Head-Fi.org › Forums › Equipment Forums › Portable Headphone Amps › The Sub-$200 Portable Amps Shootout – 13 (+11) amps compared
New Posts  All Forums:Forum Nav:

The Sub-$200 Portable Amps Shootout – 13 (+11) amps compared - Page 9

post #121 of 454
Quote:
Originally Posted by ClieOS View Post

BL-2's review has actually been posted a week ago, you can find it here:
http://www.head-fi.org/t/627659/impression-tube-amp-bl-2-portable-miniature-tube-amp-from-china
Never listen to those eBay desktop tube amp before. I haven't had much use of desktop amp (plus I already have a hybrid amp from FireStone Audio) so I never think of picking one up.

Thanks for writing and linking your review! I suppose the search for a sub $200 amp for the curious-resistance 62 Ohm AKG Q701 continues on...
post #122 of 454
Quote:
Originally Posted by mld218 View Post

I was looking at the Leckerton Audo site and noticed that the UHA-4 can be ordered with a couple different output OP amps.  The one in the review was done with OPA209 what is the difference between that and the standard AD8610ARZ that seems to come standard.

 

Thanks for any input you can give

 

Mike

 

 

The OPA209 is the more neutral/detailed one where the AD8610 is more colored/fun. I have the OPA209 and it sounds fantastic. Crisp, clean, and transparent. I believe Leckerton actually recommends the OPA209. That's the output amp that comes standard on the UHA-6s MKII.


Edited by Origin89 - 9/26/12 at 10:25am
post #123 of 454
Thread Starter 
Quote:
Originally Posted by Origin89 View Post


The OPA209 is the more neutral/detailed one where the AD8610 is more colored/fun. I have the OPA209 and it sounds fantastic. Crisp, clean, and transparent. I believe Leckerton actually recommends the OPA209. That's the output amp that comes standard on the UHA-6s MKII.

Purely on the topic of opamp, I think I still prefer AD8610 overall, but OPA209 is really good sound as well.
post #124 of 454
Quote:
Originally Posted by ClieOS View Post


Purely on the topic of opamp, I think I still prefer AD8610 overall, but OPA209 is really good sound as well.

 

Did you find the AD8610 to be more colored comparably?

post #125 of 454
Thread Starter 
No, AD8610 sounds more transparent to me.
post #126 of 454

Ahh, I thought it was the other way around. I know my OPA209 is really transparent, but I haven't tried the other one.

post #127 of 454

I finally got my C421 AD8620 in today.

 

And wow, I think your descriptions are spot on, ClieOS. Personally, I think they actually sound superior to the O2 when coupled with my ES10.

 

High gain is less hissy than O2, AD8620 gives a very detailed & layered presentation, plus the enclosure is small and portable. I can't say I'll miss my old O2 at all now.

 

Thanks for the review! I read many reviews on the C421 before deciding to pull the trigger after reading your thoughts on them.

post #128 of 454
Thread Starter 
Quote:
Originally Posted by Origin89 View Post

Ahh, I thought it was the other way around. I know my OPA209 is really transparent, but I haven't tried the other one.

There are things I like about both. In the same setup, AD8610 handles layer and resolution generally better than OPA209, but come a little short on width when compared to OPA209. OPA209 is more even in performance, but lacks any particular spot that push it over the top for me.

Quote:
Originally Posted by Bill-P View Post

I finally got my C421 AD8620 in today.

And wow, I think your descriptions are spot on, ClieOS. Personally, I think they actually sound superior to the O2 when coupled with my ES10.

High gain is less hissy than O2, AD8620 gives a very detailed & layered presentation, plus the enclosure is small and portable. I can't say I'll miss my old O2 at all now.

Thanks for the review! I read many reviews on the C421 before deciding to pull the trigger after reading your thoughts on them.

Yep, I find C421-AD8620 with ER4S an great combo myself.
post #129 of 454
Hey ClieOS, when can we expect to see your thoughts on the improved C421 amps?
post #130 of 454
Thread Starter 
Quote:
Originally Posted by aznxpress82 View Post

Hey ClieOS, when can we expect to see your thoughts on the improved C421 amps?

