Looking for advice with digital organ audio

[njsmk]

Hi, first-time poster and audio beginner here. I have a slightly unusual requirement that I have been researching for awhile and am looking for some expert input into. Thanks in advance for any assistance, I appreciate the generosity of any time and effort taken to respond.

As background, I am a musician currently building a digital organ at home. It uses Hauptwerk software to play real organ samples using midi key and pedal boards. These sample sets are generally made up of 3 stereo sets - one recorded up close to the pipes, a middle distance that captures both direct sound and acoustic, and a rear set that captures primarily the acoustic. A typical audio setup will include at least 6 channels - two or more nearfield monitors to handle the close up perspective and a stereo pair (of whatever) for each of the more diffuse perspectives. Generally there is a sub in there as most larger organs sound down to 16Hz. Hauptwerk includes a pretty full-featured mixer for controlling output and routing.

I've invested a fair bit into building the instrument, so I am limiting myself to the $3,000-$4,000 range to complete the initial audio system, with the ambition to improve components over the next few years.

The performance room is 3.3m x 4.2m with a ceiling height of 2.5m, that I plan to acoustically treat as required. Starting with the audio interface, I already have a Focusrite 18i20 kicking about which I figured to use. To play the rear and the middle distance sets, I was thinking about 2 stereo pairs of Elac DBR62s. The rear pair will be at the back of the room facing the player's back, the middle channels will be to the left and right next to the instrument, angled in. For the close-up, direct stereo sample, I was looking at the Kali IN-6, planning to position them within a meter either side of the instrument console. I've also been eyeing up the SVS SB3000 to handle the low end.

I was thinking the Elacs because of reviews - they're affordable, apparently flat, good low end, and dispersion seems desirable for their placement. Most important, my wife doesn't object to their aesthetic, whereas a full room of Kali monitors was not looked on favourably. I have no idea about Amps, but figured the reviews on this site would be a place to start. I'd shortlisted TOPPING PA5 on this basis; I believe I will need 2 of these. Are they appropriate, given my use case?

In terms of volume, the instrument will probably never be played super loud. IRL a pipe organ on full will have 90-100 dB SPL A-weighted out in the building. I'll almost always be quieter than that for the sake of family and neighbours.

Betraying my naivety here, but:

- Are the speakers, sub and amp choices "sound"?
- Should I be mixing the active and passive speakers, and different brands?
- Is my assumption that I take a stereo channel from the interface to an amp then to the passives the best way to wire this? I believe I can handle crossover for the sub channel in the Hauptwerk mixer.

Any suggestions on putting this all together, or improving within the budget are most welcome.

 

[mdlr11]

I'm investigating adding Hauptwerk to my Allen digital organ and have a few thoughts and questions. First, I don't think there's any problem with mixing powered and passive speakers; it will only change what kind of cables you run and how many separate amplifiers you'll need. I expect you will not need very much amp power per channel, probably well less than 100W, since you have only a small space to fill and not a cathedral. Second thought is about the sub - I am using an SVS PB2000 for my Allen organ, since I didn't have room for Allen's big speakers in my living room. The SB3000 should work just fine and perhaps better than my PB2000. The PB2000 drops off rapidly below its port frequency around 20 Hz, and it has a bit of a peak around there, especially in my room. I needed to adjust the Allen's 32' stops to pull down several notes around low Eb to tame that peak, and then needed to boost the lowest notes to compensate for the rolloff below 20 Hz. You may need to do some similar adjustments, but the SB3000 is fairly smooth in its rolloff and you shouldn't have to compensate as much as I did.

Mixing speaker types may be a bad idea. I know that with my Allen, their reverb washes across all the main channels, so if you have a stop coming from one speaker for the direct sound and then you hear the reverb tail coming out of a different brand of speaker, it can sound strange. It all depends on how sonically matched the speakers are, and it's really hard to know that without trying it. I think it would be safer to pick one model and use that same kind of speaker everywhere. Then any coloration the speaker introduces is going to be consistent no matter what part of your virtual "room" it's reproducing.

The one conundrum I'm running into and which I think you will hit as well is that Hauptwerk does not seem to have any actual audio crossover capabilities. You can route specific notes of specific ranks to a dedicated bass channel, but that's nowhere near the same thing. A 32' Contre Violone has plenty of harmonics that reach far above typical subwoofer frequencies, so sending the lowest octave of that stop to the subwoofer won't sound right. You need a true audio crossover that takes everything below your speakers' cutoff frequencies and routes all of them to the sub. If you mix speaker types like you mentioned, then you'll actually need different crossover frequencies for each channel.

I'm struggling to figure out how to do this. It seems like there are a few options. First, I have seen some talk of using a DAW downstream of Hauptwerk to do this all in software before the audio leaves the computer. As long as that doesn't take much CPU power, I like that approach, but I can't find any instructions on how to set it up. The second approach is to try to do it in your audio interface, since some of them have DSPs built in. Unfortunately, I can find ways to EQ each channel, but I can't find any way to do a crossover. The third approach I'm investigating is to throw more equipment downstream of the audio interface, like a MiniDSP, a pro audio crossover box, or even something cheap like a Rolls SX21. That won't be as flexible as a software or DSP crossover, but it would be simpler to get running.

