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#1874292 - 01/16/08 07:14 PM The Stereo Keyboard Amp Thread
Kayvon Offline
Gold Member

Registered: 05/03/05
Posts: 566
Loc: London
Since there's a great collation of information in another thread about powered PA style speakers I thought i'd start a new thread to do with stereo keyboard amps as there's just been three new models released to coincide with Namm 2008.

Feel free to talk about the effectiveness of different stereo combo amp designs and also the issue of keyboard patches needing any special programming/editing to work effectively with said designs.

I'll start off by posting specs of the newest released amps from Roland, Motionsound and Groovetubes.

Thanks to Jazz+ for the idea of this type of thread.

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KC Island
#1874294 - 01/16/08 07:19 PM Re: The Stereo Keyboard Amp Thread [Re: Kayvon]
Kayvon Offline
Gold Member

Registered: 05/03/05
Posts: 566
Loc: London
Roland SA-1000

Main Unit
Rated Power Output 350 W (75 W x 2 + SUBWOOFER 200 W)

Nominal Input Level (1 kHz) INPUT (MIC): -50 dBu
INPUT (KEYBOARD): -20 dBu
INPUT (AUDIO): -20 dBu
STEREO LINK INPUT: 0 dBu

Nominal Output Level (1 kHz) BALANCED OUT: +4 dBu
STEREO LINK OUTPUT: 0 dBu


Speakers 16 cm + Tweeter (Coaxial, 2-way) x 2
6.5 inches + Tweeter (Coaxial, 2-way) x 2

Input Controls MIC: MIC Button, Input VOLUME Knob, REVERB Knob, ANTI-FEEDBACK Button (ON/OFF), ANTI-FEEDBACK AUTO Button
KEYBOARD1, 2: Input VOLUME Knob
AUDIO: Input VOLUME Knob

Master Controls Equalizer: LOW Knob, MIDDLE Knob, HIGH Knob
ORGAN ENHANCE Button
AMBIENCE Button
MASTER VOLUME Knob
PHONES VOLUME Knob

Switches POWER Switch
GND LIFT Switch

Indicators MIC ON, MIC OFF, ANTI-FEEDBACK ON/OFF, ANTI-FEEDBACK AUTO LEVEL METER, POWER

Connectors MIC INPUT Jacks (XLR type, 1/4" TRS phone type)
KEYBOARD1, 2 INPUT Jacks (L/MONO, R) (1/4" phone type x 2)
AUDIO INPUT Jacks (L, R) (RCA phono type)
LINE OUT Jacks (L, R) (XLR type)
STEREO LINK IN Jack (1/4" phone type)
STEREO LINK OUT Jacks (R) (1/4" phone type)
PHONES Jack (Stereo 1/4" phone type)
SUBWOOFER OUT Jack (1/4" phone type)

Power Supply AC 117 V, AC 220 V, AC 230 V, AC 240 V (50/60 Hz)

Power Consumption 94 W
Subwoofer Unit
Speaker 30 cm / 12 inches

Nominal Impedance 4 ohms

Connection INPUT Jack (1/4" phone type)
Accessories
Owner's Manual, Speaker Connection Cable, Connection Manual
Dimensions

Size and Weight ( Main Unit )
Width 456 mm 18 inches

Depth 343 mm 13-9/16 inches

Height 297 mm 11-3/4 inches

Weight 11.5 kg 25 lbs. 6 oz.

Size and Weight ( Subwoofer Unit )
Width 456 mm 18 inches

Depth 325 mm 12-13/16 inches

Height 560 mm 22-1/16 inches

Weight 11.5 kg 25 lbs. 6 oz.

* 0 dBu = 0.775 Vrms

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#1874296 - 01/16/08 07:28 PM Re: The Stereo Keyboard Amp Thread [Re: Kayvon]
Kayvon Offline
Gold Member

Registered: 05/03/05
Posts: 566
Loc: London
Motion Sound

MS-360-1

For use in a small room, as in a home or
live venue. Also, the 360-1 is ideal for
improving the sound of any digital piano
or an acoustic piano with a player system
that has CD/DVD or self-contained voices.
Great for use in a recording studio.

