Submitted by ZevireTees t3_zzl9e0 in headphones
Comments
ZevireTees OP t1_j2cak68 wrote
oh wow!
pongpaktecha t1_j2ckxwe wrote
They can also be hooked up in parallel with out too much issues since the paralleled impedance will still be plenty high
HedgehogRoutine2695 t1_j2d75hq wrote
now how tf does that work
florinandrei t1_j2ff0l2 wrote
It only works when the signal is very strong, and it's an AM thing.
I've done this as a kid. There was a powerful AM station nearby, enough signal for listening in headphones. Using a huge wire antenna, good ground connection, and an output transformer, I was actually able to feed just barely enough signal in a small speaker. Placing the speaker in a small transistor radio box (like a DIY speaker box) made it audible in my room at a soft, but decent level.
There were no batteries in the schematic. All the energy came from the radio station. Since only one strong station was in the area, I didn't even need an LC frequency filter - a germanium diode was the only real component besides the headphones (or speaker + transformer). One side of a germanium transistor also works instead of a diode. Silicon diodes / transistors don't work.
The signal was plenty for comfortable listening in headphones. I was able to even use metallic rain gutters as an antenna, and my hand as a "ground connection" and it still worked okay. I could impress my friends by touching one wire to the rain gutters, and AM radio would play in the headphones.
High impedance headphones worked better. For the speaker, the transformer basically was just an impedance adapter - speakers have low impedance, but the schematic required high impedance for best results.
Here's the schematic for headphones:
Replace the headphones with transformer + speaker if you wish, but don't expect a lot of volume even in the best case.
If there is no strong AM station nearby, then it will not work at all.
General info and more complex schematics:
AffectionateGrowth25 t1_j2fttpu wrote
Woah. This is good stuff
SuperTinkerer t1_j2e59oo wrote
Like son goku's spirit bomb...extracting tons of energy from the air..haha,does not work like that...
[deleted] t1_j2dox9f wrote
[deleted]
audiochef68 t1_j2ck4vx wrote
Are these from an electric chair ?
Efficient_Truth_9461 t1_j2fcoki wrote
They used to play kid rock during executions, but it was deemed cruel and unusual
Suspicious_Life_6846 t1_j2cv3i9 wrote
Crinacle: ๐ Dongle ๐
cirrusblau t1_j2dy8o4 wrote
Reddit: No amp needed
FerdinandTheSecond t1_j2e2ghd wrote
You just need one microwatt for them to sound, anything else is waste - graph guys
Efficient_Truth_9461 t1_j2fd1dk wrote
This subreddit would drive their cars with that thing if there was a port
sverek t1_j2c9xdh wrote
Dongle will drive it just fine.
ZevireTees OP t1_j2ca3y7 wrote
I won't buy these. They need too much work to look good. The would be cool to play with.
f3llyn t1_j2cnbux wrote
moonra_zk t1_j2f1hl2 wrote
Knew what it was before I clicked, simply the best restoration channel on YouTube.
f3llyn t1_j2f2lys wrote
Yes, his work is impressive.
AM5T3R6AMM3R t1_j2d8cqz wrote
What a pro!!!
Cassiopeat t1_j2e3ugd wrote
Omg
Ticonderogue t1_j2d7zux wrote
All beat up makes a statement. If these headphones could talk. I'd buy them for the right price.
YourMother0HP t1_j2d0yz1 wrote
Even your topping a30 will drive it just fine
sverek t1_j2d6obi wrote
Topping will burn these headphones with hatred for the free world.
ZevireTees OP t1_j2c9p8w wrote
I found these headphones online, and I don't understand how you would be able to run 1500 ohm headphones. I wanted to find some headphones that looked kind of like these but I want to see of someone can mod the with new drivers. I came across these and was stunned because I had not seen over 600 ohms.
blargh4 t1_j2cbpxm wrote
> I don't understand how you would be able to run 1500 ohm headphones
depends entirely on their sensitivity... possibly very easily.
Half-White-Mexican t1_j2ccb16 wrote
I converted a kilo-ohm military aviation/tank headset and it got more than enough power from my TA-30. You can drive them with any amp that provides enough power.
Berny-Aver95 t1_j2chqx3 wrote
And how do they sound?
Half-White-Mexican t1_j2cnsm9 wrote
All mids. Great for radioing your comrades, awful for everything else.
I was able to EQ them and they sound half decent, but still don't have all that much technical ability.
oratory1990 t1_j2d8942 wrote
> You can drive them with any amp that provides enough power.
With a load impedance that high you'll mostly be concerned about providing sufficient voltage. Current draw (and hence power) won't be high due to the high load impedance.
Cartella t1_j2cxua6 wrote
Assuming the same efficiency, the difference in sensitivity of a 1500 ohm headphone and a 600 ohm one is 4 dB, which is probably less than you think. Or almost 8 dB from a 250 ohm one.
audiophile_lurker t1_j2dxsb9 wrote
Electrostatic headphones have impedances to the tune of 100,000 ohms. 1500 ohm is not that big a deal as long as long as they are either fairly sensitive (which is probably the case for crystal radio headphones), or you got a high voltage amplifier (do not need much current at this point).
Shlushii t1_j2eh4xc wrote
Hotwire it right into the back of a serious speaker amp
ItDoesntSeemToBeWrkn t1_j2cy4m0 wrote
ohm my god
Xypton t1_j2csz6e wrote
Fun fact: BA drivers can be of arbitrary impedance, even something like 20Kฮฉ is possible, as this saves power for application in hearing aids
sandtymanty t1_j2cyoxg wrote
I love these 16th century headphones.
Houstonb2020 t1_j2f62e1 wrote
I see your 1.5k ohms and present my 10k ohm headphones
iAyushRaj t1_j2cp4iq wrote
Apple Dongle with an iPhone ๐
Pr3ssF2PayR3sp3c7 t1_j2ddj9n wrote
My Sennheiser HD 414 has 2000 Ohms. But they are surprisingly easy to drive. I even get them to a listenable level with my phone
TheDogFather t1_j2dytfh wrote
Endgame right there.
Overall_Falcon_8526 t1_j2er2o8 wrote
Ask not what your headphones can do for you - Ask what you can do for your headphones.
matefeedkillrepeat_8 t1_j2dvjor wrote
Look heavy
excellent_alt6969 t1_j2dy902 wrote
i dont know about these headphones but they better sound MAJESTICALL for me to run out and buy another fucking amp to drive these fuckers
dangit1590 t1_j2erg1t wrote
Damn these the jfk edition
emceejc88 t1_j2f4262 wrote
I thought it was some kind of virginity lock at firstโฆ
PrimitiveMeat t1_j2fg2ub wrote
Probably still better than the Gen4 A50 Astros
Doc-85 t1_j2em9kr wrote
Holy shit, you need a whole electric substation to power these or a small scale nuclear reactor!
SupOrSalad t1_j2cahfk wrote
The funny thing is a lot of these old headphones that are between 1000-4000ohms are meant to be run on crystal radios. No external power, just the energy in the radio waves themselves are what supplies power to the radio and headphones