Double Bass Educate me about using Impulse Response files…

[Anthony White]

Can anyone educate me about using Impulse Response files, especially in either a live or practice setting, without having to load a DAW and run everything through the DAW?

In particular, another thread referred to 3-Sigma-Audio having a set of 12 double bass impulse response files. Looking at the website, it seems they are designed for use in a DAW.

I have an order in with Thomann for a Yamaha SLB-300, but it’s been three months, and they’ve just told me it will be at least another two months before they are in stock.

I also seriously considered an MK Jazz-passive. It looks better built than the Yamaha, but the Yamaha has the built in Impulse Response modelling, by Yamaha, who I believe will do a great job. (I can’t try either before finalising purchase.) But the Yamaha, the Impulse Response is baked in, and will eventually be out-of-date. With an external Impulse Response pedal, I imagine I could take the piezo output from the MK and then update the pedal as technology improves. It seems more buy-it-for-life for the core instrument.

So, is there a floor pedal I can use, eg IK Multimedia ToneX, with an Electric Upright, say MK, that will give me the Impulse Response modelling equivalent to the Yamaha, but with future flexibility, and that after initial set-up is plug-and-play?

I really want to be able to go into my front room, pick up my electric-upright, switch on a pedal/preamp, and play through headphones. Or, take the same electric-upright to a gig, assemble, plug in the pedal/preamp to the backline, and play.

 

[Anthony White]

@Mojo34 - You talked about this on another thread regarding a Torpedo Cab M and the 3-Sigma-Audio IR Files… is what I’m asking about above what you are doing?

 

[Hummergeist]

I’ve tried a few IRs in software and pedals such as the Boss GT1000 Core and Torpedo. I like them when playing bass on its own without even a backing track, but I just don’t like them in any kind of mix. YMMV.

 

[Mojo34]

QUOTE="Anthony White, post: 27754856, member: 182624"]@Mojo34 - You talked about this on another thread regarding a Torpedo Cab M and the 3-Sigma-Audio IR Files… is what I’m asking about above what you are doing?[/QUOTE]
Interestingly enough, I apparently revived a thread about the Zeta upright bass, because 3 Sigma did an update to their Acoustic Bass IR offering, and they specifically included an option for this pickup system. I think that's one of the main factors to good sound, but it is now very satisfying pizz'd and bowed. Amazingly so. I suppose I could do a cell phone recording and post it to SoundCloud.
I rarely use my computer for any of this stuff. The Two Notes Cab M is a great live tool -- just play into a neutral amplified speaker or mixer. Even when I use my DAW, I still come in from the Cab M as if it were a mic'd cabinet.
I would consider not getting the bass with a built-in IR, as there would be no easy way to change it. With the Cab M and Sigma (and others), you can experiment to your heart's content based on your own equipment.
I had literally never been satisfied with my upright bass sound amplified until the day before yesterday. The pedalboard is also used for electric bass. I just switch the Cab M to an Ampeg simulation and off we go...

 

[Anthony White]

That’s cool, thank you.

So how does it work? You download the IR files to the pedal - presumably USB-C between the pedal and a laptop - and then just play through it like a preamp?
Does it need a specific type of input to give best results? Are they good enough to give an electric bass guitar a more-or-less convincing upright sound?
How well do they sound with a bow? Are they pizz specific, or do the maps work for Arco as well?
Are there other plug-in designers than 3-Sigma who have good IR files?

 

[themickster]

Darkglass Microtubules B7K Ultra v2 can run IRs

 

[kkenda11]

Line 6 Helix and Shift Line (Olympic MkIIIs and CabZone Bass) work well for loading IRs.
Shift-Line also has a set of free IR files on their site that I really like for Bass Guitar.

I've messed around with using IRs with my MK EUB, but haven't been playing the EUB much lately. Sometimes they can sound nice, though it is tricky to get something that sounds totally natural.

For me, IRs are really great for simulating a cabinet when you aren't using a real cabinet -- for example when recording straight into an interface or using headphones for practice. I had less satisfaction with trying to use them to fundamentally alter the sound (for example to make a pickup sound more acoustic). If I wanted to go down that path I think I'd wait for the ToneDexter II.

