[SoupRKnowva]

Quote:

Originally Posted by jcx /img/forum/go_quote.gif it is not near "best", but unity buffer isn't as bad as an amp with with gain and a high Z attenuator purpose designed transformers really are the quality way to go - get a step-down with ratio sized to give proper "system gain structure" and you actually get improved S/N releative to any active device solution and with these super sensitive, low Z IEM you really need to fight for S/N given the level mismatch even with low V portable players - much less desktop source with conusmer 2 Vrms or even worse pro balanced drive levels - they will HISS your source (without added amp or buffer) is putting out hundreds of times the power neded to get to 120 dB SPL with these IEM so you can end up using > 40 dB attenuation in your signal chain for all of your listening - the same as "throwing away" >6 bits of resolution in the DAC 10:1 transformer divider ratio still lets you drive JH13 to >120 dB from consumer level DAC outputs and would reflect 2.8 KOhm load to the DAC output - which any "audio quality" op amp should drive without issue - much less audiophile designer discrete DAC I/V or buffer circuits once you have transformer coupling you autiomatically have balanced impedance drive - and you can reterminate (Ray's new 4-pin connector?) without requiring a balanced DAC output

so you're saying i should put a step down transformer on the input of my buffer and then use 4 boards for balanced drive? that sounds like a pretty good idea. Cause 2 volts out of the dac into 28 ohms produces 148 mW!! but at 10:1 its only .2 volts, which into 28ohms is 1.4mW, which would produce a little over 119dB in my jh-13's haha so even after the transformer, i will need attenuation, what do you think i should get for that, JT or lightspeed, or something else entirely, like just a RK27 or something?

wait, if i were using the transformer, i would be getting balanced, which means double the voltage i just said, man, these things really dont need much power.

thanks for the info

 

[moonboy403]

I'm planning to get a MiniMax specifically for my JH13 Pro. Anyone care to comment on how it might turn out or if it's a good idea at all?

 

[hockeyb213]

Tubes and high sensitivity iem's in general are not a good mix but I do not have a minimax to comment. I know that headphoneaddict did enjoy his wa6 with his jh-13's though.

 

[moonboy403]

Although I don't know the exact output impedance of the Millet MiniMax, but it is a hybrid amp so impedance shouldn't be too high.

 

[HeadphoneAddict]

Quote:

Originally Posted by hockeyb213 /img/forum/go_quote.gif Tubes and high sensitivity iem's in general are not a good mix but I do not have a minimax to comment. I know that headphoneaddict did enjoy his wa6 with his jh-13's though.

The EF2 and WA6 are great with IEM, with nice low volume channel balance and quiet background and no excessive gain. The EF1 and EF5 were not good with IEM because of the higher gain, music leaking through at zero volume, and low volume channel imbalance. My son's Millett SSH is quiet but the volume pot is not precise enough for IEM.

In between was the Cavalli CTH which worked well with IEM as far as gain/channel balance and noise, but gave them all a base boost with the Mullard long plate 12AU7 that I was using. Qinpu A-3 was good with Senn IE-8, but I don't recall results with any others I tried without pulling up my review. It was quiet with good channel balance at low volumes though.

 

[Cortes]

Quote:

Originally Posted by HeadphoneAddict /img/forum/go_quote.gif The EF2 and WA6 are great with IEM, with nice low volume channel balance and quiet background and no excessive gain. The EF1 and EF5 were not good with IEM because of the higher gain, music leaking through at zero volume, and low volume channel imbalance. My son's Millett SSH is quiet but the volume pot is not precise enough for IEM. In between was the Cavalli CTH which worked well with IEM as far as gain/channel balance and noise, but gave them all a base boost with the Mullard long plate 12AU7 that I was using. Qinpu A-3 was good with Senn IE-8, but I don't recall results with any others I tried without pulling up my review. It was quiet with good channel balance at low volumes though.

EF1, EF2, EF3, getting lost here.... sorry, what's that?.

Could we make a list of the stand-alone amps we have have references work well with JH13?. Assuming, of course, that they must be superior to any portable amp.



- WA6
- DNA Sonnet
- Others?. Solid state ones?

 

[SoupRKnowva]

im pretty sure a GS-1 would sound pretty awesome with one, since it has lower gain than the gilmore lite, also the apache is supposed to sound pretty awesome with it too. Also hockeyB says the B22 sounds damn good with it as well.

 

[Cortes]

Quote:

Originally Posted by SoupRKnowva /img/forum/go_quote.gif im pretty sure a GS-1 would sound pretty awesome with one, since it has lower gain than the gilmore lite, also the apache is supposed to sound pretty awesome with it too. Also hockeyB says the B22 sounds damn good with it as well.

Apache is way too expensive, B22 too. I'll check out GS-1, the standard configuration without stepped attenuator cost less and might be an option.

If anyone has compared WA6 and GS-1 (cheap version) with JH13 would be great.

 

[HeadphoneAddict]

Quote:

Originally Posted by Cortes /img/forum/go_quote.gif EF1, EF2, EF3, getting lost here.... sorry, what's that?. Could we make a list of the stand-alone amps we have have references work well with JH13?. Assuming, of course, that they must be superior to any portable amp. - WA6 - DNA Sonnet - Others?. Solid state ones?

The EF1, EF2 and EF5 are economical tube hybrid amps make and sold by head-direct.com, a popular head-fi sponsor. A-3 is a tube hybrid head-direct sells from another manufacturer, with 8-watt speaker amp and it's designed for headphones over 100 ohm impedance but some IEM work with it.