•AMPLIFICATION
100 watts (combined left and right
amplifiers and subwoofer amplifier)
• INPUTS
Two stereo pairs of ¼-inch with Volume, 3D
Expander, Bass, Mid, and Treble controls
One ¼-inch and XLR mic input
with Mic volume control
•OUTPUTS
XLR left and right outputs
•SPEAKERS
Two 8-inch speakers
Two 3.5-inch ferro-cooled horns
One 12-inch subwoofer
•DIMENSIONS & WEIGHT
24.5”H 20”W 17”D 70 lbs

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#1874297 - 01/16/08 07:28 PM Re: The Stereo Keyboard Amp Thread [Re: Kayvon]
Kayvon Offline
Gold Member

Registered: 05/03/05
Posts: 566
Loc: London
Motion Sound

MS-360-2

For use in larger rooms or live venues such as nightclubs
or houses of worship, that seat about 300 people.
Connect your other keyboards into the other channels
and have all of your sound under your control. Then,
connect to a house sound system via the two XLR’s outs.

•AMPLIFICATION
200 watts (combined left and right
amplifiers and subwoofer amplifier)
•INPUTS
Channel One: one stereo pair of ¼-inch inputs
MSDV (5pin DIN) input and output, with Volume,
3D Expander, Bass, Mid, and Treble controls
*Channel Two: two stereo pairs of ¼ inch inputs with
Volume, 3D Expander, Bass, Mid, and Treble controls
*MSDV (5pin DIN) accommodates
remote power ON/OFF and stereo signals
from such-equipped keyboards
•OUTPUTS
XLR left and right outputs
•CONTORLS
Master Volume control
*1/4-inch Click Track Monitor with Volume control
XLR mic input
SPEAKER
Two 12-inch speakers
Two 3.5-inch ferro-cooled horns
One 15-inch subwoofer
•DIMENSIONS
34.5”H 27.5”W 20”D 125 lbs

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#1874298 - 01/16/08 07:29 PM Re: The Stereo Keyboard Amp Thread [Re: Kayvon]
Kayvon Offline
Gold Member

Registered: 05/03/05
Posts: 566
Loc: London
Motion Sound

MS-360-5

Our highest powered
MS-360 is for the
environments where you
really need extra power.

•AMPLIFICATION
500 watts (combined
left and right
amplifiers and sub
woofer amplifier)
•INPUTS
Channel One: one stereo pair of ¼-inch inputs
MSDV (5pin DIN) input and output, with Volume, 3D
Expander, Bass, Mid, and Treble controls
Channel Two: two stereo pairs of ¼-inch inputs with
Volume, 3D Expander, Bass, Mid, and Treble controls
*Subwoofer: 00-100 Hz high frequency cut control
60 Hz 12 db boost cut control
45 hz 12 db boost cut control
MSDV (5pin DIN) accommodates remote power ON/
OFF and stereo signals from such-equipped keyboards
•OUTPUTS
XLR left and right outputs
•CONTROLS
Master Volume control
1/4-inch Click Track Monitor with Volume control
XLR mic input
•SPEAKER
Two 12-inch speakers
*Four 3.5-inch ferro-cooled horns
*One 18-inch NEO subwoofer
•DIMENSIONS & WEIGHT
34.5”H 27.5”W 20”D 140 lbs

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#1874299 - 01/16/08 07:32 PM Re: The Stereo Keyboard Amp Thread [Re: Kayvon]
Kayvon Offline
Gold Member

Registered: 05/03/05
Posts: 566
Loc: London
Reserved

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#1874337 - 01/16/08 10:08 PM Re: The Stereo Keyboard Amp Thread [Re: Kayvon]
Keyrick Offline
Senior Member

Registered: 12/07/03
Posts: 106
Loc: So. Cal / Orange County
I love Roland specs.
"Rated output 350 watts" "Power Consumption 94 Watts"
It's magic, I tell ya!

