buy my Theorem for $800,000 bu wa hahaha, just kidding some halloween humor, or unless...? lol,

but hopefully someone can help, I can take mine apart and see what I can see? I have ripped batteries out of amps before, probably can't help but...um you can ask Todd the vinyl junkie at TTVJ audio https://www.ttvjaudio.com/, they sold a ton of Cypher Lab gear back in the day! it is awesome that they are still around,

hey cool man! Let me know what you come up with. I’d like to learn as well. I have the algorithm Trio tube amp from CL and I find it so awesome that I ended up buying 2 extra batteries and 2 extra 6111 tubes from David maudlin.
one day I will have to replace those parts so any knowledge you can share would be so greatly appreciated to this head-Fi man.

 

[fishda30]

Still haven't attempted to remove the batteries. I'll take pictures later. Do you think it's ok to just cut off the cables going to the battery and just plug in the charger? I'm planning to use it as a desktop dac/amp instead.

 

[fishda30]

 

[fishda30]

Internal pics of my theorem. Do you think i can just cut off the battery connection and use the charger to power the unit?

 

[ANDEROAN]

if your going to use it as a desktop amp, ditching the battery would be nice, it is HUGE! I would think it should work by cutting the battery? and easing/prying it away from the double faced tape, if your careful it should be easy enough, but that is just my guess, did you try to get ahold of Todd from TTVJ? or try PM'ing someone from the DIY forum in the misc. category as to what you may be able to do whith out having catastrophic failure ? should be a simple ? for someone that has some basic understanding, it would be if the current is tied in with the battery flow? into the battery, and then out to the board? but the power goes into the board first, and then to the battery, so my guess is you should be able to cut the wires? but a very limited guess?

but rule of thumb for some amps is to not use it while charging it, because it can over heat the battery? but since the battery is dead, that may not apply?

 

[ANDEROAN]

hey cool man! Let me know what you come up with. I’d like to learn as well. I have the algorithm Trio tube amp from CL and I find it so awesome that I ended up buying 2 extra batteries and 2 extra 6111 tubes from David maudlin.
one day I will have to replace those parts so any knowledge you can share would be so greatly appreciated to this head-Fi man.

yeppers, I have duped several pieces of gear that I liked alot, when did you get the batteries and tubes from David Maudlin? and who is David Maudlin?

 

[fishda30]

$5 on battery and $4 on labor. Gets the job done.

 

[ronnietan1218]

Hi everyone, got some questions wanted to ask :

1. Do anyone know how to replace the battery of the CypherLabs Theorem 720? Can show me step by step to disassembly and replace it? Currently I'm only able to unscrewed the screws at outside but unable to remove the volume knob, I'm not sure how to disassembly the volume knob as there's no any information to remove the knob in order to show the internal board and the battery.
2. Can know is there any battery spare parts that I can buy from to replace it? Like is there any requirement for the battery to work on this DAC?
3. When I plugged in and power on, the LED is kept changing colors even when volume knob is turned off or on, what does it mean?

Really appreciate if someone can help me, thank you.

 

[fishda30]

I had mine replaced by a local technician. He wrapped 3 18650 batteries together and used the old power cables to install them. He soldered it with lead.

 

[ronnietan1218]

I had mine replaced by a local technician. He wrapped 3 18650 batteries together and used the old power cables to install them. He soldered it with lead.

Noted, thank you for the information. Want to know what type of 18650 batteries do they used? Button top or Flat top? And usually this kind of replacement can done by any technician right? Also you managed to remove the volume knob to open the internal, mine unable. Can show me how to remove it?

 

[fishda30]

Noted, thank you for the information. Want to know what type of 18650 batteries do they used? Button top or Flat top? And usually this kind of replacement can done by any technician right? Also you managed to remove the volume knob to open the internal, mine unable. Can show me how to remove it?

I just removed all the screws and pushed the amp. The volume knob also has a screw. Just take it out.