I hope others here who are more knowledgeable can help us both figure these things out!

 

[Chrispy]

Somewhat depends on your extension and spl goals....

 

[DonH56]

I would look at pro speakers for performance gear, and consider getting a small'ish PA system rather than a consumer stereo system. In the U.S.A. I would call Sweetwater Sound. Given your metric units, guessing you are overseas? Check out your local pro sound stores.

Here is a link to a quick search at Sweetwater: https://www.sweetwater.com/c525--Keyboard_Amplifiers

 

[mdlr11]

I would look at pro speakers for performance gear, and consider getting a small'ish PA system rather than a consumer stereo system. In the U.S.A. I would call Sweetwater Sound. Given your metric units, guessing you are overseas? Check out your local pro sound stores.

Here is a link to a quick search at Sweetwater: https://www.sweetwater.com/c525--Keyboard_Amplifiers

Why a PA system? We don't need the SPL that PA systems are optimized for. Wouldn't home speakers tend to provide better sound quality, even if they can't get as loud?

Now if you're referring to amps or audio interfaces, then yes, the pro stuff makes sense. Digital organs need lots of channels of audio, unlike typical home stereo systems.

 

[DonH56]

Why a PA system? We don't need the SPL that PA systems are optimized for. Wouldn't home speakers tend to provide better sound quality, even if they can't get as loud?

Now if you're referring to amps or audio interfaces, then yes, the pro stuff makes sense. Digital organs need lots of channels of audio, unlike typical home stereo systems.

I do not play keyboards (or barely) but my wife and many friends do and have over the years. IME typical consumer stereo speakers are simply not up to the task of handling the power required for performance, even just a keyboard in a room. You (or maybe just me, my wife, and friends) end up running a little louder and much more constant power through the speakers from a keyboard compared to typical recorded music. May be different for you, but just a keyboard in a room averaged higher power than playing a recording. I have seen a lot of blown speakers (and amps) over the years when they were used as keyboard (or guitar) speakers. It is not that peak SPL was higher, just that the average power level was much higher and more constant compared to listening to a record or CD.

Home speakers may or may not provide better sound quality, depends upon the speaker, but in this case we are talking production and not reproduction so the pro stuff seems to fit the application unless I misunderstood (quite possible!)

Way back when I had a system set up for my wife's keyboard I used a dbx crossover to a sub patched through the effects loop of the keyboard amp. These days she doesn't use the keyboard much, prefers her grand piano, so we have a little Roland mini-monitor pair.

All IME, YMMV! - Don

 

[NTK]

I know nothing about organs (digital or otherwise), and went to the Allen Organs company website and looked around. Extremely fascinating instruments, not at all what I expected. One of the videos in their YT channel.

 

[dualazmak]

Hello and welcome to ASR!

Excellent reproduction of pipe-organ sound in nice HiFi sound quality at home audio listening room has been one of the main themes/challenges in my DSP-based multichannel multi-SP-driver multi-amplifier audio system/setup. You would please refer to my specific post #782 on my multichannel project thread.
- Reproduction and listening/hearing/feeling sensations to 16 Hz (organ) sound with my DSP-based multichannel multi-SP-driver multi-amplifier fully active stereo audio system having big-heavy active L&R sub-woofers: #782

The YouTube video clip I referred in above post #782 which has distinct 16 Hz huge pipe-tone is actually played by Hauptwerk virtual organ as you described (ref. here #641 on my project thread and here #394 on thread "BASS!").

I agree with @mdlr11's point in above his post #5 that you may better to avoid PA system but go into HiFi home audio gears in multichannel active setup for better total sound quality in home audio setup.

Of course you need excellent rather heavy-large L&R subwoofers (active or passive, driven by dedicated powerful high-damping factor amplifiers). Furthermore, let me emphasize that you also need not only excellent woofers plus midrange but also nice tweeters plus super-tweeters all in multichannel configuration driven directly (with no LCR network) by each of the dedicated amplifiers. I recently intensively discussed this aspect, i.e. high-Fq sound reproduction of organ music, in my post #32 through post #34 on my another thread "Music for Testing Treble (High Frequency) Sound".

In DSP-based multichannel audio setup, you can choose multiple amplifiers (not necessarily expensive ones) in policy of "right-person-in-right-place"; you do not need powerful amplifiers for tweeters and super-tweeters, but you need small-power high-S/N low-distortion amps for them. Please also refer to this post;
- Even Greg Timbers uses "reasonable and budget" Pioneer Elite A-20 for compression drivers (super tweeters) in his extraordinary expensive multichannel stereo system with JBL Everest DD67000 which he himself designed and developed: #435

I assume that details of the latest system setup (ref. here #774) of my DSP-based multichannel multi-SP-driver multi-amplifier audio system would be of your interest and reference. I do hope much good lucks in your home audio project!