 

[Mojo34]

Yes, you load the IRs into the pedal via software on your computer, with a USB connection. I happen to be using a preamp pedal, I'm not 100% sure what it's like without that. It might help boost the signal.
In this case, with EUB impulse responses, I find they fundamentally provide an acoustic upright bass sound in my situation. It does not sound like an amplified bass running through a bass amp. Also, the IRs don't give compelling UB sound through an electric bass guitar, though 3 Sigma includes files for electric bass guitar. The sound on the EUB is motivating me to propose songs for my band that we can play around this configuration, but I love it with a bow. What's the best way to send a sound sample here, without going through a DAW?

 

[DoubleMIDI]

Impulse responses deliver an acoustic bass sound from the electric output of a pickup.
Since the electrical output can vary a lot with different pickups, they typically work best with the pickup they were taken off. There was some discussion about transferring an impulse response analysed from an acoustic bass to an EUB and common sense was it sounded best with the same type of pickup that the acoustic bass had when analysed.
Strings have the normal influence on sound that they have purely acoustical too.
Since bass guitar strings are very different in construction, length and sound than double bass strings, the normal acoustic double bass impulse responses don‘t give an acoustic double bass sound, but might move a bit into that direction.

An impulse response is basically a filter over the whole frequency range, depending on the length of the IR with a bit of resonance. But the filter itself is not resonant, it just keeps it for the time length of the IR.
For the experts: it is a FIR (finite impulse response) filter not an IIR (infinite impulse response) filter.

 

[bradd]

I've run the 3sigma files into a shift line Olympic and it works somewhat well. The problem with some of these IR loaders is sample length. A cab IR is much shorter because you don't want much of the room sound in the sample, but an acoustic instrument needs that room sound. Look for a loader that has a 200 m/s sample length or longer for best results.

 

[Happy Steve]

I have used 3sigma IRs as detailed EQ profiles.. plus I create my own / modify them in a DAW (Reaper) for fine tuning.
To avoid repeating myself or cross-posting please refer to :
Impulse response Loader
and YAMAHA EUB Megathread
the NU-X loaders are reasonably priced and could be a good platform for trying out IRs with your existing equipment.
I have used the Optima Air, the NSS-3 and -4 and the Mighty plug pro models with IRs.
I only used the Optima Air live with my URB. I am ready to use my SLB-200 with my NSS-4 Pulse IR loader when the right gig turns up.
Best wishes,Steve

 

[Anthony White]

Thanks for all these replies. They are really helpful. I’ve been reading a lot as well, and think I am starting to understand better. So please treat the below as the question - am I understanding this correctly?

So the Impulse Response file applies effectively an envelope of EQ to the existing input signal, changing the way the input signal sounds. Maximum length of an impulse response file is 500m/s. But it doesn’t respond over time the way, say, a digital reverb does.

The attack and decay of the input signal, the note, will remain the same because it is determined by the instrument itself. An acoustic instrument will have a harder attack and a faster decay - relative to a solid body instrument - as the wave form of the string is damped as the energy moves the acoustic soundboard of the instrument.

I think that sounds right.
Does anyone know specifically what the software in the Yamaha SBL300 is doing?

I have an MK Jazz on order now; I’m finalising the details with Mirko. It has the floating/suspended soundboard to help dissipate the energy of the string in an acoustic-approximating way. I’ll also start with Evan Pirazzi strings, which have the synthetic core that also damps the sustain of the instrument.

Ultimately, I’m not looking for a perfect simulacrum of an acoustic bass. Just ‘good enough’. I live in a 120-year-old apartment in Berlin, with noise sensitive downstairs neighbours, and I already have three energetic children. I need an instrument that is good enough, with an interesting enough sound to practice on, without disturbing family and neighbours.

 

[Martin Spure]

Congrats on the new MK I’m sure you’ll love it.

I have Evah mediums on my MK Studio, which does not have the resonance chamber like the MK Jazz. Instead the bridge is sitting on a solid block with the proprietary pickup embedded. I must say, the tone I can get from just the pickup going through my preamp (Acoustic Box II) sounds better than any piezo’s I have ever tried on my ‘real’ double bass, for some reason. I’d highly suggest you try the built in pickup with some parametric EQ, if possible. You can get surprisingly close with that alone.