 

[jcx]

anyone posting "use Amp X" doesn't understand the probelm
- especially when X is noisey to start with, has Voltage gain and high output Z (eg cheap tube amps)

they need to learn about audio system gain structure and noise in amps and typical resistive attenuators

you really, really shouldn't want to listen with >40 dB attenuation in your signal chain to reach "Rock Out" SPL - you will have hiss, and cheaper Volume pots have tracking problems that are larger at higher attenuation


I'm suggesting a (pair of) step down transformer is the only part you need:

DAC-Xfmr-IEM

10:1 from a 2V line out give 0.2 V @ the jh-13

.2 V into 28 Ohm, 119 dB sensitivity IEM = 120 dB SPL

even 100 dB SPL is too loud for continuous listening and very few recordings have >20 dB dynamic peak/ave so reaching 120 dB SPL is usually considered excessive when I argue for dynamic headroom in other threads here - today with loudness war compression everywhere even 12 dB peak/ave is considered a dynamic recording

Xfmers are the only way to attenuate without losing S/N

while moving coil phono input transformers are close to whats needed you'd probably have to ask for a custom design from one of the audio xfmr companies - often the cost premium is low < ~2x similar standard part

Jensen already puts their own quality audio xfmrs in (ugly) boxes with xlr and/or RCA so they should be able to make a complete custom solution quickly


most here appear to buy into audiophile parts fetish and "must have" name parts - but at the highest end of that spectrum transformer volume controls are considered the ultimate endpoint

I don't think the existing "passive pre" TVC boxes will have inital step down or low enough winding R on the output but if you need separate Volume control then a custom xfmr version of a TVC passive pre is the way to go for sensitive IEM

 

[gregeas]

The Pico DAC/amp works great with the JH13s. Gain is still a bit high even at the low setting, but the best of any amp I tried with them.

The Pico was my go-to, but I had to send it back to Justin for a repair a few weeks ago.

 

[YtseJamer]

Quote:

Originally Posted by moonboy403 /img/forum/go_quote.gif I'm planning to get a MiniMax specifically for my JH13 Pro. Anyone care to comment on how it might turn out or if it's a good idea at all?

I have tried the Millet Hybrid MiniMAX (the 2009 version with the 12FK6 tubes) with my JH13s and the sound quality was very good but I wouldn't say that it was better than my Pico or my ALO Rx.

 

[SoupRKnowva]

Quote:

Originally Posted by jcx /img/forum/go_quote.gif anyone posting "use Amp X" doesn't understand the probelm - especially when X is noisey to start with, has Voltage gain and high output Z (eg cheap tube amps) they need to learn about audio system gain structure and noise in amps and typical resistive attenuators you really, really shouldn't want to listen with >40 dB attenuation in your signal chain to reach "Rock Out" SPL - you will have hiss, and cheaper Volume pots have tracking problems that are larger at higher attenuation I'm suggesting a (pair of) step down transformer is the only part you need: DAC-Xfmr-IEM 10:1 from a 2V line out give 0.2 V @ the jh-13 .2 V into 28 Ohm, 119 dB sensitivity IEM = 120 dB SPL even 100 dB SPL is too loud for continuous listening and very few recordings have >20 dB dynamic peak/ave so reaching 120 dB SPL is usually considered excessive when I argue for dynamic headroom in other threads here - today with loudness war compression everywhere even 12 dB peak/ave is considered a dynamic recording Xfmers are the only way to attenuate without losing S/N while moving coil phono input transformers are close to whats needed you'd probably have to ask for a custom design from one of the audio xfmr companies - often the cost premium is low < ~2x similar standard part Jensen already puts their own quality audio xfmrs in (ugly) boxes with xlr and/or RCA so they should be able to make a complete custom solution quickly most here appear to buy into audiophile parts fetish and "must have" name parts - but at the highest end of that spectrum transformer volume controls are considered the ultimate endpoint I don't think the existing "passive pre" TVC boxes will have inital step down or low enough winding R on the output but if you need separate Volume control then a custom xfmr version of a TVC passive pre is the way to go for sensitive IEM

so a 10:1 stepdown transformer, then JISBOS with sigma PSU, but what for volume? JT? or transformer volume control as well?

 

[jcx]

no active devices/power supply required - any existing TVC passive preamp should be able to be directly connected between source (DAC output) and a (custom) 10:1 step down xfmr and thence to the jh-13

the django passive pre kit and other kit/parts for TVC volume control can be found at

AVC TVC Transformers | Diy HiFi Supply


possibly some tube output xfmr with 2 or 3.2 Ohm output taps could be off-the-shelf but probably low frequency compromized step down options

 

[SoupRKnowva]

Quote:

Originally Posted by jcx /img/forum/go_quote.gif no active devices/power supply required - any existing TVC passive preamp should be able to be directly connected between source (DAC output) and a (custom) 10:1 step down xfmr and thence to the jh-13 the django passive pre kit and other kit/parts for TVC volume control can be found at AVC TVC Transformers | Diy HiFi Supply possibly some tube output xfmr with 2 or 3.2 Ohm output taps could be off-the-shelf but probably low frequency compromized step down options

Ok i think im kind of confused, you're saying that we dont even need a current buffer like Fallen Angel was saying earlier in the thread? I didnt think the DAC could power the headphones. Wait, i guess with the step down we're going to have more current available, i think you're on to something. What do we need to the pre for? why just the transformer attenuator? or is the input impedance not high enough?

Edit: whats the difference between AVC and TVC? i thought from your post they were the same, but on that site they are different categories. And you're saying to buy one of those pre's, but put an aditional step down on the input? and buy that from jensen? or Koyaan I Sqatsi recomended Cinemag in another thread where we were talking about audio transformers. Just found Sowter transformers as well, which do you guys think would be best?

And from a over all viewpoint, what kinds of impedances should i have on the input/output of both the step down transformer, and the input/output of the attenuator transformer? should it be high/low and then high/low? cuase the final out needs to be as close to zero as possible for the headphones dampening factor