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#1874352 - 01/17/08 12:41 AM Re: The Stereo Keyboard Amp Thread [Re: Keyrick]
MurMan Offline
Senior Member

Registered: 11/17/03
Posts: 370
Loc: San Diego
I just finished reading the Owner's Manual on the Roland SA-1000. Some observations:

- The top section is stereo, but the separation must be minimal or non-existant on a cabinet that's 18" wide. I can't see how this is going to be useful for reducing stereo phasing problems.

- The sub-woofer connects using a special cable with 1/4" plugs. With 200W to the sub, it should take about ten bars to fry an instrument cable.

- The organ "Enhancer" switch is going to be pretty useless in a live situation.

- No wheels. This is one of the better features of the KC-500/550 amps.

- Looks like they focused on the player that needs to run a mic and a keyboard simultaneously.

- The high-res photos on the Roland site show what looks like fake wood trim panels. Like something from a 60's Chrysler. Maybe it too will fall off quickly.

I hate to be so negative, but I just don't see much on paper that gets me excited about this as a keyboard amp. The obvious unknown is how does it sound.


Edited by MurMan (01/17/08 12:43 AM)

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#1874408 - 01/17/08 05:38 AM Re: The Stereo Keyboard Amp Thread [Re: MurMan]
VLH Offline
Gold Member

Registered: 08/10/06
Posts: 601
I've been curious about the Roland SA-1000. I can agree in theory with your critique about the stereo separation. However,I disagree with you on the portability issue re: the lack of wheels being a flaw. One of the appealing things about the design of the SA-1000 is that it is two separate cabinets, each only 25 lbs. Wheels would actually be a problem in this case, since you would move either by carrying one in each hand or by putting it all on a hand truck. In fact, this split system gives the SA-1000 superior portabilty (compared to its near competitors, the Motion Sound 200 and the Traynor K4). One could even use only the top half for very small gigs, rehearsals, or leave the subwoofer in the car and only bring in the top half for home practice. This modular thinking is really clever design--provided it works well and sounds good, which is, of course, the starting point. As with all amps, you have to hear it--and I haven't yet, though I've been trying to find one to listen to.

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#1874628 - 01/17/08 11:13 AM Re: The Stereo Keyboard Amp Thread [Re: VLH]
MurMan Offline
Senior Member

Registered: 11/17/03
Posts: 370
Loc: San Diego
VLH,
I don't disagree with you on the portability issue. I go back and forth on whether it's easier to move my KC-500 or two EON10's. The rectangular shape of the SA-1000 would definitely be more stable on a cart.

Can we get a first-hand report on how this thing sounds?

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#1874641 - 01/17/08 11:33 AM Re: The Stereo Keyboard Amp Thread [Re: MurMan]
VLH Offline
Gold Member

Registered: 08/10/06
Posts: 601
I was out at my local GC two days ago--they didn't even know what it was. I am only finding it on European web sites. It's the first major manufacturer combo amp that's piqued my interest in some time. I had tried their KC-500 and didn't care for it, and have gone with two used GK keyboard amps, no longer made.

I expect it may have some of the same problems you hear about w/regards to the Traynor K4--which has a similar configuration but all in one cabinet. People have said that there is not enough separation and phase problems due to summing to mono on the subwoofer. My ears are not as well-trained in these comparisons and I'd definitely like to hear what some people who've had lots of gear think of this unit.

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#1875227 - 01/18/08 08:41 AM Re: The Stereo Keyboard Amp Thread [Re: VLH]
MurMan Offline
Senior Member

Registered: 11/17/03
Posts: 370
Loc: San Diego
After hating piano sounds through the KC-500 for years and reading what other guys on the forum use, I decided to go with pro audio stage monitors. Found a set of lightly used EON10 G2's a few weeks ago and the difference is incredible.

Keep in mind that I'm using them for stage volume and am not trying to drive the house.

I don't think that running a mono subwoofer causes phase problems. It's the summing of the mid and high frequencies caused by either the lack of speaker separation or by mixing the signals before the amp.

If you search the forum for Traynor, you'll find some opinions.

Good luck.


