Undressed Beyerdynamics DT 931

[moongate]

Hello together,

I just had to open my DT 931 to reverse the inner foam pads. They came out towards my ears with the time and touched them lately so I decided to flip them over.

I thought I take some pictures while the cans are open for everybodies interest:

´
Looking as big as everything does I really don´t know why bass is so flat at time?

Ciaoi

Moongate

 

[sgrossklass]

Quote:

Originally Posted by moongate Looking as big as everything does I really don´t know why bass is so flat at time?

What kind of output impedance does your amp have? These older Beyers seem to be optimized for higher ones, 120 ohm at least.

Nice pics btw.

 

[moongate]

Quote:

Originally Posted by sgrossklass What kind of output impedance does your amp have? These older Beyers seem to be optimized for higher ones, 120 ohm at least. Nice pics btw.

I use the HEED can amp.

The CanAmp is a two-stage amplifier. While the first - voltage gain - stage is based on an integrated circuit of the highest audio pedigree, the second - power gain - stage is a single-ended, pure Class-A amplifier. It enables the CanAmp to drive virtually any headphones from 8 ohms up to 600 ohms. As its output power (at 8 ohm) is nearly 1W, the CanAmp could drive even a high-sensitivity loudspeaker!

http://www.heedaudio.hu/

I bought this amp on purpose (I know it is hardly known by now) because I´m planning to buy the 2006 Beyerdynamic DT 990 with the 600 ohm mod.

I´m really looking forward to it.

But anyway I´m not talking about the DT 931 having no bass - I´m talking about the DT 931 compared to everything else that we love. The weekpoint of the DT 931 is truly the lower sector as well as the mids when compared to the HD 650. On the other hand side user report that the DT 931 is one of the brightest headphones they ever listened to while the HD 650 is sounding veiled. That is why people are replacing the HD 650´s foam lately.

 

[sgrossklass]

If the amp can drive 8 ohm loudspeakers, it most likely has a low output impedance in the single-digit region. That would be good for low-impedance cans or anything that likes a high damping factor, but DT931s were probably tuned with ordinary integrated power amp outputs in mind, which typically have output impedances ranging from 100 to 470 ohm.

 

[Serge44]

These cans aren't bassy at all. But nevertheless I like them for some kind of music: ethnic, jazz, classic. They are not suitable for rock and pop. Too sibiliant for me and shy bass.

 

[moongate]

Quote:

Originally Posted by sgrossklass If the amp can drive 8 ohm loudspeakers, it most likely has a low output impedance in the single-digit region. That would be good for low-impedance cans or anything that likes a high damping factor, but DT931s were probably tuned with ordinary integrated power amp outputs in mind, which typically have output impedances ranging from 100 to 470 ohm.

Hello sgrossklass,

this can amp is especially designed for headphones of the 600 ohm region. You can read that in my last post. That was the only reason why I chose this one over the other candidates.

It shure has a high output impedance headphone jack.

BUT, you can also use it as an amp/preamp for speakers, but in this case there is a slight difference - you use the jacks at the back of the amp and those are a different matter.

And just as Serge44 is saying - this is not a setup question because the nature of the DT 931 is having a shy bass.

 

[Andresin]

You should clean those velour pads while you're at it. I recently opened my DT531's to clean 'em out. Just use some soap and hot water. Works great, but takes a long time to dry.

Thx for the nice pics

.

 

[moongate]

Quote:

Originally Posted by Andresin You should clean those velour pads while you're at it. I recently opened my DT531's to clean 'em out. Just use some soap and hot water. Works great, but takes a long time to dry. Thx for the nice pics .

I contacted Beyer 2 days ago to have those pads replaced. I also need a new left plastic cup because it has a slight crack where the cable comes out.

Since I want to add the DT 931 to my hall of fame he needs to be in perfect condition. Cleaning the pads is one thing but the foam inside them has flatened out so the cups are too close to my ears anyway. I have the cans for about 8 years now. bought them around 1997!

 

[Andresin]

Quote:

Originally Posted by moongate I contacted Beyer 2 days ago to have those pads replaced. I also need a new left plastic cup because it has a slight crack where the cable comes out. Since I want to add the DT 931 to my hall of fame he needs to be in perfect condition. Cleaning the pads is one thing but the foam inside them has flatened out so the cups are too close to my ears anyway. I have the cans for about 8 years now. bought them around 1997!

Yes they do flatten out

. I compared my 4 year old DT531 to som new DT880's, and the pads where very different. I might have to get some new ones as well

.

 

[pedxing]

How do you dissassemble the DT-931?

 

[kuma]

Quote:

On the other hand side user report that the DT 931 is one of the brightest headphones they ever listened to while the HD 650 is sounding veiled.

Really?

They don't sound bright at all in my rig.
Nothing else they lack in the clarity and trnasients of the RS1/MP.

Nice cans, tho. I much prefer these over the DT880.

 

[Anders]

moongate, I am sure that your amp is good at driving 600 ohm headphones. The question is what amplifier impedance is best for driving DT931 and here there is an advantage of a higher amplifer impedance. DT931 sounds less bright and has more bass from the 120 ohm output from a Corda amplifier from Meier Audio than it has from the 0 ohm output on the same amp. It is also possible to make an external headphone adapter with a resistor. This is described at Meier Audios homepage.

 

[machead]

Quote:

Originally Posted by Anders DT931 sounds less bright and has more bass from the 120 ohm output from a Corda amplifier from Meier Audio than it has from the 0 ohm output on the same amp. It is also possible to make an external headphone adapter with a resistor. This is described at Meier Audios homepage.

I can personally vouch for the truth of that statement! The DT931 needs a high impedance amplifier output to sound its best. Jan Meier supplies a 120 ohm adapter for his Porta Corda amplifier -- if you contact him via his web site , I'm sure he'd be happy to sell you one.

 

[Andresin]

Quote:

Originally Posted by pedxing How do you dissassemble the DT-931?

You take the pads off, gently pushing them outward. Then there is a plastic ring that they where attached to that you need to pull out, and another plastic ring holding the foam covering the drivers that you need to pry loose. I can't remember right now which of the plastic rings came first

. Just be gentle and you'll probably be allright. It's very easy to disassemble/assemble them. ;y experience is from the DT531 though. I'm sure it's the same

.

 

[moongate]

Quote:

Originally Posted by pedxing How do you dissassemble the DT-931?

First you grad under the velour with your fingers and pull it out between the
plastic can and the inner plastic ring. when the black part that is holding the velour is coming out a bit you can stick a thin knife inbetween.turn it and the inner plastik ring snapsout. now put the velours back on that ring.

the rest is open now as can be seen on my pics