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TOPIC: Using HA-DSP as pre-amp... bad idea or good idea?

Using HA-DSP as pre-amp... bad idea or good idea? 1 year 9 months ago #34524

  • atolol
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Hi!
I want a unit that would give me reasonably good equalization capability separate of all the Linux/windows annoying shenanigans, with an optical in.
HA-DSP fits the bill absolutely perfectly.
However, HA-DSP is reported to have a relatively high output impedance (around 9 ohms) which is somewhat sub-optimal, particularly for fancy multi-driver in-ear monitors.

Would using HA-DSP as pre-amp for something more "typical" (like say a shiit unit) work? Would that be a good idea? Are there any pitfalls I should keep in mind in terms of picking an amp that would work well with HA-DSP as preamp?
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Using HA-DSP as pre-amp... bad idea or good idea? 1 year 9 months ago #34584

  • devteam
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@ atolol

Optical in, analog out? Is that for a headphone amplifier or actually for an amplifier?
If it's as a preamp, best to use the 2x4HD I think. A better fit than grabbing a headphone amplifier for preamp..

Please give us a bit more info so we can help?

DevTeam
MiniDSP, building a DIY DSP community one board at a time.
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Using HA-DSP as pre-amp... bad idea or good idea? 1 year 9 months ago #34600

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Optical in, analog out.
For headphones

(specifically, multi-driver BA in-ear monitors, which is why I kind of suspect 9 ohms of output impedance to become a bit of a problem)

Basically, I'm planning to upgrade my headphone setup to fancy custom in-ears and decided that upgrading amp part would be wise.

I am also quite tired of little hiccups and glitches that Linux's pulseaudio plugin brings about, which is why I started googling for DACs/headphone AMPs with EQ and DSP functionality, and found the HA-DSP
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Using HA-DSP as pre-amp... bad idea or good idea? 1 year 2 months ago #37654

  • JeffS7444
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I could be wrong, but I did all headphone measurements using HA-DSP as my amplifier, because I figured that any frequency response shifts caused by the amplifier would be automatically corrected.
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Using HA-DSP as pre-amp... bad idea or good idea? 3 months 3 weeks ago #42419

  • FabianB
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I would like to re-instate this thread, because I have the same thoughts about the amplifier inside the HA-DSP.
It's great box, and I do love the DSP-part of it (FIR filters are amazing!).

However, with my planar magnetic headphones the output of the impedance of the amplifier is to great. Almost same ohm as the headphones themself, and when comparing (without DSP) to my JDS Labs Atom, there is a clear degradation of transient response and general sound quality through the HA-DSP. Unfortunately!

So, is it possible to tap the signal inside the HA-DSP right before the amplifier section? Like a line out, after all the DSP and DAC.
I took some photos of the insides of the HA-DSP, great built quality.
If the devteam are inclined, could you show maybe a connection that carries the signal to the amplifier?

Best regards from Sweden,
Fabian
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Using HA-DSP as pre-amp... bad idea or good idea? 3 months 3 weeks ago #42420

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The photos were too big in size to be published right here in the forum.

Can be seen on imgur instead:
imgur.com/a/tJiNDPp
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Using HA-DSP as pre-amp... bad idea or good idea? 3 months 3 weeks ago #42421

  • john.reekie
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You can see the TPA6120 at lower left, perhaps look up the datasheet? I expect there would be signal available on those resistors on either side, but you would be need to be very careful to get the right one. (And you will void your warranty I expect.)
I am not miniDSP support.

"You must ask the right questions." - Dr. Alfred Lanning's hologram.
-> Have you read the User Manual??
-> Have you drawn and posted a diagram?
-> Have you posted a screenshot?
-> Have you posted your config file?
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