Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › OTL Tube amps and Grados.
New Posts  All Forums:Forum Nav:

OTL Tube amps and Grados. - Page 2

post #16 of 58
Quote:
Originally Posted by dongringo View Post
How about the WA6 for RS1i and DT880/600? I'm looking for one tube amp that will warm up both. Is this even doable?
I have no idea, as I've never heard either of those combos. I've never heard the RS1i, but all the RS1s I've heard pretty much sound decent through almost anything. I've only heard DT880/600 through Beyer's own amp, which I really didn't enjoy.

The WA6 has a solid reputation, though, and I don't consider it a cheapie amp. I'd be a little concerned with synergy with the Beyers, though, and would prefer to get just one pair of phones and spend the difference on amp or source. Woo 6 SE for Grado, Woo 2 for Beyer, or maybe even a Trafomatic or DNA Sonett? The choices really open up around $1k.

Just some food for thought... no, I haven't heard all the possible combos.

Edit: Actually, doesn't Beyer Manufaktur offer 32Ohm phones? That's the same as the Grados, so they would match impedance wise. Still, impedance alone won't really tell how a phone will react to an amp...
post #17 of 58
Thread Starter 
Quote:
Originally Posted by sampson_smith View Post
Aren't OTL tube amps a bad, bad idea for low impedance cans like Grados? I thought this was (or, at least, should be) common knowledge.
This is what I thought. Hence, me buying a hybrid first time around. But occasionally you see people who seem to have really satisfactory pairings, against all the odds.

Clearly, transformer coupled amps like the WA6 are a much safer bet, given that their transformer allows the output stage to "match" with lower impedance (might be wrong). I would go for an amp like that at the drop of a hat, were it financially feasible.

@ HeatFan12 - I would love to hear your impression of your grados <-> MKIV se
post #18 of 58
Using my ms-pros with my WA2.

I'd have to say, the "improvement" or change in tonality, is definately present, but they perform well unamped, well enough that I'd say that the WA2 isnt necessary at all. It took me a while to adjust to the difference in tonality that the WA2 offered, I wouldnt say its "better" just different. It has seemed to take away some of the harshness and there is perhaps a smiggen more bass. Once I got used to it, I quite liked it.

I noticed with with the solid state amps I've tried though, (few receivers and the cantate/swing) the sound just seemed to be "more." Tonality remained the same, but there was just more sound, not more volume, but more sound. I guess I'd best explain it by saying that everything is fleshed out that little bit more.
post #19 of 58
There are two very valid technical reasons that OTL tube amps are not an ideal match on paper for low impedance headphones:

1. The output impedance of most (but not all) OTL tube amps is high-ish - output impedances of 40-60 ohms are not uncommon. Running a 25 ohm headphone off a 50 ohm output impedance is definitely not ideal.

2. Low impedance, high sensitivity headphones want a lot of current swing, but don't require a lot of voltage. SS devices are generally better at delivering current into lower impedance loads. Tubes are, again very generally speaking, better at voltage swing, and less good at current delivery. Frank Van Alstine, a very talented audio guy who prefers tube-ss hybrid designs for amps, prefers them because he considers the vacuum tube an ideal voltage source, and SS devices an idea current source.

There is also the fact that a high-sensitivity headphone will be less forgiving of even very low level hum, which some cheaper tube amps do have.

So there are good reasons for people stating the mismatch.

That said, I have found the Decware CSP-2, an OTL tube amp, to work well with low-impedance Denons, and I like the RSA Stealth, an OTL tube amp, very much with the medium-impedance JVC DX1000. So the proof is in the listening and the ear of the beholder, and there are no absolutes.

That said, if I was a committed Grado person, I would probably not make a foray into OTL tube amps. For me personally, being a 600 ohm Beyer guy mostly, owning a bunch of OTL tube amps is a pleasure
post #20 of 58
Quote:
Originally Posted by atothex View Post
I've said it before, and I'll say it again: I don't care for cheap tube amps, OTL or otherwise. I listen exclusively to low impedance phones, and cheap OTLs simply don't have low enough output impedance to damp them well. Grado's are easy enough loads, but my ATs just lose all their bass with most OTLs. That's why I don't currently own a tube amp. The reason why the Zana and Microzotl were mentioned here was because their output impedances are extraordinarily low. The Microzotl's is especially crazy, but it's a weird amp, and opinions are mixed.

