Attention DIY gurus. SPEAKER OUT to power Sennheiser HD580s Fatman itube red-i ? Thanks
Jul 16, 2009 at 4:56 PM Thread Starter Post #1 of 13


100+ Head-Fier
Mar 13, 2006
I recently purchased a Fatman I-red itube: Link: Fatman iTube Red-i with Speakers

This amp does not provide a headphone jack and only really has speaker outputs. Is there anyway to rewire my Sennheiser HD580 so that I can power them with this amp? Specifically, i was wondering if there was an adapter to connect my headphones to the speaker output?

Is this even advisable given the specs of the amp?

* Power Output: 25Wx2
* Frequency Response: 20Hz - 20KHz (±1.5Db)
* Harmonic Distortion: ≤0.5%
* Signal-To-Noise Ratio: ≥86Db
* Input Impedance: 100KΩ
* Output Impedance: 4Ω, 8Ω
* Valve Type: 2x6N1(ECC85)
* 1x6E2(EM87)
* Power Supply: AC100~120V/50~60Hz, AC220~240V/50~60Hz
* Dimensions: Amp: 450x220x210 mm ( WxHxD), Speaker: 330x315x210 mm ( WxHxD)
* Weight: Amp: 5.8kgs, Speaker: 6.8kgs

I am a total noobie to DIY projects so any part numbers would be greatly appreciated. I don't know where to get the cables to actually connect my headphone male out 2.5mm to the speaker out.

Jul 16, 2009 at 5:02 PM Post #2 of 13
Just make an adapter...

Buy a 1/4 inch stereo jack and wire it up with some speaker cabling with separate ground wires for the two channels and hook it up the amplifier output and plug in your headphones.

I use my Sansui AU-217 with the Wharfedale ID1s using such an adapter..
Jul 16, 2009 at 5:09 PM Post #3 of 13
So the connection would be:

headphone--->1/4 inch stereo jack---->speaker cabling---->hook into speaker output?

I don't really understand what you mean by "separate ground wire"

Sorry for the total lack of knowledge. I have been hovering over google for a number of hours and have yet to find an answer =(

Jul 16, 2009 at 5:17 PM Post #4 of 13
yep..that's the chain.

Basically take 4 pieces of wire. one each for the signal and ground pairs of each channel. Solder the ground wires together to the common ground pin on the headphone jack.

Out the other end of the jack you will have 4 wires hanging off now..2 pairs of signal and ground. Hook those up accordingly to your speaker amp and you are set to go.
Jul 16, 2009 at 5:25 PM Post #5 of 13
Thanks've been a big help.

Quick question(s). I have never puchased quality speaker cable before.

1. Do I have to purchase all 4 cables or can i just cut a longer piece?

2. Does each cable come with a ground wire attached or is that something else i have to order?

3. When soldering the ground into the headphone jack, i'm guessing that you're refrerring to*1/4" Stereo In-Line Jack Plastic | 1/4 jack phone plug inline jack 1/4" plug audio connector TRS connector Does this have a place to solder cables onto? It looks to me just look a piece of plastic with no metal connections?

And finally =)

4. Do you have one that you would recommend?

Thanks man
Jul 16, 2009 at 5:30 PM Post #6 of 13
1> Just cut out a longer piece..radioshack speaker cables are good enough but if you want to go gaga over the kind of cable you want to use, then that is your call

2> Most speaker cables are paired so yes.

3> yes, you screw the plastic back off the jack to reveal the terminals to solder th e wires onto.

4> am using the same one I linked you to and it works just fine. However, if you want the locking type then that's available as well here
Jul 16, 2009 at 7:20 PM Post #10 of 13

Originally Posted by mplee79 /img/forum/go_quote.gif
If i get a line level converter, will my headphones still receive any power from the amp (will this be sufficient to power my hd580)*Audioplex SPKCNV Speaker Level To Line Level Converter | speaker jacks speaker jack rca jacks rca jack rca converter rca power converter power amplifier power line level converter line level line converter jacks jack ev converters

Don't use a line level converter. The impedance and current handling are wrong. A line adapter assumes it's outputting to a very large impedance, which means very low current. At best, you'll just break the adapter.

Use the article above to build something custom. Add a generous amount to the power handling numbers when you order parts, if the article doesn't already account for that. Doubling the power rating isn't a bad place to start. More is better here. You don't want to heat the resistors too much, it'll just cause them to drift and shorten their life.
Jul 19, 2009 at 7:08 AM Post #11 of 13
Jul 19, 2009 at 3:41 PM Post #12 of 13
The ProCo HJ-4P Headphone Junction box is exactly what's in the article on westhost. The thing is, it's generic, so it won't be the best match for your particular system. Also, the inputs are XLR, so you'll need to get a connector and wire it to your speakers.

Here's what bothers me. In order to match the impedance, you'll need to open it up and change the values of resistors and possibly the potentiometer. If you don't do that, you're kind of taking chances on the load the amp sees. I don't know whether the amp will be happy with that kind of load. In general, most amps would be just fine, but there are some that would have problems.
Jul 20, 2009 at 4:20 AM Post #13 of 13
First thing, don't hook it up through the 1/4" jack. You need a balanced cable or something that has grounds for individual channels. I don't know what the detachable cable looks like, but if possible try wiring the HD580 up with speaker wire. Speaker amps don't like their grounds to be connected. It could ruin the amp (I believe).

Shouldn't they work fine just hooked up to the high-level outputs? It is going into 300ohms... Just make sure to start out with the volume all the way down

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