Recommend amplifier: usb input, min 100W at 8ohms, HPF control

A

adrhc

Junior Audioholic
I don't get where you developed this obsession with "HPF", or why you think you must have it at your fingertips.
Have you measured your system and have some nasty null or peak ?

Its real simple...your amp/AVR sets a crossover point. Anything below is LP, anything above is HP.
Of course the frequency is not a knife edge, there will be overlap both ways.

If you want to adjust the HPF portion, it's real easy with an AVR. Just go into the room correction programs graphic equalizer and adjust it there (frequencies that have been sent to the sub should be greyed out)...but guess what ? Almost no one ever does this.
I agree with you, it's just that I like to have the freedom to tweak my system the way I want.
 
TLS Guy

TLS Guy

Seriously, I have no life.
I agree with you, it's just that I like to have the freedom to tweak my system the way I want.
Part of the problem is that we have no idea what your HTPC setup is capable of and what streams it can grab and send out to a preamp. We have no idea. But you say it can send an optical or RCA digital stream. That means decoding is going to have to take place in the preamp.

Next, using Pure Direct does not result in better sound. That is a myth. I have looked at that myself and that is nonsense.

If you want to do stand alone HPF, which I don't advise, you will have to go custom.

First of all you will need a preamp or a receiver with preouts.

Then you have two options.

You can look for vintage gear and get a good analog crossover like the Crown VFX 2, or buy a new crossover from Marchand electronics. Then you will need two, two channel power amps if you use just a preamp. One two channel if you use a receiver with preouts. So you would use two power amps from the receiver and one external two channel power amp from the crossover.

Your other option is to make your own crossovers. Parts express have a good collection of digital crossover boards for DIY active speakers. So you could select one of those and a power supply and build, or buy, a case to install it, and instal appropriate terminations. To do this properly will require a fairly well equipped workshop and significant constructional skills. However it is not that difficult. I actually designed and built an active LP crossover for a set of speakers I built that had an active isobarik bass section. So I know it is possible. What I don't know is your level of skill.

However, I have to say that you are making a mountain out of the proverbial mole hill. My experience tells me you are likely to have massively lower SQ than you would if you conformed to current protocols. My hunch is that you don't have the skill sets yet to pull this off. If you had them, you would not be here asking all these questions.

When I design a system I don't go looking on forums to ask: - How to I do X. I jolly well make sure I research it, know what I am doing, draw up a practical design, and make an assessment that I have the skills to pull it off. That is the way you go about one offs. Having been down that road a time or two, and know whereof I speak.
 
isolar8001

isolar8001

Audioholic General
I agree with you, it's just that I like to have the freedom to tweak my system the way I want.
People in hell want ice water too....If you are not going to listen to anyone here, why do you keep posting ?
 
A

adrhc

Junior Audioholic
well, I try to be polite and answer the questions addressed to me
 
A

adrhc

Junior Audioholic
related to last @TLS Guy post, I’m pretty sure he knows what he is saying but is not at all what I intend to do: my solution is to use software and my computer (i.e. HTPC), my (active) subwoofer and the amp that I’ll buy. For example I don’t intend to output on optical or RCA (as @TLS Guy supposes) but optical and RCA; one output will be HPF filtered whilst the other not (it’s easy with pipewire).

UPDATE
One could replace "optical" with "USB" at the rest is the same from the software point of view.
 
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isolar8001

isolar8001

Audioholic General
related to last @TLS Guy post, I’m pretty sure he knows what he is saying but is not at all what I intend to do: my solution is to use software and my computer (i.e. HTPC), my (active) subwoofer and the amp that I’ll buy. For example I don’t intend to output on optical or RCA (as @TLS Guy supposes) but optical and RCA; one output will be HPF filtered whilst the other not (it’s easy with pipewire).
Sorry, kid...you are just hopeless with this HPF nonsense.
 
mono-bloc

mono-bloc

Full Audioholic
I try to be polite and answer the questions addressed to me
Why are people even bothering to reply to this OP, He's simply a complete waste of space, and will soon be looking for someone to blame when everything goes arse up.
 
TLS Guy

TLS Guy

Seriously, I have no life.
related to last @TLS Guy post, I’m pretty sure he knows what he is saying but is not at all what I intend to do: my solution is to use software and my computer (i.e. HTPC), my (active) subwoofer and the amp that I’ll buy. For example I don’t intend to output on optical or RCA (as @TLS Guy supposes) but optical and RCA; one output will be HPF filtered whilst the other not (it’s easy with pipewire).
You asked for a Toslink, and USB input in your first post. They are digital.

I have to say that you are eagerly pursuing the master chef of dog's diners award right now.