Edited by MurMan (01/18/08 08:48 AM)
Edit Reason: old age

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#1875234 - 01/18/08 08:48 AM Re: The Stereo Keyboard Amp Thread [Re: MurMan]
VLH Offline
Gold Member

Registered: 08/10/06
Posts: 601
Ooops--I meant "what others with more gear and better ears think about the Roland SA-1000." I've read what everyone has said about stereo stuff to date, including the Traynor.

I am also curious to learn if the new Groove Tubes is any better, after the miserable reviews the two previous editions got.


Edited by VLH (01/18/08 08:49 AM)

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#1875335 - 01/18/08 11:01 AM Re: The Stereo Keyboard Amp Thread [Re: VLH]
Kayvon Offline
Gold Member

Registered: 05/03/05
Posts: 566
Loc: London
 Originally Posted By: VLH
I expect it may have some of the same problems you hear about w/regards to the Traynor K4--which has a similar configuration but all in one cabinet. People have said that there is not enough separation and phase problems due to summing to mono on the subwoofer.


Doesn't the Traynor just have two separate speakers next to each other with no special processing though? I remember reading about the SA-300 having DSP Stereo enhancement of some description. Whether that's just two speakers next to each other with a simple stereo width enhancer or something cleverer I don't know.

One thing I think that is important to bear in mind when trying to reproduce acoustic piano is that in most cases you have an uneven stereo file playing ie there is more bass to your left and more treble frequencies to your right. I think this is the case on all the modern ROMpler piano patches i've played. This type of recording may not work as well with certain stereo enhancements that are more indiscriminate with the placement of the left & right channels. Certainly this was the case for the Groove Tubes SFX-100 I had for a while. However, chorus, reverb and leslie effects seemed to work well as I recall

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#1875415 - 01/18/08 12:57 PM Re: The Stereo Keyboard Amp Thread [Re: Kayvon]
Jazz+ Offline
MP Hall of Fame Member

Registered: 05/15/04
Posts: 4706

"If the speakers are too far apart, or not toed-in enough, the center-fill will be weak and "phasey," and the intermediate center-left and center-right localizations will tend to jump towards the speaker. If the speakers are too close together, or toed-in excessively, the stereo image will compress, lose its natural quality of airiness, and off-axis images will disappear."
_________________________
Roland FP-4 digital piano, 2 EV SXa-360 powered speakers (36 lbs each). WS-550 stand. Mason & Hamlin acoustic piano.

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#1875654 - 01/18/08 07:37 PM Re: The Stereo Keyboard Amp Thread [Re: Jazz+]
xmlguy Offline
Senior Member

Registered: 12/29/07
Posts: 274
Powered speakers and keyboard amps often share one common problem: gain controls nowhere near the keyboard.

I have mixer/amp for my own private monitor mix to passive monitors and to feed the main PA. I want all of the gain controls and displays to be an armslength away, not on the back of some speaker or a tall amp stack. I want my monitors to my right and left, pointed towards my ears, and I'll let the main PA can handle the audience. I can also shut down my monitor mix to do pan left&rights to confirm that I'm getting stereo to the main PA. I can also use the mixer to split my mic to separate keyboards for different vocal effects processing, totally under my control. The main PA only gets what I choose to send. Can't do that with a keyboard amp alone.

I've found that two unpowered speakers and a powered mixer are usually cheaper than two powered speakers or a combo amp, at least at the entry prices for comparable setups.

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#1875904 - 01/19/08 10:58 AM Re: The Stereo Keyboard Amp Thread [Re: xmlguy]
learjeff Offline
MP Hall of Fame Member

Registered: 08/09/04
Posts: 7694
Loc: NC, USA
Moronic manufacturers that publish WATTS for combined power+speaker units, rather than SPL values. Or perhaps, moronic customers who buy shit with meaningless specs?

ACK!

MORONS!
_________________________
Learjeff.net

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#1876026 - 01/19/08 05:08 PM Re: The Stereo Keyboard Amp Thread [Re: learjeff]
Bill H. Offline
MP Hall of Fame Member

Registered: 05/24/04
Posts: 3303
Loc: Columbia River Gorge, US
I know that I'm kind of off the subject of this thread, but I'm into the last part of a three night weekend with my Bose 802s that I picked up cheap off cl a few weeks ago, and they just blow me away so I'm talkin' \:D

But seriously, they're the only cabs I've used that sound the same from my position as out in the room. And that's a full sound that's kind of on the mellow side with a lot of stereo separation. The stereo imaging from where I'm at is astounding compared to any horn loaded boxes I've used, and I can hear both cabs very well even if one is somewhat further away. They really throw the sound around... the speakers are aimed in four different angles.

