It’s time for a new keyboard amplifier

[NosPup]

45 minutes ago, D. Gauss said:

re: volume. you need to be sending a +4 level signal to the Altos. That typically would be the balanced XLR out if your keyboard has one (yammie CP88 for example).  Otherwise if they are 1/4" unbalanced out, they are most likely at -10db level (sometimes higher), then you'll need another gain stage via a small mixer or line driver.  Headphone jacks are at speaker level which is a whole 'nuther thing and can easily overdrive/distort another downstream input without careful gain staging.

 

re: coverage. assuming you're in mono, you could always buy a 3rd speaker set them up in a tight cluster with one facing forwards, one off-axis left and one off-axis right.  seems like overkill, but pretty sure folks will hear you.

D Gauss is correct. And I should mention this is not an Alto problem. I have experienced similar with  JBL eons and QSC speakers also. 

[Reezekeys]

1 hour ago, NosPup said:

2 hours ago, D. Gauss said:

re: volume. you need to be sending a +4 level signal to the Altos.

D Gauss is correct. And I should mention this is not an Alto problem. I have experienced similar with  JBL eons and QSC speakers also. 

 

I guess the last almost 25 years of doing gigs with PPAs I've been in the Matrix then? Starting with Mackie SRM450s in 1999, then the K8s and now Altos, I've plugged unbalanced line-level sources directly in, no mixer, and when I needed the volume I simply set the speakers to mic level input, backed off on the input gain (QSCs), and blasted my ears (and others' ears) out, easily driving the speakers to their full output. Or, did somebody sneak into all my gigs when I wasn't looking and hook up a mixer to boost my signal to +4?!

[D. Gauss]

36 minutes ago, Reezekeys said:

 

I guess the last almost 25 years of doing gigs with PPAs I've been in the Matrix then? Starting with Mackie SRM450s in 1999, then the K8s and now Altos, I've plugged unbalanced line-level sources directly in, no mixer, and when I needed the volume I simply set the speakers to mic level input, backed off on the input gain, and blasted my ears (and others' ears) out, easily driving the speakers to their full output. Or, did somebody sneak into all my gigs when I wasn't looking and hook up a mixer to boost my signal to +4?!

 

By switching to mic-level, another gain stage gets added, which yes, does boost the level. Whether or not that works for you (and it seems it does) depends on how hot the level into the mic pre is and/or how much headroom the pre has before it will overload/distort, and how loud the speaker needs to be.  The topology of a lot of preamps these days can handle a wide range of input signals without crapping out. others, not so much and you'll hear that mic input crunch horribly.  Also, some people also don't like to have the volume on their keyboard itself very high (maybe halfway) so as to A) have room to turn up for solos, and/or B) reduce noise from the crappy output amplifier of the keyboard.  (i have an old yamaha keyboard that sounds like ass if the volume is set at 7 or above).  

[Reezekeys]

2 hours ago, D. Gauss said:

By switching to mic-level, another gain stage gets added

 

In the case of my K8, there's no gain stage added when switching to mic level - the mic/line switch just removes a pad from the circuit when it's set to mic. I'm not sure what's going on with the Alto's volume control, and I forgot what the rear panel of my Mackies look like! 🙂  I'm gonna guess that the input stages of these amps are all tuned for microphone levels, and the switches or pots are attenuating, so a line level signal won't overload things.

 

I do think one needs knowledge in gain staging to make a setup like mine work, but it's not that difficult. When I knew I needed that eardrum-destroying volume, I switched to mic input, put my source's output volume at 6 or 7, and started with my speakers' level controls all the way CCW, slowly turning them up as I played. If I immediately heard distortion, I knew I was overloading the inputs so I backed off the volume from my sending device. Once the sound was clean, I adjusted the volume on the speaker to as loud as I dared - louder than I thought I needed - then backed off on my source a bit to a more "normal" level, knowing I'd have some room to boost the volume a bit, for solos or whatnot. (Notice the past tense - I don't do gigs anymore where I need that kind of volume!). Of course there's more noise when the speaker was set to mic level, but there's also a lot more gain and, at least in my case, with proper gain staging the s/n was more or less the same - since my keys were coming out so much louder. Believe me, at the volume levels some of these bands I worked with played at, you're not gonna hear any of that "extra" noise!

