Well I did mentioned a possibility of "my ears getting used to. I've been comparing it with my two dedicated players and it is not a day a night type of difference. I imagine that there may be some electrolitc output caps in the earphone outputs. Those type components are known change sound...

Here is an update. It appears that my iphone headphone output was not "broken in". It sounds better now after about 4 hours of use. I have my phone for a month but never used earphone output until few days ago. I compared it again with my other music player to make it was not a case of my ears...

Thanks for the suggestion of using a different music player app. My iphone is about a month old.

I have iPhone 6 plus and it is my first phone that I plan on using it as music player device for travel. This is also my first iPhone (and Apple) product. I've been using dedicated players in the past from Rio and sandisk but they were aging so it was time to use my phone as a music player. I...

It appears that SuperMacro V3 will not be using BUF634U buffers until August. Read more here http://www.fixup.net/talk/topic.asp?TOPIC_ID=834

You will want to keep the two ground connections from the two SM V3 separated by modifying your headphone cable and plugs to accept dual 1/8" or 1/4" connectors. I did that on my HD600 using DIY 4-channel amp. The result was just awesome. Bass definition and imaging was like nothing else I...

Yes, I did mention that opamps make the most difference in all well-designed amps and SM V3 or V1 are not exceptions. I used OPA627 opamps on both amp versions. I don't have SM V1 so I cannot compare it to SM V3 now. My assesment was based on my memory comparing amp to source. My former SM V1...

I have SM V3 (sold SM V1, MINT and PIMETA) and two DIY home amps. The SM V1 and V3 measures extremely good in regards to THD, noise and intermodulation distortion. The SM V3 however looses to SM V1 in channel crosstalk performance. It measures as good (or bad) as a MINT amp which tells me that...

Backdrifter, I still "hear" difference between cables. My HD650 cable "sounds" different than the HD600 ones. The real question is the difference due to Placebo or actual electrical difference between these two cables. I'm starting to believe on the former because its effect is inconsistent. I...

The fact that you seem to acknowledge that test condition can affect people ability to hear difference speaks volume by itself. As I said before, I was in the same position as a lot of subjectivists in here. Always thinking that those DBT tests were made to screw 'us'. Name a factor in a DBT...

In most DBT test there is usually a training session. You listen to different sources and verify "audible" difference exists. The test is usually not carried out if you cannot hear difference sighted. The interest portion of DBT tests is that most listeners hear difference when they know what...

I don't know anyone in the objectivist camp that have said that the cheapest cable will sound the same. However, a decent cable with good enough electrical properties does not need to cost that much to perform as good as other much more expensive ones. My estimate of $300 was based mainly on...

Wrong, I did not said I did not "hear" difference between cables. I'm convinced that the difference is due to Placebo effect. Why don't you put you trusty ears to the real test? I really believed in trusting my ears and always chearleading all those brave enough to test their hearing ability...

Quote: Originally Posted by Oski While I believe in the differences in cables can be heard and even pass a perfectly executed DBT, even if it comes down to placebo effects, do doctors not actively prescribe placebos to patients and do placebos not actually cure people? I have...

Quote: Originally Posted by plainsong but there are many things in music that cannot be measure by scientific method. Your ears count! Your ears (or hearing) do count in a blind test, so what is wrong with this scientific method? Do you need your eyes for your ears to work...

I don't have schematic for it, it was in my head when I built it. The circuit is rather simple but with careful component and ground trace layout. It is very similar to a PIMETA's one without multi-loop feedback configuration but with double ground outputs. If you are interested you can send...

It sounds like your problem is either 1) bad solder joint or 2) oscillating opamp. What opamp are you using? What is the current draw of your amp?

My amp has single-ended RCA jack inputs only so the input grounds are tied together. Originally I thought about doing a true differential headphone amp that was switchable for single-ende inputs. This will raise the issue you've brought below. Beside the issue mentioned below (how to tie the two...

Here is my first completed 4-channel headphone amp. Technically is not really a 4-channel amp. It is basically a two channel amp with dual buffered ground channel. There are two 1/8" insulated jacks for L and R output and a 1/4" output for standard 3-channel output. My Sennheiser cable that I...

You should check virtual ground voltage, your rail splitter chip could be damaged. 16V caps are usually connected to virtual ground and only see half of the 19V supply. I've found out that high ripple from the output of unregulated DC supply can easily damage the rail splitter chip. The rail...

I did not comment on difference between SM versions. However I will not be surprised if the actual difference is small since I believe that most well-designed headphone amps sound much closer to each other than most people in this forum believe. As for the supermini-3 sound, I don't much...

Same concept as 3-channel except for separate ground output for left and right channel. That is why I bought I spare Sennheiser cable to split the left and right ground connections. Quote: Originally Posted by goto2003 Wow, four channels, cool! Forgive my ignorance, what the "four"...

I disagree with the speculation about supermini-3 sounding better than SM V1.0. There is a small improvement with 3-channel design assuming everything else is the same. The SM V1.0 is not a 3-channel design but it does have a buffered virtual ground. The main difference between this topology and...

Damn! I sold my SM V1.0 last week. I wouldn't mind keeping a good portable amp for around $100 eventhough I don't need portable amp. Quote: Originally Posted by MountainGoat No need to send the old board back. In Xin's site, he even suggest you to get the case then make another Amp...

Indeed, both of these amps were designed with different approach. I now believe that optimizing a circuit topology using specific opamp is the best approach for high-end headphone amp. Even using socket for opamp and buffer actually degrade signal quality. It took me days if not weeks of...