Anyways, it's up to your own ears, but I would personally choose many things over Little Dot. Namely the CKKIII.
Totally agreed and dead on the dampening factor. Awesome points.


Quote:
Originally Posted by Skylab View Post
There are two very valid technical reasons that OTL tube amps are not an ideal match on paper for low impedance headphones:

1. The output impedance of most (but not all) OTL tube amps is high-ish - output impedances of 40-60 ohms are not uncommon. Running a 25 ohm headphone off a 50 ohm output impedance is definitely not ideal.

2. Low impedance, high sensitivity headphones want a lot of current swing, but don't require a lot of voltage. SS devices are generally better at delivering current into lower impedance loads. Tubes are, again very generally speaking, better at voltage swing, and less good at current delivery. Frank Van Alstine, a very talented audio guy who prefers tube-ss hybrid designs for amps, prefers them because he considers the vacuum tube an ideal voltage source, and SS devices an idea current source.

There is also the fact that a high-sensitivity headphone will be less forgiving of even very low level hum, which some cheaper tube amps do have.

So there are good reasons for people stating the mismatch.

That said, I have found the Decware CSP-2, an OTL tube amp, to work well with low-impedance Denons, and I like the RSA Stealth, an OTL tube amp, very much with the medium-impedance JVC DX1000. So the proof is in the listening and the ear of the beholder, and there are no absolutes.

That said, if I was a committed Grado person, I would probably not make a foray into OTL tube amps. For me personally, being a 600 ohm Beyer guy mostly, owning a bunch of OTL tube amps is a pleasure


Grados, Senns and Denons miss you Rob, since you gave all your love to Beyer...

Dead on again and great explanation.



Quote:
Originally Posted by St3ve View Post
This is what I thought. Hence, me buying a hybrid first time around. But occasionally you see people who seem to have really satisfactory pairings, against all the odds.

Clearly, transformer coupled amps like the WA6 are a much safer bet, given that their transformer allows the output stage to "match" with lower impedance (might be wrong). I would go for an amp like that at the drop of a hat, were it financially feasible.

@ HeatFan12 - I would love to hear your impression of your grados <-> MKIV se

All that being said and since I caught this thread while I was trying out my newly acquired uDac with a tube amp, I did some listening tests.

Here's a pic from yesterday's setup with the uDac (also in the uDac thread)




Westinghouse 5687s and GE JAN-CG-6SN7GT. This amp loves Senns and Beyers and at the time I was using HD650s. Once this thread came up I had my SR225s nearby, so decided to plug them in and give them a listen. Also went up to get one of my Ultrasones. ...I was very surprised at the outcome and thought they would sound "hollow" and not efficient at all. That was not the case, the sound was full, warm, the bass was there and tight too. A very smooth sound that I caught myself listening to the SR225s out of this amp for two hours.

Now on the other side of things as an example. This amp (Xenos 3HA)-




I purchased over three years ago and still own, is unlistenable with Grados. What do I mean by unlistenable? Once plugged in, the volume pot can't even be turned about half a turn, it would be too much in reference to the volume. Not only that, but the sound is very "hollow", "shrilling highs" and just sounds too powerful for them, for lack of a better word. My Senns and Beyers (300 & 250ohm respectively) sound great, the sound is full and deep and the volume knob tracks very smooth.

I thought that was going to be the case (hollow, shrill etc.) with the MPX3, but it was not.


Now onto the MKIVSE St3ve-

Again, really curious after your thread so woke up this morning and set up the MKIVSE where the MPX3 was last night, uDac to Windows 7 laptop all FLAC.

I was going to put in some CBS Hytron 6AK5Ws to add a bit of warmth, but decided against it and kept the GE 5 Star 5654s in there. Nice detailed tube. I figured this was not going to work anyway with my Grados and the sound would probably be hollow etc...

I know David had sent me a new manual in reference to the gain with low impedance phones. Set the gain to "10", used to be "5", grabbed my SR225s and put on some DT (Train Of Thought) and began to listen. Again, not expecting much......Full bodied, warm, smooth, detailed and not fatiguing at all. Myung's bass lines on In The Name Of God were so present and sounded crisp, where sometimes they get clouded in the backround. Don't really need to say anything about the other John, of course the guitars were everywhere and sounded amazing...

Up next my RS1i with "Live At Budokan"...Good times...

