[jpelg]

Quote:

Originally Posted by jpelg /img/forum/go_quote.gif The big question how the Panny's digital amp would handle the load in terms of FR shifts. The results may be different for low-impedance (<100 ohm) cans vs. the higher-impedance Senns, as well.

Quote:

Originally Posted by scompton /img/forum/go_quote.gif Connecting headphones to a T amp's speaker terminals doesn't work, at list for the Sonic Impact T amps. I'm not sure about others. There have been a couple of threads with links to DIY sites that talk about what's going on when you do it. It has something to do with some type of filtering that requires separate grounds.

Yes, I can corroborate that using a digital amp with any common-ground connection does not work. I have an ASL UHC device that is a speaker amp-to-headphone jack transformer device, and it did not work with my JVC digital-amp receiver.

The other issue, as you allude to, is the frequency shift that apparently occurs when connecting digital amps to non-optimized loads. Usually a speaker amp is designed for 4 or 8-ohm loads. Digital amps apparently have a filter that adjusts their frequency response based on this assumption. I don't completely understand the technical details, but this is what I have gleaned from asking similiar questions. Basically, connecting a different load than the designer intended causes this shift.

However, this does not necessarily mean that something will sound bad, assuming the separate ground connection thing is properly addressed. The AKG K1000's are 120-ohm, and they sounded terrific to me when connected to my old digital amp. Maybe there was a frequency shift happening, but it sounded great to me *shrug*. Imo, the value of the latest digital amps (price :: performance ratio) is undeniable.

I just never tried connecting regular headphones to it with separate ground wiring. Sennheiser HD600's are cabled with separate ground wires at the driver-end that meet up at the 1/4" plug. It would be a simple matter of modifying a stock cable (or a second cable) by cutting off the 1/4" plug and wiring the four wires to the speaker taps. Grado & top AKG cables are similiar, albeit hardwired.

Most Ultrasone's are wired with a common ground. But I'm considering having mine rewired to each driver separately for similiar experimentation. I was hoping for someone with actual experience with digital amps to chime in.

 

[braddo]

Quote:

Originally Posted by tfarney /img/forum/go_quote.gif Well, this is not good news. I've been listening to the Panasonic receiver with it's digital/op amp/however that works, headphone section for a couple of days. This is its second round in rotation, by the way. I think I'll end up taking it out and putting the old Harman Kardon integrated back in again, for the same reason I did that the last time: I don't hear what I would expect from "improperly driven" Senns. There is no lack of bass control or speed in the transients. There seems to be plenty of detail. It is very clean and fast. But it is also lean. I think I just like the sound of the old Harman Kardon, which is very warm and smooth and somehow manages to be that way without lopping off any detaii... This might blow my plan about building a very neutral system and swapping phones to change presentation. It's not that the HK is better in any objective way. It's just that I enjoy listening to it more. This concerns me a bit. I think that listening to tubes, something I plan on doing very soon, might open a huge can of troublesome worms for me... I'm going to give it a few more days and let my ears adjust a bit, then try the HK again. Then when the tube amp gets here (a Glow I'm trying out), I'll listen to the 3 of them. If my desk can bear the weight. I'll tell you one thing; if this old HK holds up as well in comparison to the modern tube and SS headphone amps I have coming through here on trial, I'm going to be looking for a backup. Tim

i'll help you out.

 

[tfarney]

Quote:

Originally Posted by braddo /img/forum/go_quote.gif i'll help you out.

Thanks, but with what? Helping me find a backup for my old HK or becoming an obsessive tube junkie?

Oh...wait a minute. You have a Yamamoto. I think I have my answer...

Tim

 

[Headdie]

Quote:

Originally Posted by Headdie /img/forum/go_quote.gif I'd also be curious to know if someone has tried to drive headphones with the speaker out of a new T-AMP? This new generation of amplifiers seems to be very hot, but I can't find one with a headphone jack...

If I look for a Yulong TA4780 on eBay, I can read : "Attention, this product is BTL output. The cathode output is not the earth line, so the cathode outputs can’t be connected." I'm not sure if this Yulong is a T-AMP, but I suppose this amp is an example for wich you can't connect standard wired headphones to the speaker out...

But if I look at a PopPulse T-AMP 1, I read that it is a bridged output amplifier. Does it mean that I could connect my DT990 or D2000 to the speaker out?

Sorry, if it's a dumb question...

 

[Navyblue]

Quote:

Originally Posted by Headdie /img/forum/go_quote.gif But if I look at a PopPulse T-AMP 1, I read that it is a bridged output amplifier. Does it mean that I could connect my DT990 or D2000 to the speaker out?

I think it would blow the amplifier up by connecting the ground together on a bridged amplifier, but let someone more qualified to comment.

 

[Headdie]

I just bought some new speakers (Energy Connoisseur RC30) and I'm looking for a stereo integrated amplifier, that will be good for them and hopefully my headphones too (old DT990 and new D2000).

Else than T-AMP, for which I can't find one with a headphone jack, I'm considering Cambridge, NAD and Marantz. I've read that Marantz is serious about the headphone jack. I trust NAD and Cambridge.

Do you have an integrated from one of these brands and be kind enough to tell me what SQ is going out from the headphone jack? I'm also open to any other suggestions...

Thanks guys !

 

[tfarney]

Quote:

Originally Posted by Headdie /img/forum/go_quote.gif I just bought some new speakers (Energy Connoisseur RC30) and I'm looking for a stereo integrated amplifier, that will be good for them and hopefully my headphones too (old DT990 and new D2000). Else than T-AMP, for which I can't find one with a headphone jack, I'm considering Cambridge, NAD and Marantz. I've read that Marantz is serious about the headphone jack. I trust NAD and Cambridge. Do you have an integrated from one of these brands and be kind enough to tell me what SQ is going out from the headphone jack? I'm also open to any other suggestions... Thanks guys !

