amplifier for compression driver

[MAAC0]

Behringer uses the LM3886 on their claimed 1000W B112D speakers for HF.

 

[kipman725]

In home situations some people use headphone amplifiers as they can drive a few watts and have very low noise and distortion:
Review and Measurements of Neurochrome HP-1 High-Performance Amp | Audio Science Review (ASR) Forum
This amp can do 3W into 32ohm so should also be able to do at least 3W into 16 ohm.

 

[ErnieM]

Any of those Neurochromes will get the job done. Hypex Ncore should work well too.

 

[LineSource]

+1 .... an over designed headphone amplifier in the "Headphone Systems" forum. There are kits based upon using a few ChipAmps in a "precision amp" topology with crazy-good specs into 16ohms. (131 dB of S/N and 0.0009% THD). There is also a klone of the KRELL headphone amplifier with PCB.

eBay offers several production headphone amps based upon this diy work. (JDS-Labs-O2-OBJECTIVE2)

JDS Labs O2 OBJECTIVE2 Headphone Amplifier (Black) 4571461195520 | eBay

=================
The Objective2 (O2) Headphone Amp DIY Project

"The Wire" Ultra-High Performance Headphone Amplifier - PCB's

Marsh headphone amp from Linear Audio

JLH Headphone Amp

 

[spalmgre]

S/N does not explain how much hiss/noise you hear when there is no signal. TI call it "noise floor".

This problem can be compared to OLED TV vs. Led TV where the difference is in showing black or gray between colors.
When you listen on very low volume you hear the hiss/noise between the instruments.

LM3886 has a reported noise floor of 2.0uV. This is the only reported noise floor value I have found. Amps built with this chip can be bought and here is one with SMPS on board.
I have not tested one but it looks promising.

LM3886SMPS | Connex Electronic

 

[Brett]

I would make low noise my first, second and third priority.

I agree. The rest of it is just handwaving.

Some says using the same amps is safe for multi-amp configuration. I don't know if it's true, though.

Yes, providing they provide enough power for the MR etc will produce the same SPL as for the CD.

 

[drdb1]

Are there any low-noise amplifiers comercially available?

In specific I mean transistor-amps with 5-10watts or so...

 

[Pano]

A little strange, but I use my TPA6120 headphone chip amp on 16 ohm compression drivers. It has plenty of voltage swing, enough current and it's sooooo quiet. Works great for headphones, too. 😉

You can pick them up cheap already on a PCB with supporting parts on eBay. Just add power supply.

 

[mitchba]

I highly recommend Amp Camp Amp – diyAudio Store

The ACA's I have are first gen, but with recommended upgrades, including the Meanwell 24V 5 amp low noise SMPS.

Using them on JBL 2453h-SL large format 4" compression drivers: 113 dB SPL, 2.83V (1W) @ 1m (3.3 ft). With it's low voltage gain, no padding is required, just a protection cap for turn off thumps. I have to put my ear right in the JBL 2384 waveguide to hear just the slightest hiss.

Tube like sound from a single ended Class A mosfet design.

 

[spalmgre]

I have to put my ear right in the JBL 2384 waveguide to hear just the slightest hiss.

Thanks for your input. Had thought that I write to you and ask as I knew your setup.

Stefan

 

[drdb1]

Thanks a lot for the suggestions!

The Amp Camp Amp looks very very nice. But even though it´s meant for DIY, I think I´m still missing the basic knowledge to assemble one without hurting anyone 😉
Besides that, it seems like the real deal for aprox. 300$ compared to the first watt amps for 3000$.


Are there any headphone-amps that are stable for 8ohm loads?

 

[Rewind]

FAOW, V2: http://www.firstwatt.com/pdf/art_faow_v2.pdf

Camp amp has an easy power supply but I think my F5 is ten times better. The FAOW would be interesting - 25W is very much overkill for horns.

 

[Pano]

Are there any headphone-amps that are stable for 8ohm loads?

...TPA6120 headphone chip amp ....

You can pick them up cheap already on a PCB with supporting parts on eBay. Just add power supply.

I have several pair of 8 ohm headphones and the TPA6120 runs them with gusto. 🙂
Edit: I can't remember what value output resistors is installed on mine. Maybe 50 or 100 ohms. That helps keeps the amp stable.

 

[drdb1]

Thanks for your advice, but this has to be assembled. I was rather looking for a finished product...

 

[burgunder]

Thanks for your advice, but this has to be assembled. I was rather looking for a finished product...

You can find assebled units with the TPA6120

FX AUDIO PH A2 MINI HIFI audio Desktop Portable Headphone Amplifier OPA2604AP TPA6120 AMP -in Headphone Amplifier from Consumer Electronics on Aliexpress.com | Alibaba Group

 

[drdb1]

Thanks 😉

 

[plasnu]

I use Aleph (IcePower in summer) for my JBL double woofers + compression driver. Here is the picture of my 6 channel Aleph J.

Pics / Measurement
https://www.diyaudio.com/forums/pass-labs/241729-aleph-illustrated-build-guide-174.html#post4641691
https://www.diyaudio.com/forums/pass-labs/241729-aleph-illustrated-build-guide-174.html#post4641659

 

[Pano]

With the modules all you have to do is add a power supply. As for assembly - well - maybe have a look at the name of the forum. 😀

 

[drdb1]

@Plasnu:
Very impressive work!!!

@Pano:
You are correct, but I would have prefered a consumer product. Building speakers myself is enough to work on for me...

 

[Pano]

I know the feeling! 😀