 

This worked well for me because I'm 100% in the box - instruments, effects and eqs. All coming out a single stereo output. Given that scenario, it just made sense to connect directly to a PPA. If I had multiple keyboards I know I'd need a mixer. If I needed EQ or effects that my keyboards couldn't give me, I'd probably need a mixer. Neither of those conditions apply and that makes me happy because it's been a goal of mine to bring the least amount of gear I needed while still having a satisfying playing experience.

[stoken6]

9 hours ago, JohnDoe said:

What M-S encoder are you refeering to?

A mid-sides encoder. Mid=L+R, Sides=L-R. This is the encoding performed inside the Space Station (perhaps with a bit of special sauce on top), and is a common studio technique. 

 

9 hours ago, Reezekeys said:

Won't work, because the side-firing speaker has to have an open-back design - you want sound coming out both sides that's 180 degrees out of phase, which happens by default in the SS since the speaker cone is pushing air out one side while it's pulling on the other!

True - or at least it's not identical to the space station. (Three speakers, encoded L-R facing L, L+R facing forward, R-L facing right might do it). But I think even two speakers as I described would add some depth and motion to a point source. 

 

Cheers, Mike.

[AnotherScott]

13 hours ago, Reezekeys said:

I guess the last almost 25 years of doing gigs with PPAs I've been in the Matrix then? Starting with Mackie SRM450s in 1999, then the K8s and now Altos, I've plugged unbalanced line-level sources directly in, no mixer, and when I needed the volume I simply set the speakers to mic level input, backed off on the input gain (QSCs), and blasted my ears (and others' ears) out, easily driving the speakers to their full output. Or, did somebody sneak into all my gigs when I wasn't looking and hook up a mixer to boost my signal to +4?!

the Alto manual specifically warns against moving the knob past the "line" range and into the "mic" range if you are using a line level signal.

 

Using a PPA's mic input/level control to boost a typical line level keyboard may or may not work well. Regardless, it is not how the unit was designed to be used. I can't say I know what all the ramifications might be. Higher noise level? Altered frequency response? Higher distortion? Possible premature damage to the mic preamp? I don't know.

 

So like NosPup and D. Gauss, I've stuck with the "official" line inputs of my various PPAs, and found them to be sufficient only for relatively quiet use, and otherwise always use a small mixer in between. 

[Reezekeys]

2 hours ago, AnotherScott said:

the Alto manual specifically warns against moving the knob past the "line" range and into the "mic" range if you are using a line level signal.

 

Of course it does. My guess is that's because of users ignorant of the principles of gain staging who plug something in with the speaker's volume maxxed, then proceed to blow their ears (or the speakers, or both) out. That's easily possible if you don't know what you're doing! IMO, Alto putting that warning in their manual is akin to those labels warning you not to use a hair dryer in the bathtub.

 

Think of it this way - your signal isn't hot enough to drive the speaker to the volume you need. You put a mixer in the signal path to add gain so you can get that volume. I switch to mic level which adds gain to get that volume. We're both adding gain, you right before hitting the speaker's input and me right after. If adding gain is the only thing needed, I don't see any difference except I have one less piece of equipment to buy, carry around and hook up. Maybe your mixer has better s/n specs and puts a slightly cleaner signal into the speaker at the same resulting output level, but in the context of a gig, especially with a full band, any difference is likely to be negligible. When I switched to mic level on my K8s, I always backed off on the input knob and never heard noticeable hiss or noise while I was playing.