There is a body of knowledge required when engaging in any technical pursuit. Part of that body of knowledge is knowing the rules and guard rails. Audio and AV is no exception to this. There are set patterns of design and operation to systems. To engineer any technical undertaking you have to know these and where the guard rails are. However, you seem intent on continually banging up against the guard rails and getting a very sore head.

At this point in the game this retired professor is giving you and F grade on your course work so far.

So you need to step back and really understand the rules and constraints laid down in the body of knowledge required to engineer and build successful systems.

Your only possible excuse is that you have been misled by doing your researches in the wrong places. Unfortunately wrong information abounds. It is clear to me you have been filling your head with cod's wallop.

When you have remedied your serious educational shortcomings, I will be prepared to engage with you again. So the ball is now in your court.
 
A

adrhc

Junior Audioholic
I think at this moment the community recommended some approaches, i.e. Yamaha R-N800A or Yamaha R-N1000A, so I guess we are good for now, thank you all.

You asked for a Toslink, and USB input in your first post. They are digital.
For me, a PipeWire user, handling optical or USB is the same, I added an updated above.
 
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P

PENG

Audioholic Slumlord
I think at this moment the community recommended some approaches, i.e. Yamaha R-N800A or Yamaha R-N1000A, so I guess we are good for now, thank you all.


For me, a PipeWire user, handling optical or USB is the same, I added an updated above.
Yes, we recommended avrs, or receivers such as the R-N800 or R-N803. There is no point to pay more for the RN1000A unless you need the extra features, but it doesn't seem you do. In terms of value, the AVR solution would be the best, but if you don't like it then it wouldn't be for you.

Based on the info you provided, there isn't much other better choices out there.
 
A

adrhc

Junior Audioholic
For those willing to go with the PipeWire approach: use pw-dot to generate a diagram as below while playing some audio. You might not use EasyEffects (which is fine, you don't have to) hence you might miss its green boxes. I intend to add (to the right side) a new audio out (jack-based in my case) linked to node_id 58 (so, a new link too), in addition to the current out (i.e. optical in my case, for you could be anything, e.g. USB, jack, HDMI, etc); this new audio out will be for my subwoofer. I intend to filter the audio stream between nodes 58 and 45 (i.e. the optical out for me) such that to obtain the equivalent of an HPF; I'll use Filter-Chain or CamillaDSP.

PS: my computer (i.e. HTPC) has USB (all computers have it), HDMI, optical and jack audio out while the subwoofer has only RCA inputs, that's why I intend to use jack (at least in the early stages of implementation)

Mopidy, the left side in the diagram below, is an application playing audio from an online radio.
mopidy-pw-s.png


Below the TV is sending audio through Bluetooth; observe the processing differences (i.e. the source only).
bt-pw-s.png
 
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A

adrhc

Junior Audioholic
With this example, i.e. https://github.com/HEnquist/camilladsp/blob/master/stepbystep.md, one can implement the HPF and, as a bonus, the LPF too - basically it's what I need. On the other hand, while reading that configuration (which is pretty straightforward) I realised that a propper speakers-bass integration requires measurements, especially if this custom approach is used, to solve e.g.: delays between the speakers and the bass, differences in sensitivity, the baffle step compensation (whatever this means). This brings further complications which might be fun to solve for one having more then IT knowledge otherwise it's too much work hence the recommended stereo receiver is the easy (but expensive) path.

PS: see also the integration details with Alsa, PulseAudio or Pipewire
 
TLS Guy

TLS Guy

Seriously, I have no life.
With this example, i.e. https://github.com/HEnquist/camilladsp/blob/master/stepbystep.md, one can implement the HPF and, as a bonus, the LPF too - basically it's what I need. On the other hand, while reading that configuration (which is pretty straightforward) I realised that a propper speakers-bass integration requires measurements, especially if this custom approach is used, to solve e.g.: delays between the speakers and the bass, differences in sensitivity, the baffle step compensation (whatever this means). This brings further complications which might be fun to solve for one having more then IT knowledge otherwise it's too much work hence the recommended stereo receiver is the easy (but expensive) path.

PS: see also the integration details with Alsa, PulseAudio or Pipewire
It is clear to me that this project was way beyond your level of competence, and that is why I made the recommendations I did.

Delays are a huge issue, in both digital and analog crossover design. Delay results in phase shifts, When you get down to it delay and phase are just different ways of talking about the same issue.

Of course you have to match sensitivity, that is the easy part.

Baffle step compensation is to compensate for the fall in response below the baffle step frequency. The baffle step frequency is the frequency in which a speaker transitions from being a monopole to an omnipole. It is related to the width of the front baffle and response falls below that frequency.

It is clear to all of us that what you are attempting is beyond your skill and knowledge base.

So, I and others gave you good advice on how to use currently available practice to fulfill your goals with excellent results.

If you want to do it your way, please post back after a period of university level study.
 
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