I am not getting a new unit or sending mine back, just the new ferrites (I am on the other side of the world from JDS). They are coming in with the new C421 faceplate I ordered, and shipping is usually a week, if not more. I still have to remove the old parts and solder the new parts in, then remeasure the amp. With everything done, I'll say probably about 2 weeks if nothing goes wrong.
post #131 of 454

c421 Black Edition Headphone Amplifier 8620

 

Sounds lovely! I read over your review of the Sub 100's and it lead me to get an E11 to the cMoy that I already had [I had the cMoy 2.03 2x9V rechargeable] so I liked how you rated the two Amps, so I'm hoping the above amp will be as enjoyable as my cMoy but of course without the coloring!

 

I'm thinking of Pairing this with my 250 Ohm Dt 880s and soon to be 250 Ohm Dt 990 Pros, you think it will be a good combo? [Currently using the cMoy with the dt 880 and it drives it well, just want a little more bass but more imporantly more transparancy]

 

Either way I'm hoping that amp can sever my current and future needs <3

post #132 of 454
Hey ClieOS, how do you measure output impedance? If I need special equipment, do you think an audio gear or guitar specialist shop would be able to measure an amp for me? Also, with the usual recommendation for output impedance to be 1/8th the ohms of the headphone impedance, what is the effect/benefit of impedance adapters such as the one to make an Etymotic ER4S "into" an ER4P (or do I have the two mixed up?)?

Thanks for sharing your expertise!
post #133 of 454
Thread Starter 
Quote:
Originally Posted by Evshrug View Post

Hey ClieOS, how do you measure output impedance? If I need special equipment, do you think an audio gear or guitar specialist shop would be able to measure an amp for me? Also, with the usual recommendation for output impedance to be 1/8th the ohms of the headphone impedance, what is the effect/benefit of impedance adapters such as the one to make an Etymotic ER4S "into" an ER4P (or do I have the two mixed up?)?
Thanks for sharing your expertise!

To do basic output impedance measurement, you will need
(1) A digital multimeter that can measure AC in mV.
(2) A fixed load that you can plug into the amp. I soldered a pair of matched 47ohm resistor to a Neutrik jack for this.
(3) An interconnecting cable. This is for you to measure the unload volatge easily straight from the plug
(4) A tone generator. Any decent USB DAC or sound card with Audacity on the PC will do.
(5) Some math calculation.

You can find the detail here, and it is basically the same thing NwAvGuy has described in his article about output impedance. He uses 100Hz mostly but I choose 1000Hz since it is more widely used. Note that many amp have higher output impedance on the top treble (15kHz~20kHz) so you don't want to measure in those area. Given what need to have, I don't think most typical shops will have the needed fixed load around for output impedance measurement unless they are also doing repair work and has some spare resistors around to play with.

Anyway, 1/8th is the minimum rule most are following. Some even go for the tougher 1/10th rule. The impedance adapter on ER4S (100ohm, 4P is 27ohm) is mainly to reshaped the FR curve to match the Etymotic 'ideal' curve and has less to do with dampening or the 1/8th rule. But in a way, you can say 4P is the colored sounding version of the 4S - it is just a matter of how you interpret words.
post #134 of 454

Can't wait to read your impressions on C421 with low output Z, ClieOS.

 

I got mine changed by JDS Labs directly, and the impact on sound quality is immediately felt. My C421 sounds a lot like a more spacious O2 now.

post #135 of 454
Quote:
Originally Posted by Bill-P View Post

Can't wait to read your impressions on C421 with low output Z, ClieOS.

+1.

I want this amp to pair with my new Classic. I have an iBasso D-Zero with it now, but I'm looking for a little more...

New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Portable Headphone Amps
Head-Fi.org › Forums › Equipment Forums › Portable Headphone Amps › The Sub-$200 Portable Amps Shootout – 13 (+11) amps compared