I was very interested in the ToneDexter for the same reasons as you, but I must admit I never heard demo’s that convinced me for DB/EUB. I don’t like the sound of the Yamaha SLB 300, even with it’s IR setting, either. But that’s just a personal taste thing, I guess.

You might already know this video, but here’s an interesting little test from Hervé Jeanne:

 

[hensonbass]

I have an order in with Thomann for a Yamaha SLB-300, but it’s been three months, and they’ve just told me it will be at least another two months before they are in stock.

I also seriously considered an MK Jazz-passive. It looks better built than the Yamaha, but the Yamaha has the built in Impulse Response modelling, by Yamaha, who I believe will do a great job. (I can’t try either before finalising purchase.) But the Yamaha, the Impulse Response is baked in, and will eventually be out-of-date. With an external Impulse Response pedal, I imagine I could take the piezo output from the MK and then update the pedal as technology improves. It seems more buy-it-for-life for the core instrument.

I own a SLB-300 and I would not put a lot of faith in the IR modeling technology in this instrument.

My personal experience has been
met with much frustration due to the pick up system sounding very weak and out of phase and just unreliable. I have also heard from other SLB-300 owners that this has been their experience as well.

I like the Yamaha bass ergonomics and it does play easy. However, in order to make it usable for me I had to install a Realist Lifeline pick up in the bridge.

Considering that I bought the instrument three years ago they might have fixed these issues or maybe I just happen to have a defective pick up system. I never had any luck trying to contact a service representative at Yamaha.

Your profile said that you lived in Germany. I would look into this instrument as well: Double bass - Alter Ego

I played one many years ago and it was shocking how good it sounded.

Good luck with your search!

 

[DoubleMIDI]

The FIR filter of an IR can model resonances, but only limited in time over the length of the IR whereas an IIR filter has a feedback that can deliver an infinite response, but is very difficult to model and can easily produce an internal feedback.

If the length of the FIR is several seconds long, an IR can model room resonances and reverb. But it is computationally expensive (the more the longer the IR is) and models one source to one listening point, both fixed in the room.

 

[Anthony White]

the tone I can get from just the pickup going through my preamp (Acoustic Box II) sounds better than any piezo’s I have ever tried on my ‘real’ double bass, for some reason. I’d highly suggest you try the built in pickup with some parametric EQ, if possible. You can get surprisingly close with that alone.

That Acoustic Box II looks nice, and with built in reverb and delay… I have a Grace Felix, and have been thinking about getting a nice external reverb/delay unit to give the MK some air and room sound through headphones.

So how (approximately) do you set up your para-EQ?

 

[Martin Spure]

I like the Acoustic Box very much. I haven’t used the delays or reverbs much, or indeed played around with the settings, so I can’t really say if it’ll suit your purpose. The effects are sort of OK, I guess. But I’m used to working with much better reverbs in Logic Pro, so I’m quite picky when it comes to reverbs in pedal form. A short delay may give you that roomy sound in the cans. Reverbs on bass tend to cut some low end and get ‘mushy’ quickly; except maybe for exposed medium/high register passages.

I’ve attached a picture of my ‘starting point’ EQ, which I keep a copy of on my phone as well. Mind you, I prefer a quite dark old school sound with a short decay; no ‘week-long’ sustain for me, so your tone preference may be different, thus my settings may be too dark. But with these settings I’ve managed to kill most of the piezo quack around 700hz’ish, by using the channel 1 para EQ to cut that frequency even before the signal reaches the 3 band para EQ. This makes it a lot easier to dial in the tone with the 3 band EQ. You’ll see that I use all the bands to cut frequencies. No boosting. These settings works quite well in the cans, too.

 

[Anthony White]

So my MK Jazz arrived a week and a half ago, and I have been experimenting with Impulse Response, as well as EQ and preamp and reverb.

Firstly, a little on my use-case. I bought this specifically for practice, and to practice through headphones. I currently live in a 120 year-old apartment in Berlin, with no sound insulation between floors.

So I am really interested in a good sound for practicing through headphones. Sure, I could practice without a ‘good sound’, but if it isn’t enjoyable, it’s going to be harder to maintain motivation.

My current setup for trying this out has been Bass -> FDeck HPF-pre -> TC IR Loader -> TC HOF Reverb -> Grace Felix -> then into a Rolls Mini-mixer that I use to put all of my bass, piano, and iPad into a pair of DT990s or DT770s.