Edit:
Please be reminded that not only Fq-SPL response over 12 Hz - 22 kHz, but also 0.1 msec precision time alignment between all of the SP drivers are critically important for nice reproduction of pipe organ sound (ref. here #520 and here #687).

 

[Julf]

Edit:
Please be reminded that not only Fq-SPL response over 12 Hz - 22 kHz, but also 0.1 msec precision time alignment between all of the SP drivers are critically important for nice reproduction of pipe organ sound (ref. here #520 and here #687).

Kind of funny considering real church organs come nowhere near that...

 

[dualazmak]

Kind of funny considering real church organs come nowhere near that...

Yes, I well understand what you mean.

My point of "precision time alignment between all the SP drivers", however, is for accurate reproduction of excellently recorded pipe organ tracks/albums such as the one I referred in my post here.

Spoiler

 

[mdlr11]

Somewhat depends on your extension and spl goals....

As the OP mentioned, a real pipe organ is only going to be around 90-100 dBA in the room, and I find that I usually run my organ only around 85 dBA at its loudest. So per-speaker volume is not going to be all that great. It would be at most comparable to a typical home stereo system's output when listening as 'foreground" music and not background (as my wife puts it).

 

[mdlr11]

...much more constant power through the speakers from a keyboard compared to typical recorded music.

You have a good point here, although I disagree about using PA speakers. Organ music generates much more constant low bass energy than most other kinds of music, so you need a sub that can handle continuous output down very low. For example, I have a great recording of Bach's Toccata in F major at the Wanamaker Organ in Philly, and the opening pages have a pedal point on low F, and then another page or two on the lowest C. Those are around 20 Hz and 16 Hz, respectively, and the notes play for about 30 seconds straight. Another track on that CD has low bass notes like that for minutes on end. Wimpy home theater subs aren't going to be able to handle that kind of sustained load without overheating.
Fortunately, my SVS PB2000 and my Rythmik F18 both seem to be able to handle this kind of load without problems, at least in my house.

 

[jcarys]

I've run all my keyboards through a standard home receiver and speakers for decades. There's nothing unusual about the sound coming from them compared to any other music source. I just grab whatever is not in my main system, and repurpose them for the keyboard. Your model choices all look solid to me. I would not mix passive and active speakers, just for simplicity. Choose one and go with it. I also would not mix brands if you don't need to. Find speakers that sound good to you and your wife will tolerate and go for it.

 

[DonH56]

You have a good point here, although I disagree about using PA speakers. Organ music generates much more constant low bass energy than most other kinds of music, so you need a sub that can handle continuous output down very low. For example, I have a great recording of Bach's Toccata in F major at the Wanamaker Organ in Philly, and the opening pages have a pedal point on low F, and then another page or two on the lowest C. Those are around 20 Hz and 16 Hz, respectively, and the notes play for about 30 seconds straight. Another track on that CD has low bass notes like that for minutes on end. Wimpy home theater subs aren't going to be able to handle that kind of sustained load without overheating.
Fortunately, my SVS PB2000 and my Rythmik F18 both seem to be able to handle this kind of load without problems, at least in my house.

IME, which clearly matches nobody else's here, it wasn't really the deep bass that was the problem, but the lower midrange up. Depending upon the organ, low-frequency percussives such as pianos generate (e.g. from hammers hitting strings, or emulated) are less prominent, and the lowest pedals are rarely used. Very few organs have 64' pipes, air or electronic (though I'd guess more electronic since it's easy for them, and of course closed pipes are half the length of open for the same pitch). That said, your recordings are among the reasons organs can tax speakers (subs).

My experience comes from people practicing and playing at home or small venues using regular consumer speakers. Sure no problem if you keep the volume down, but playing is fairly constant and usually (again IME) at greater average power than typical listening because you are constantly playing. Practicing tends to be at higher average SPL than playing back music so you can hear what you are playing and listen for flaws, nuances, etc. An hour of practice yields greater net power than an hour of typical music, albeit not an organ CD. This is based on my experience with musicians, my measurements (from the primordial past), and all that jazz. I rarely saw sub (or tweeter) failures, it was usually the midrange driver that died.

I suspect my current speaker system (Revel/Rythmik) would do OK; some of my lesser systems, not so much. But if the level really is kept low enough to be within the speaker's (midrange driver's) continuous power rating it should work. I am biased by many memories of shot drivers from musicians using home stereos for organ and keyboard practice. One big counter argument is that my wife has for many years practiced the keyboard for shows using small monitors and they have not blown up yet.

One question I have is exactly what components are needed to fit within the OP's $3k~$4k budget? Speakers, how many, amps, preamps/mixers, ???

 

[mdlr11]

Regarding the audio crossover issue I raised above, it appears that Hauptwerk has a quite capable mixer built into it, although it does not do any EQ. However, the mixer alone will allow you to create a mixdown of all the channels, and you can feed that to your subwoofer. The ideal solution would also include a HPF for all the main channels which is matched to the LPF settings on your subwoofer, and it looks like some audio interfaces support that, but you'd have to check if your Focusrite provides that.