[scootermafia]

The fact is, it's an IC based amp of some sort, but not a traditional IC of the sort that we've heard of. As opposed to transistors, or tubes. Some sort of 8 pin chip is providing the audio. As we know with small chips in T-amps, a little can go a long way. A CMOY is a specific circuit, not necessarily the one here, depending on how you lay everything out it's going to change the sound. I can only assume that this IC simply sounds way better than other ICs and that Vinnie picked the right parts and layout. Yes, it does superficially look like a CMOY. And products like the RA-1 you can see every part in it and tell that it literally is a CMOY. I generally subscribe to Audio-GD's bigger/more complex is better philosophy, but I still doubt that Skylab and Headphoneaddict just simply don't know what they're talking about. Lots of people on here though, myself included, are still dubious on small circuit boards and we'd have to listen to one to be convinced, and until my pockets are full again...

It seems that all Vinnie does all day is look for efficient, little-known, small parts that sound good and do things in a nonconformist way, versus the Audio-GD way of paralleling mountains of parts into a motherboard-like circuit design. Both ways seem to work as I don't see a lot of either of their products on the FS forum.

 

[Skylab]

Quote:

Originally Posted by scootermafia /img/forum/go_quote.gif It seems that all Vinnie does all day is look for efficient, little-known, small parts that sound good and do things in a nonconformist way, versus the Audio-GD way of paralleling mountains of parts into a motherboard-like circuit design. Both ways seem to work as I don't see a lot of either of their products on the FS forum.

And indeed, both RWA and Audio-GD make products that sound very good, in my experience.

 

[gp_hebert]

Quote:

but I still doubt that Skylab and Headphoneaddict just simply don't know what they're talking about

No offense to these two reviewers, but you shouldn't trust someone just because they write a lot of reviews. I'm not familiar with Skylab reviews, but I've had my fair share of disagreements with HeadphoneAddict's reviewing methodology and I know for sure I personally wouldn't base my purchases on his reviews. Having a similar approach to audio and similar music tastes with a certain reviewer is much more important than the fact that someone apparently has a lot of experience and writes a lot. My 2 cents...

 

[Skylab]

Quote:

Originally Posted by gp_hebert /img/forum/go_quote.gif No offense to these two reviewers, but you shouldn't trust someone just because they write a lot of reviews. I'm not familiar with Skylab reviews, but I've had my fair share of disagreements with HeadphoneAddict's reviewing methodology and I know for sure I personally wouldn't base my purchases on his reviews. Having a similar approach to audio and similar music tastes with a certain reviewer is much more important than the fact that someone apparently has a lot of experience and writes a lot. My 2 cents...

No one should ever make purchase decisions based solely on one review IMO, no matter how experienced the reviewer, and it is a very good idea to find a reviewer that has similar philosophies and sonic proclivities so that you're more likely to have the same experience with a product that the reviewer did. I will point out, however, that unless the reviewer has done a healthy amount of reviewing, there is no way to know if you're likely to agree with him/her or now - this cannot be determined on the basis of one or two reviews.

I also added this to the review since people have asked - my review methodology is as follows: I use an SPL meter and broadband pink noise from the Stereophile Test CD 3 to calibrate listening levels to 80dbA. All listening, with every headphone, and with other amps used for comparison, is done at this level, so that volume differences are eliminated to the degree technically possible. Headphones used in this review were the Beyerdynamic DT770, 880, and 990; the JVC DX1000, and the Kenwood KH-1000. Sources were my Denon CD player, the StyleAudio Carat-Topaz DAC, an iMod iPod, and my Vinyl Rig.

 

[mr.khali]

Quote:

Originally Posted by gp_hebert /img/forum/go_quote.gif No offense to these two reviewers, but you shouldn't trust someone just because they write a lot of reviews. I'm not familiar with Skylab reviews, but I've had my fair share of disagreements with HeadphoneAddict's reviewing methodology and I know for sure I personally wouldn't base my purchases on his reviews. Having a similar approach to audio and similar music tastes with a certain reviewer is much more important than the fact that someone apparently has a lot of experience and writes a lot. My 2 cents...

You are absolutely correct. No one man's opinion is more important than your own but there are few people on this forum that have put in the time and effort to review the amount of gear that Skylab and Headphone Addict have. I like to read their reviews as a good reference point for gear that I am interested in and then try to look for common points made by others that have also tried the item in question. Knowing their preferences you agree and disagree with can be equally as helpful in making a purchase. I am relatively new in this hobby so I look for all the experienced help I can get.

 

[mrarroyo]

Quote:

Originally Posted by gp_hebert /img/forum/go_quote.gif No offense to these two reviewers, but you shouldn't trust someone just because they write a lot of reviews. I'm not familiar with Skylab reviews, but I've had my fair share of disagreements with HeadphoneAddict's reviewing methodology and I know for sure I personally wouldn't base my purchases on his reviews. Having a similar approach to audio and similar music tastes with a certain reviewer is much more important than the fact that someone apparently has a lot of experience and writes a lot. My 2 cents...

I also do not always agree with the results that HeadphoneAddict or Skylab reach in their reviews. Frankly we should not since we have different gear, music, biases, expectation, and EARS. However what perhaps you are missing is that this is one of those rare occasions where all three of us agree the Amphora is a very very nice sounding amp. Believe you me, this does not happen often.