I bought two pre-recorded IR packs from 3-Sigma-Audio. On the samples, one sounded like a bright, modern bass, the other like a darker, older bass. (I tried the modern once, and switched straight to the darker.)

And how does it go? It’s … interesting. I’m ambivalent.

First, Pizz:
On one hand, with a flat EQ, I can hit the IR pedal to begin the IR, and it really does sound suddenly acoustic. The piezo quack is suddenly tamed, like a good 700 Hz cut. And that ‘air’ in the sound that people talk about seeking with microphones is there. More technically, it seems like quite a lot of additional high-frequency information is brought out of the piezo signal. In fact, too much high-frequency information is emphasised, and I find I need to cut it back with a high shelving EQ. If I’m playing on the D and G strings, it’s really quite a good sound, and it would be worth pursuing.

But on the other hand, with the IR it seems to lose some bottom end information in a way that makes the E string feel cold and boxy. It’s like an EQ rolling off too much bottom end, and I’m unable to get it back boosting EQ.

Second, Arco:
I don’t like it at all. I actually can’t tell you why. When I have some more time I might put something through a DAW and look at a spectrum graph. With the IR engaged, I can get something that is passable…

But I get a much better result with the IR loader disengaged, a dramatic 12dB 700Hz notch on the Felix para-eq, and and then rolling of some of the lows and the highs with the Felix shelving eq.

I was trying for a little while switching between IR-Loader sound for pizz, and eq’d sound for Arco. I thought that might be worthwhile, and the fiddliness was something I could deal with. But I’ve thought a little more about all the functionality in the Felix.

So, my current preference:

The HPF of the FDeck HPF-Pre set to something circa 45Hz (the HPF isn’t marked, so this is a guess. It’s probably rolling a couple dB off the open E string). Then the Felix first knob set to ‘notch’ rather than ‘HPF’, and that notch set at 700 Hz to take out the piezo quack. The bass Eq (shelving at 125 Hz) is rolled off maybe 5-6 dB. Then, the mid-para EQ set to the higher of the two frequency sets. I’m centring the EQ at about 3.6 kHz, the Q is nearly as wide as it will go, and then I’m cutting 12 dB. And the high shelving (at 2 kHz) is rolled off 12 dB as well. Now, I think what is happening, is that I’m using the Mid-para (-12 dB) and the High-shelving (also -12 dB) to roll off a total of 24 dB from the top end frequency information, above something like 2 kHz. I’m effectively making it into a 2 kHz Low Pass Filter. Can anyone confirm that this is most likely the thing that is happening?

And I think one of the reasons that this is working is that the piezo in the MK Jazz is embedded in the soundboard, and it is really hot and picks up a lot of extra high-end vibration/sound information that is never heard playing an instrument acoustically. Fingers on strings, rubbing, scratching, touching the fingerboard… And remember, I’m running through studio headphones, so it is surgically accurate and piped straight into my ears. It’s quite possibly not noticeable if running through an amp with no tweeter.

The sound I’m getting this way is quite good both Arco and Pizz. Playing along with recordings it sits really well in a mix, and I imagine it would do so in a live setting as well.

It does, though, rather mean that I don’t have any further EQ flexibility with the Felix. What I’d quite like to do is experiment with a gentle EQ boost in that 1 kHz - 2kHz region, and see if that will add a little more ‘air’ to the sound. If what I think is happening above (summing the two EQ cuts to add to 24 dB above 2 kHz) I’m a little bit tempted to try a Low Pass Filter, to see where in the 2 kHz-3 kHz region I want to completely cut. There are a few options out there.

 

[Anthony White]

Reverb - And it’s moving some way from the Impulse Response discussion, but the reverb is a useful addition. It’s really nice when practicing Arco through headphones - just a Room Reverb, with a moderately fast decay, really just to simulate being in an open room father than with headphone clamped to my head. Quite nice practicing solo Pizz as well, but the reverb starts to get in the way when playing along with recordings.

TC pedal have what they call ‘ToneMaps’, which are user defined and uploaded models of whatever the pedal effect is; reverb in this case. I’m going to look at that sometime and see if I can build a reverb with both a low-cut and a high-cut that works for double bass without getting muddy.