[Cortes]

Hi everyone,
I bought a pair of earphones JH-13 PRO, and I have problem with the volume when I use them with the Lavry DA10.

My setup is this: laptop -> Wavetermina U24-> Lavry DA10-> JH-13. The impedance of JH-13 is so low that I must turn down the volume knob of DA10 to the minimum ( 1) and the volume in foobar to -15db which is not optimum, because software control of volume loses bits and dynamic range. With normal setup in foobar the volume that goes to JH-13 is symply too much.

Any idea how to drive the JH-13 with the volume knob of DA10 without losing dynamic range in foobar?. Thanks.

 

[WalkGood]

If you do not have a low gain switch, have you considered trying an impedance adaptor like this?

 

[Cortes]

I'm afraid those adapters will degradate sound, but as of now it's impossible to listen to JH13 comfortably.

I can't believe I'm the only one having problems of too much volume with these earphones.

 

[WalkGood]

I was trying to recommend a cheap solution for you, a more expensive solution would be to use them with an amp that is designed for sensitive iem’s like the Pico Slim, which has up to 110dB of attenuation. I did get a chance to test this new Pico Slim with my ue11’s, which are also sensitive iem’s and I had to turn the potentiometer almost ¼ way to hear them properly. This sure seems better than what I read about the Lavry DA10, which it’s attenuator provides up to 56dB via it’s potentiometer in 1 dB steps. Not saying anything bad about the Lavry DA10, but this is clearly ½ the amount of steps the Pico Slim offers.

 

[shigzeo]

yeah, an outboard amp is probably the only real way to do it without losing SQ. The lavry itself may not even really be able to drive the JH13Pro anyway, whereas a Slim should and an ALO Rx most certainly does.

 

[WalkGood]

Quote:

Originally Posted by shigzeo /img/forum/go_quote.gif yeah, an outboard amp is probably the only real way to do it without losing SQ. The lavry itself may not even really be able to drive the JH13Pro anyway, whereas a Slim should and an ALO Rx most certainly does.

Not to derail the thread but I recently had the opportunity to see and hear three of the portable amps in this category, the Pico Slim, TTVJ and the ALO Rx, except not the shadow. Of these 3, I would rate them in that order; I really liked the Slim and the TTVJ the best, with the Slim winning out on build quality over the others. Although the ALO Rx is a good amp as well, IMHO it just didn’t have the build quality of the others, I'm sure it has more than acceptable number of steps of attenuation to drive the JH13's properly, but I was unable to find the information looking over their specifications.

 

[shigzeo]

Along the same lines, a portable amp which can drive a 0 ohm load will be your best bet to keep the sound quality to a good level. And Walkgood, thanks for the info. I will be looking at the Slim later on, but I am not sure when!

 

[Cortes]

I'm simply stunned. Now Lavry Da10 is not able to drive a 28ohm earphone?. C'mon!, The problem is it drives them too much.
Is not possible that pumping Lavry DA10 with another sound card removes the problem?.

 

[shigzeo]

I am not talking about volume, my friend, I describing that its output is probably wired for headphones which are much less sensitive and require more power. It has been shown many times that not every source can power a balanced armature earphone. It must go down to 0 ohms to properly do so, and even then, you have to deal with gain, hiss, and at times, weak cap outs.

There are a number of reasons why iem specific headphone amps are coming out. One of them is so that iem users can enjoy flat frequency responses whereas they would not be able to with a headphone amp.

 

[WalkGood]

Quote:

Originally Posted by Cortes /img/forum/go_quote.gif I'm simply stunned. Now Lavry Da10 is not able to drive a 28ohm earphone?. C'mon!, The problem is it drives them too much. Is not possible that pumping Lavry DA10 with another sound card removes the problem?.

Don't be stunned, this is not a question about driving them or not, which clearly it can, it’s a question about driving them too loud. This is why I first recommended a low cost solution and then the real solution. If you read the Lavry DA10 specifications page you’ll notice the facts I stated about its steps of attenuation in post #4 are correct, the potentiometer used was never designed to drive* sensitive iem’s, it's made for full size headphones.

Edit:*rather than drive I would prefer to use the word “adjust” to the level needed for sensitive iem’s. The Lavry DA10's potentiometer just does not have the required number of steps for the proper attenuation of the JH13 Pro’s.