I suggest you find a support email address for all three manufacturers and ask them if any of their modern amps or receivers have headphone sections that use the main amps stepped down through a resistor, or if they are all op-amp based. If they say op amp, start shopping vintage. If you don't want to crawl around garage sales and consignment shops, then take something to the shop for servicing, you'll find good vintage stuff, up to specs and ready to go on AudioKarma and Audio Asylum, not to mention ebay. A good quality Sansui, Marantz, Yamaha, Harmon Kardon, etc. from the 70s makes a great headphone amp and a great speaker amp. I suspect $300 or less, sometimes a lot less, will get you a really good one, ready to go.

Tim

 

[scompton]

The only T amp I know that has a headphone jack is the Sonic Impact V2 and it's worthless. I think they only put it there because they felt they had to. It's definitely an afterthought and doesn't sound good at all.

That doesn't mean that someone can't make a good headphone jack for a T amp. I may be missremembering, but I think the portable amp from Qables is a T amp. It's also $500 and is just a headphone amp.

I second going with vintage. I have an NAD 3155 integrated amp that has an excellent headphone jack. It's powerful enough to drive a pair of electrets that the previous owner reterminated with a TRS plug. They're not that expensive on eBay. My only problem with it is that the tone controls don't effect the headphone jack.

Your other option is to take your headphones to a store that sells amps and try them.

 

[Headdie]

I read on the net that Marantz PM7001 is good with phones, because it has a dedicated headphone amplifier inside ??? If true, I suppose it would mean that an OPAMP drive the phone jack, instead of the main amplifier... Are OPAMP inferior to the main amplifier in any case?

 

[scompton]

Most dedicated headphone amps are op amp based, so that's not the problem. The problem is that for a lot of speaker amps, the op amp based headphone amp is an after thought. All of the design work goes into the main amp. Once they have that done, they slap together a cheap, op amp based headphone amp just because they need to have a headphone jack. But because 99% of their market is buying the amps for speakers, they short change the headphone section. Some of them sound good and some don't. It's hit or miss and you never really see the headphone sections reviewed so you really need to listen before buying.

I don't know where you live, but you can get good vintage equipment at thrift stores. And you'll have phono input if you ever decide to go with a vinyl setup.

 

[Headdie]

Talking about op-amps, can we also roll them inside integrated or receivers? Do you know brands designed fot it? NAD, Marantz or Cambridge maybe...

 

[scompton]

You might need to contact customer support from the companies to find that out. I know there are DIY forums that talk about modifying amps, but I don't know if they talk about the headphone sections. As I said before, most people buy amps for speakers, not headphones. My wife doesn't like music, she's hard of hearing, so I don't have speakers. I listen 100% to headphones and use my NAD to drive stats and electrets and well as dynamic headphones with the headphone jack.

 

[hugz]

I've been connecting my headphones directly to the speaker jack of my speaker amp for about a year now. sounds great, no worries about blowing anything up

i used a resistor across it for a little while to drop the gain and the decrease in sound quality is certainly no where near what people make it out to be. I'm not entirely certain if there was a change at all, but honestly I never bothered doing any kind of A-B testing with and without resistor.

I dont use a resistor anymore not because of sound quality but simply because there's no reason to use it and it's inconvenient.

Too much "blah blah" back and forth here. its easy enough to connect your headphones to your speaker jack, and easy enough to add a resistor to it

 

[tfarney]

Quote:

Originally Posted by hugz /img/forum/go_quote.gif I've been connecting my headphones directly to the speaker jack of my speaker amp for about a year now. sounds great, no worries about blowing anything up i used a resistor across it for a little while to drop the gain and the decrease in sound quality is certainly no where near what people make it out to be. I'm not entirely certain if there was a change at all, but honestly I never bothered doing any kind of A-B testing with and without resistor. I dont use a resistor anymore not because of sound quality but simply because there's no reason to use it and it's inconvenient. Too much "blah blah" back and forth here. its easy enough to connect your headphones to your speaker jack, and easy enough to add a resistor to it

The degradation in sound quality caused by a resistor is nonsense. Well, I suppose it could be real if the resistor was faulty or really cheap, but consider that the volume control of choice on high-end audiophile headphone amps is the stepped attenuator, which is a whole series of resistors at different values, to step down the full output of the amp.

Consider all the myths and the relationships between them before you begin embracing them.

Tim

 

[Navyblue]

Quote:

Originally Posted by hugz /img/forum/go_quote.gif I've been connecting my headphones directly to the speaker jack of my speaker amp for about a year now. sounds great, no worries about blowing anything up i used a resistor across it for a little while to drop the gain and the decrease in sound quality is certainly no where near what people make it out to be. I'm not entirely certain if there was a change at all, but honestly I never bothered doing any kind of A-B testing with and without resistor. I dont use a resistor anymore not because of sound quality but simply because there's no reason to use it and it's inconvenient. Too much "blah blah" back and forth here. its easy enough to connect your headphones to your speaker jack, and easy enough to add a resistor to it

How do yo do that? Do you simply use a speaker cable, put a female TRS plug on one end and spade/banana plug on the other?

I'm curious because yours just seem too easy.

I built a box with a bunch of resistors inside so that the jack has 5V output and 120 ohms impedance, according to the headphone jack standard. Though it might be quite unnecessary other than it allows me to set my volume knob at a reasonable value.