At the end of the day, we have to let our ears be the judge if the match is good or not.
post #21 of 58
Thread Starter 
Quote:
Originally Posted by HeatFan12 View Post
Now onto the MKIVSE St3ve-

Again, really curious after your thread so woke up this morning and set up the MKIVSE where the MPX3 was last night, uDac to Windows 7 laptop all FLAC.

I was going to put in some CBS Hytron 6AK5Ws to add a bit of warmth, but decided against it and kept the GE 5 Star 5654s in there. Nice detailed tube. I figured this was not going to work anyway with my Grados and the sound would probably be hollow etc...

I know David had sent me a new manual in reference to the gain with low impedance phones. Set the gain to "10", used to be "5", grabbed my SR225s and put on some DT (Train Of Thought) and began to listen. Again, not expecting much......Full bodied, warm, smooth, detailed and not fatiguing at all. Myung's bass lines on In The Name Of God were so present and sounded crisp, where sometimes they get clouded in the backround. Don't really need to say anything about the other John, of course the guitars were everywhere and sounded amazing...

Up next my RS1i with "Live At Budokan"...Good times...

At the end of the day, we have to let our ears be the judge if the match is good or not.
Sounds great, thanks for sharing your experiences HeatFan12. It is this kind of testimony that tempts me. Essentially, I would like to get a companion to go with my RS1 at some point and am thinking Senn 600-650 (wouldn't mind a totally different presentation). Therefore, i have been eyeballing the MKIV SE as a one-amp-to-drive-them-all. From the fairly active tube-rolling I have been doing with my I+, I have discovered that I have preference for a warm, "tubey" sound.

P.S Train of thought is an outstanding album, and by DT's standards its as heavy as a ton of bricks. Which is great .
post #22 of 58
Quote:
Originally Posted by Skylab View Post
That said, if I was a committed Grado person, I would probably not make a foray into OTL tube amps. For me personally, being a 600 ohm Beyer guy mostly, owning a bunch of OTL tube amps is a pleasure
So, would you say a hybrid like EF5 or Trends PA-10 should be good for RS1i AND DT880/600? I would be using a D4 dac. Also, would a hybrid be considerably 'warmer' than the D4 amp?
post #23 of 58
In my experience, transformer coupled tube amps also do a very good job with Grados.
post #24 of 58
Thanks peanuthead. That's good to hear because I'm also looking into the Woo WA6, but didn't really want to spend that much. Do you know of any other good transformer coupled tube amps more in the $500 or less range?
post #25 of 58
Thread Starter 
Quote:
Originally Posted by dongringo View Post
Thanks peanuthead. That's good to hear because I'm also looking into the Woo WA6, but didn't really want to spend that much. Do you know of any other good transformer coupled tube amps more in the $500 or less range?
These amps, by all accounts, are the dog's borrocks. The transformer-coupled jobs seem to be very versatile. I am umming and ahhring over whether to invest that kind of money too.
post #26 of 58
This is the hardest decision yet, but the WA6 seems to just make sense for my three cans (D5000, RS1i, DT880/600). Hmmm...if it wasn't for the wallet thing...
post #27 of 58
Quote:
Originally Posted by dongringo View Post
This is the hardest decision yet, but the WA6 seems to just make sense for my three cans (D5000, RS1i, DT880/600). Hmmm...if it wasn't for the wallet thing...
In that price range, you can't go wrong with the WA6. Another amp you may want to look at is Mapletree Ear+ HD. Folks seem to really love it with Grados.
post #28 of 58
Mmmm...another option...interesting. Thanks again peanuthead.
post #29 of 58
Quote:
Originally Posted by dongringo View Post
Mmmm...another option...interesting. Thanks again peanuthead.
How about a Doge 6210-II

DOGE 6210-II
post #30 of 58
IME with my PHENIX G3 and SR-325is is that while they sound warm and lush, the sound somewhat odd. The K702 for example is much fuller and inviting, but lacks details, dynamics and definition.

On the other hand my DT880/600 sounds fantastic with the G3 amp. It seems to give them what they need and they are dynamic and full of impact, plus the tubes really smooth them out a lot. The treble is even more forward than on my X-CanV8P.

The HD600 also sounds very good on the G3. It's clearly better than what my X-CanV8P can do for them.

OP if you want the tube sound but want something compatible with Grado's get a hybrid amp like my X-Can. A few are Little-Dot 1+, Bravo/Indeed.
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Headphone Amps (full-size)
Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › OTL Tube amps and Grados.