Audio Samples : Samar vs Ioaudio Bv08 and Ami T14 OPR 47 and C12 Builds

Hey all
Here are some audio comparisons of  AMI, SAMAR,and Ioaudio  trannys tested in my own C12 and U47 builds.  I recorded the trannys in a bunch of different configurations which are explained the audio. I don't want to say too much to influence peoples findings although it's safe to say the differences are pretty obvious in that the Samar transformers have much less saturation making them more sound more clear and Hi Fi The Ioaudio and Ami were both more colored but both are cool sounds it just depends on what sound your chasing.
Enjoy!

OPR C12 point to point Clone Ami Vs Big core Samar Transformer files





https://onedrive.live.com/redir?resid=558044756F0B7A3D!950&authkey=!AK7Sa-iQy795Bgo&ithint=folder%2c


Various U47 Style builds Ioaudio vs Big core Samar Transformer

Here is some more info on the configurations.

U47 6_5_1 ratio Dual ef800 v Samar 12_1 single ef800_

These files are the Ioaudio tranny 6.5:1 ratio tranny in a 47 style circuit running two ef800 in parallel vs the Samar 12:1 transformer running a single ef800



U47 6_5_1 ratio ef800 v Samar 12_1 ratio single ef800_

These files are the Ioaudio tranny 6.5:1 ratio tranny in a 47 style circuit single ef800 vs the Samar 12:1 transformer running a single ef800

U47 6_5_1 ratio paratube

These files are the Ioaudio and Samar trannies with 6.5:1 ratios in a 47 style circuit running Dual ef800 in parallel.

hope this clears things up


https://onedrive.live.com/redir?resid=558044756F0B7A3D!939&authkey=!AFQ7eortnU8a3Xc&ithint=folder%2c

Thanks for doing this.

C12 first.
I only listened to the (separate) voice and acoustic samples.

Wow. Yup, the difference is pretty obvious. Samar is much more hifi sounding. It sounds more extended, in any case in the lows (my ears took a serious blow after a hearing accident this year, so I'll refrain from the top treble range) and it sounds cleaner, too. I hear a slight scoop in the mids, but that is to be expected from this type of mic. Esses are fine.
AMI sounds lofi in comparison; more middy (and subjectively trebly maybe) and more grainy. Esses are a bit sibilant. The added midrange could be of use, though.
I do like a little character, but here I prefer the Samar.


Henk

Alone again?

I like the top end grit of the AMI.  The Samar sounds cleaner.

On to the U47.

I'm somewhat confused about the first two pairs that have the same  text.
Is that a blind test?

Not sure what you mean Mic Addict?
The labels are different on all files.  The name lengths are pretty long so you may have to check that you're reading the whole thing as each file has either Samar or Ioaudio at the end. 

I find the samar a bit warmer on the acoustic guitar tracks, can't tell a difference on the drum room maybe the samar thickens the snare a tad, and the Ami is more sibilant on the vocal tracks.  I had to use sony headphone cause I couldn't tell on my jackie hr824's  Very close mics from what I can hear, would love to have both, hahahahah.

I listened to the C12s again, this time through a wider range sytem.
The AMI T14 has a noticeable midrange push that, on some sources, could help or complement the edge terminated capsule.
Other than that, to my surprise, I must say I don't like it so much. Especially on acoustic guitar it sounds too dirty to me. I love acoustic guitars and I've owned more high quality ones than is good for me. The sound is not easy to capture truthfully. That's why many prefer SDC mics and no tubes or trannies in the chain. I wouldn't go quite that far, but you do need speed and clarity. The tube C12 with the Samar tranny does a great job. The solo acoustic guitar sounds like an acoustic guitar to me.

I'll add that this is not to put down AMI. It's just a couple of samples from one microphone. I've heard stunning results from the AMI T67 and T49, which aren't even their high end trannies.

Then finally, the U47 clones.
I think I've figured out what's up there.

Samples five and six have a U47 with the paratube; #5 with the ioaudio tranny, #6 with the Samar. I haven't a clue what paratube is (edit: I do now LOL), but I didn't really like either of those.

Numbers three and four have a U47 with the EF800 tube. Those sound the most hifi of the lot, to me. In fact, they remind me more of an M49. Of the two, I slightly prefer the one with the ioaudio transformer. But both are big trannies that sound big, too. No doubt there are pros and cons to both designs (multichambered ioaudio vs. the big core Samar), but I'm not nearly qualified to go into the technical details. Maybe the Samar sounds a little more phase correct? Nah, I'd better stop there.  But it's also a little more more nasal on the spoken voice (actually more noticeable in sample two BTW; see below).  Where the Samar in the CK12 combined superbly (!) with the edge terminated capsule, here it is mated with a center terminated K47 or M7 (?). The ioaudio seems a slightly better match in that regard. To my ears it sounds more even, with nice mid mids and some subtle vintage character. Neumannesque.

Number one has a double EF800 tube configuration (in parallel) with ioaudio's tranny.
It sounds a little less hifi to me than the ones with the single EF800 (regardless of the tranny in those), but to me this one sounds the most like an actual U47.