[PlayItLeo]

On 2/26/2023 at 10:45 AM, Reezekeys said:

As far as the other issues, it sounds like you might need to experiment with placement. Mine are vertical, not in their wedge position, in back of me on either side, on small folding footstool stands that raise them about 8 - 10" above the ground. I'm on the side of the stage, angled in a bit. The idea is for the speakers to cover me, the bandstand, then as much of the audience as possible. The speakers' horns, being below my ear level and not pointed upwards towards me (as they would be in wedge orientation) means I can push them louder without blasting my ears - which gets more sound out onto the bandstand and the room. It's always going to be a compromise - but I try to make sure I'm comfortable and can hear myself correctly with everyone else. I've been doing it this way for years and have rarely heard anyone tell me my keys were too loud or too soft. Good luck!

Great example of a nice stage set-up, thanks Reezekeys! I am looking into the TS308/310/408/410 set up for myself.  

But I would ask with your set-up, can the band here your monitors well, just assuming they are also getting a bit of you from the FOH into their own monitors?

[Synthaholic]

On 2/5/2023 at 5:58 PM, Doug Robinson said:

To make things worse, I’m getting distortion from time to time now and because I live in central Mexico, sending it to a qualified repair person is a huge hassle and very expensive.

New to this thread, but re-reading this from the opening post. If you're pretty sure you don't have a blown speaker or tweeter, that chassis comes out and you can send it off for repairs for I believe $125, which was the quote I got from Aspen's daughter a few months ago. It used to be $75, and I've sent 2 chassis over the years. She has turned it over to someone in NY, IIRC. I know this doesn't solve the issue of how it sounds when it's too close, but maybe in those cramped situations you could pair it with another speaker for bottom end while turning the SS3 down a bit. That's what I do, either with one of my JBL EON 510 or my EV ZLX, like in this photo that I have posted here before. I still get the "bloom" from the SS3, from the thin plywood, and the EV handles the bottom end really well for smaller spaces.

 

[Reezekeys]

1 hour ago, PlayItLeo said:

Great example of a nice stage set-up, thanks Reezekeys! I am looking into the TS308/310/408/410 set up for myself.  

But I would ask with your set-up, can the band here your monitors well, just assuming they are also getting a bit of you from the FOH into their own monitors?

 

There's almost never a PA system or monitors at the gigs I do near me; they're mostly in restaurants or other small venues without PAs. If there's a vocalist on the gig, they bring their own PA, but it's only for themselves – no instruments are going through it. (When I'm on the road with the band that actually helps pay my mortgage, I use in-ears).

 

I always set up on a side of the stage and angle myself towards the center. Then I try to spread the angle between the two speakers out a bit, to cover as much area as possible while still getting a good dose of myself. My K8s have a pretty wide horizontal dispersion (105°) while my Altos are a  more modest 90° (I think smaller-woofered speakers generally have a wider coverage angle). Just looking at my amateur drawing attempt below, I can tell I probably have more coverage than what I indicated but you get the idea - the rest of the band hears me pretty good, and because my speakers are below ear level (on footstools, as I mentioned in my previous post), I can push them harder so the audience hears me OK as well. I've been doing it like this since I went stereo with Mackie SRM450s close to 25 years ago and I haven't heard any complaints yet – and most of the musicians I know like to complain!

[Doug Robinson]

Just a quick update… I did two gigs with the Alto TS 410 speakers. Even with a long sound check, even using the stands on one of the gigs, I could not feel relaxed and happy with the system. It’s so directional.  If I angle it too much towards the drummer, he was upset. That forced me to angle it a little  bit back towards me and then it was just too in my face. for the last gig, I ran a line out from a sub mixer to the house, and just use the altos as my own personal monitors but I couldn’t get far enough away from them to feel comfortable.  And if I did get them far away from me, I couldn’t really hear that well.

 

Happily, a friend of mine, who is a keyboard player was in the audience and asked how I liked them, and when I told him I was returning them, he said, let me buy them from you. That’s happening, now I have to go back to my space station.

[Doug Robinson]

Thank you everyone for your help and your words of advice. There’s a lot of really good information. I guess I’m just spoiled by what I like about the space station. Oh well!