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif No one should ever make purchase decisions based solely on one review IMO, no matter how experienced the reviewer, and it is a very good idea to find a reviewer that has similar philosophies and sonic proclivities so that you're more likely to have the same experience with a product that the reviewer did. I will point out, however, that unless the reviewer has done a healthy amount of reviewing, there is no way to know if you're likely to agree with him/her or now - this cannot be determined on the basis of one or two reviews. I also added this to the review since people have asked - my review methodology is as follows: I use an SPL meter and broadband pink noise from the Stereophile Test CD 3 to calibrate listening levels to 80dbA. All listening, with every headphone, and with other amps used for comparison, is done at this level, so that volume differences are eliminated to the degree technically possible. Headphones used in this review were the Beyerdynamic DT770, 880, and 990; the JVC DX1000, and the Kenwood KH-1000. Sources were my Denon CD player, the StyleAudio Carat-Topaz DAC, an iMod iPod, and my Vinyl Rig.

I totally agree, each potential buyer should spend some time with the gear they plan on purchasing. This is IMO more important once the gear exceeds an amount (to be set by each of us). However, I also understand how hard it may be for those who live out of the way or in other countries. It is in this occasions where we have to go on what we read and the reputation of the seller, in this case both ALO and Vinnie have through their hard work achieved very good reputations.

Like Skylab I also match the volumes, I use a dB meter I purchased from Radio Shack (Part No. 33-2055). The process is repeated for each can since each has a different impedance. BTW I set mine at a much lower level (66-70 dB) depending on the mood and headphone, yes I listen at low levels.

 

[Zimm]

Wow, a lot of unneeded drama that has happened here. I trust Skylab's review along with mrarroyo and headphoneaddicts' impressions enough to know that the Amphora is not a dressed up CMOY. The only regret I have about buying one is how long I have to wait until I get to listen to it myself. Thanks for the review Skylab!

 

[vkvedam]

Quote:

Originally Posted by Zimm /img/forum/go_quote.gif Wow, a lot of unneeded drama that has happened here. I trust Skylab's review along with mrarroyo and headphoneaddicts' impressions enough to know that the Amphora is not a dressed up CMOY. The only regret I have about buying one is how long I have to wait until I get to listen to it myself. Thanks for the review Skylab!

Don't worry Zimm, you'll get your chance.

 

[HeadphoneAddict]

I think with any amp that it takes time to get to know the nature of the amp and its capabilities, and I spent more time with Zimm's than Naamanf did (10 minutes) to know what it could do. It equals some of the best SS amps I have heard in some areas and bests them in others, beats some tubes amps I have tried and comes in below others. It's not God's gift to Headphone world, but it is a great man's gift.

It doesn't jump out and grab you by the throat and say, "Wow, I'm good aren't I now!" (said in the voice of the shark mocking the dolphins in A Sharks Tale), but rather you realize that you are enjoying the music more and forgetting to analyze and pick apart the sound or the performance. The P-51 is one of those amps that is more likely to jump out and strike you as more exciting, and at first listen it appears to be on the level of the Amphora, but that can get fatiguing over time without the right source and headphones. And, prior to the Amphora the P-51 was my best portable amp. The Amphora just seems to make a great buffer between most of my sources and headphones, to bring the true music out.

There are definitely better headphone amps out there than the Amphora (such as my Maxed WA6) but you have to pay your money to get them too. Yes, it would be nice if a cheaper version without the Vcaps was available to those who don't have iMods, but as I understand it the Vcaps are ALSO to prevent DC offset from going backwards into the source, not just to keep the DC offset of the iMod from entering the amp. Some can argue that then is a design flaw, but I don't see it that way.

 

[naamanf]

Quote:

Originally Posted by HeadphoneAddict /img/forum/go_quote.gif ... but as I understand it the Vcaps are ALSO to prevent DC offset from going backwards into the source, not just to keep the DC offset of the iMod from entering the amp. Some can argue that then is a design flaw, but I don't see it that way.

It all makes sense now. The input caps are needed to block the dc offset used in the feedback loop. Varying the feedback also changes the closed loop gain. I am going to have to say our mystery chip is either this or one from the same family.
http://www.national.com/ds/LM/LM4880.pdf

 

[spritzer]

That would fit the bill. Feed the 9VDC through a fixed voltage regulator (7805 for instance) and you've got an instant amp. These chips are used in cheap CD players and boomboxes to drive the headphone outputs so it is actually worse then a CMOY.

 

[Skylab]

Hopefully, however, we can avoid jumping to conclusions about whether or not that is ACTUALLY what is being used, since all that has been offered so far is speculation.

 

[naamanf]

Quote:

Originally Posted by Skylab /img/forum/go_quote.gif Hopefully, however, we can avoid jumping to conclusions about whether or not that is ACTUALLY what is being used, since all that has been offered so far is speculation.

I don't think that is the exact same chip but I am fairly certain that it is pin compatible to the one used. That narrows it down to a couple of possibilities.

 

[KHarvey16]

I hate to bump a somewhat old thread, but I was browsing and had a question. Looking into the Amphora, I see the product page saying that it consists of the headphone module from the Isabella, by Red Wine Audio. I followed the link and found a review of the Isabella done by 6moons. As I expected (and apparently the 6moons reviewer did as well), the headphone module in the Isabella tube amp is basically a buffer. The gain is provided by the tubes. The IC, if the design has not been changed, is a zero gain buffer.

So...what's up?

 

[krmathis]

How I understand Vinnies post here is that in the Isabella the Isabella headphone board don't provide gain, but just acts as a buffer. While the board provide gain in the Amphora and the upcoming "Isabellina HPA". Hence it acts differently depending on which unit its mounted in.
http://www.head-fi.org/forums/5693432-post24.html

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