Thanks for your Impressions Mic addict
To be clear I'll outline what each configuration  is a sorry my naming scheme is a bit confusing

U47 6_5_1 ratio Dual ef800 v Samar 12_1 single ef800_

These files are the Ioaudio tranny 6.5:1 ratio tranny in a 47 style circuit running two ef800 in parallel vs the Samar 12:1 transformer running a single ef800



U47 6_5_1 ratio ef800 v Samar 12_1 ratio single ef800_

These files are the Ioaudio tranny 6.5:1 ratio tranny in a 47 style circuit single ef800 vs the Samar 12:1 transformer running a single ef800

U47 6_5_1 ratio paratube

These files are the Ioaudio and Samar trannies with 6.5:1 ratios in a 47 style circuit running Dual ef800 in parallel.
hope this clears things up

U47 6_5_1 ratio Dual ef800 v Samar 12_1 single ef800_

These files are the Ioaudio tranny 6.5:1 ratio tranny in a 47 style circuit running two ef800 in parallel vs the Samar 12:1 transformer running a single ef800

Click to expand...

Yeah, that's what I thought in the first place (going by what is said) and I wrote my review accordingly. But then I got confused again, probably because the first two written texts both had the word "dual" in them.  So I edited my post. But that text is only the beginning part, of course.
So this means that 2 and 4 are the same microphone, but different takes, no?

Oh, and "paratube" stands for the two EF800s in parallel, of course. Man, I must have been in serious need of coffee!
So 1 and 5 are the same mic, too, no?
That does make me wonder why I didn't much like samples five and six. Something seems different there. Greater distance maybe?

Oh well, at least I tried.  ;D

Ha Ha Sorry to trip you up ;D

All files with the same titles were recorded simultaneously ie two mics were used.

All files with the same titles were recorded simultaneously ie two mics were used.

Click to expand...

Yeah, 3 A/Bs.

I got that, even without coffee. 

Anyway, like I said, the U47(s) with the single EF800, regardless of tranny and despite the headbasket, sounds more like an M49 than a U47 to me. Which is nothing to be "ashamed" of, since the M49 is arguably the better microhone! It just lacks that midrange crunch, for lack of better words.
Am I alone in this?

The issue with the single Ef800 driving the 6.5:1 tramsformer  at typical U47 operating point is that the output Impedance is too high (around 1k!!) which makes the highs and lows suffer and makes the mic sound smaller... For a single ef800 to work better in this circuit the tranny ratio needs a higher ratio around 12:1 or you can use two tubes paralleled to lower the impedance as Saturn sound and Ioaudio and myself have done. it seems the VF14 has an very low plate impedance which very few tubes exhibit and has made substitution difficult.

micaddict said:

Anyway, like I said, the U47(s) with the single EF800, regardless of tranny and despite the headbasket, sounds more like an M49 than a U47 to me. Which is nothing to be "ashamed" of, since the M49 is arguably the better microhone! It just lacks that midrange crunch, for lack of better words.
Am I alone in this?

Click to expand...

I haven't listened to the clips yet, but perhaps this is why my EF802 U47 sounds so unexpectedly similar to my C12. I.e. more hi-fi than a VF14 U47.

Regardless, it doesn't really jive with the "impedance mismatch" thing if the mic actually sounds more hi-fi.

OPR said:

The issue with the single Ef800 driving the 6.5:1 tramsformer  at typical U47 operating point is that the output Impedance is too high (around 1k!!) which makes the highs and lows suffer and makes the mic sound smaller... For a single ef800 to work better in this circuit the tranny ratio needs a higher ratio around 12:1 or you can use two tubes paralleled to lower the impedance as Saturn sound and Ioaudio and myself have done. it seems the VF14 has an very low plate impedance which very few tubes exhibit and has made substitution difficult.

Click to expand...

Yup, I remember Marik saying something of the sort in his White Market thread. I must say both single EF800 mics sound pretty hifi to me, the one with the Samar a little more so than the one with the ioaudio (but both not as hifi as the C12 with the Samar).



Melodeath00 wrote:

I haven't listened to the clips yet, but perhaps this is why my EF802 U47 sounds so unexpectedly similar to my C12. I.e. more hi-fi than a VF14 U47.

Click to expand...

Could be. Please let us know what you hear.
And what tranny did you use in yours?

Regardless, it doesn't really jive with the "impedance mismatch" thing if the mic actually sounds more hi-fi.

Click to expand...

Both the human voice and a (strummed) guitar are midrange heavy instruments. Perhaps the difference would be more obvious with a bass instrument and e.g. some cymbals.



I should probably ask Max and maybe it's a silly question to begin with, but do the four seperated chambers per bobbin in the ioaudio (and original) BV8 have any influence on phase coherence?
And what about tubes in parallel?



Henk

Transformer of Max  done perfectly, phase distortion, and the like may not occur. Often phase inaccuracies occur at the fault lamps, poorly chosen operating point etc.

Thanks. 

The Samar transformer also has Bv08 chambered winding topology so I think the sound difference would be mainly down to core materials.

Re:dual vs single ef800
One of the biggest differences is the proximity effect  is more pronounced

Yeah, that makes sense. Alloys play a huge part. But there's more of course. Making (good) audio trannies seems like an art.