If you are still having a hard time understanding, here is a quote from Justin Wilson in the Pico Slim thread describing the Pico Slim's digital potentiometer that might help you understand better:

Quote:

Q: How much attenuation is there and what does this mean? A: The spec. for amount of attenuation is how quiet the volume can be set. A typical volume control found in a portable amp only has about 70dB of maximum attenuation. This is why with sensitive IEMs, you can still hear the music even with the volume knob all the way down. Worse, as you turn the knob, you have to go several degrees until the left/right channels seem to be matched in volume. At this point you may only have 40 to 60dB attenuation, and the sound can already be too loud. The Pico Slim has up to 110dB of attenuation. Q: How closely are the left/right channels matched? A: The left/right channels are matched better than 0.1dB. The threshold for human hearing is said to be 1dB. Small potentiometer volume controls are only specified for +/-3dB matching, and can be much worse at the quiet range of their volume. It's far from 'high-end' to be listening to something with this much left/right imbalance, especially when the imbalances from your source, amp, and headphones can all add up to something you can easily hear. You never have to worry about this with the Pico Slim. Combine the attenuation and channel matching of the Pico Slim, and try it with IEMs. It's very relaxing & reassuring to be able to slowly turn up the volume, listen at quiet levels if you want to, and the left/right channels are always perfectly balanced. Q: How many steps does the volume control have? A: A popular DACT stepped attenuator in home amps only has 23 volume steps. Most digital volume controls offer 16, 32, or 64 volume steps. A potentiometer technically has infinite steps, but there are the problems described above that limit its use. The Pico Slim has 255 volume steps, which will be completely seamless so it will sound and feel like there are no steps at all.

 

[Cortes]

WalkGood and shigzeo,

thanks for your comments, I appreciate it. I think I begin to understand the issue ufff. Not easy fix.

OK, I think I'll create a thread to find a solution for a story with three characters: Lavry Da10, JH13 Pro, and Genelec 8020. I'd like a simple solution, not several dacs/amps on my desktop.

Best.

 

[WalkGood]

Quote:

Originally Posted by Cortes /img/forum/go_quote.gif WalkGood and shigzeo, thanks for your comments, I appreciate it. I think I begin to understand the issue ufff. Not easy fix. OK, I think I'll create a thread to find a solution for a story with three characters: Lavry Da10, JH13 Pro, and Genelec 8020. I'd like a simple solution, not several dacs/amps on my desktop. Best.

Simple is to use an impedance adaptor or inline volume control for headphones … Excuse my ignorance but what do near field monitors have to do with the JH13 Pro and the fact that the Lavry Da10 doesn’t provide enough steps of attenuation for you to listen to your customs at low enough levels. BTW you can read the potentiometer information from their manual on pages 4 & 5 starting at “E. VOLUME CONTROL.”

 

[Cortes]

Quote:

Originally Posted by WalkGood /img/forum/go_quote.gif Simple is to use an impedance adaptor or inline volume control for headphones … Excuse my ignorance but what do near field monitors have to do with the JH13 Pro and the fact that the Lavry Da10 doesn’t provide enough steps of attenuation for you to listen to your customs at low enough levels. BTW you can read the potentiometer information from their manual on pages 4 & 5 starting at “E. VOLUME CONTROL.”

Hi WalkGood,
it's just that I feed my monitors from the XLR output of Lavry and until now I feeded my ER4p from the headphone output of the Lavry. A clean and not too expensive solution.

Best.

 

[WalkGood]

Quote:

Originally Posted by Cortes /img/forum/go_quote.gif Hi WalkGood, it's just that I feed my monitors from the XLR output of Lavry and until now I feeded my ER4p from the headphone output of the Lavry. A clean and not too expensive solution. Best.

I understand, apologies I was being sarcastic. Good point on the ER4p as they’re only 27 Ohms VS the JH13 Pro’s 28 Ohms, unlike the ER4b or the ER4s which are 100 Ohms, which would certainly work best in your situation.

With that known, I would think the ER4p wouldn’t work well either, but if it's working fine, it’s possible that they are not as sensitive than the JH13 Pro’s and that’s why I stated that an impedance adapter or inline volume control should be your lowest cost solution.

 

[shigzeo]

The ER4P are quite insensitive - useable for me with a variety of horrible sources and one of the reason I prefer them to many iems. The JH13Pro too, isn't that sensitive, but it will get very loud, very quick. And, it thrashes the output of amps which are made for headphones rather than iems. I mean it when I say that it is hard to drive.