I'm still carrying too much stuff around, but I could see one gigging with these, a powered mixer with graphic EQ, and have an easier time moving that just about anything else out there. When I put them on my bathroom scales they came out at 28# each. I can easily carry them both. They're really small. Both of them together take up only half of the back seat of my Hyundai Elantra.

I'm at low to moderate volumes these days guys. Probably not a good choice for high SPL apps. But if you are like me and if a pair come up used...man... audition them and see what you think. They are my solution.

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#1876083 - 01/19/08 07:56 PM Re: The Stereo Keyboard Amp Thread [Re: Bill H.]
matted stump Online   content
10k Club

Registered: 10/26/03
Posts: 11739
I gigged a 4 piece jazz band for 7 years through a pair of Bose. Put them on speaker stands and be sure to use the EQ that comes with them.
_________________________
Moe
---
About the only thing I'd run through a Roland KC amp is a chainsaw.
http://www.hotrodmotm.com

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#1876321 - 01/20/08 11:03 AM Re: The Stereo Keyboard Amp Thread [Re: matted stump]
VLH Offline
Gold Member

Registered: 08/10/06
Posts: 601
Bill H, How do you get stereo with one powered mixer? My understanding is you need two separate amps or one stereo amp (which some how powers separately each channel. With a powered mixer, putting the L/R out into channel 1 and the R out into channel two and sending them to the speakers will still sum the stereo back to mono.

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#1876326 - 01/20/08 11:10 AM Re: The Stereo Keyboard Amp Thread [Re: VLH]
matted stump Online   content
10k Club

Registered: 10/26/03
Posts: 11739
Many powered mixers have stereo amps. Most of them do these days in fact.
_________________________
Moe
---
About the only thing I'd run through a Roland KC amp is a chainsaw.
http://www.hotrodmotm.com

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#1877136 - 01/21/08 05:36 PM Re: The Stereo Keyboard Amp Thread [Re: matted stump]
nmcq Offline
Senior Member

Registered: 11/05/02
Posts: 283
I was at the Motion Sound booth but somehow missed this one. It's a new big brother to the KP200S:

KP-500SN Stereo Keyboard Combo Amp

The new KP-500SN 500-watt stereo combo amp is designed specially for the new stereo keyboards available today. Even though it has increased power, its portability has been improved through the use of light-weight neodymium speakers. The KP-500SN's 500-watt capability is designed to handle large live venues and its angled cabinet projects and dramatically widens the stereo keyboard sound, which can be enhanced further utilizing our proprietary 3D expander control. This takes the stereo sound and turns it into real 3D imagery far beyond the sound delivered through typical flat-front, forward-facing mono and stereo enclosures, creating an incredible sonic experience for audiences in large rooms and live venues.
Specs
500 watts (250 watts per channel)
Two stereo preamps with Volume, 3D Expander, Bass, Mid, and Treble controls
Two pairs of 1/4-inch inputs on each channel
Master Volume control
1/4-inch Click Track Monitor with Volume control
XLR mic input
XLR left and right outputs
1/4-inch subwoofer output
DIN slave amp output
Two 12-inch neodymium speakers
Four 3.5-inch ferro-cooled horns
18.75"H 24.5"W 16.75"D 57 lbs

Neil
_________________________
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#1877152 - 01/21/08 06:20 PM Re: The Stereo Keyboard Amp Thread [Re: nmcq]
Dave Ferris Offline
MP Hall of Fame Member

Registered: 03/05/07
Posts: 4388
Loc: Glendale, Ca.
That's funny...I was there too and missed it. They had a FP4 hooked up to that new MS-360 living room piece and what appeared to be a KP200 next to it. The description says 4 (?) horns, the 12's should help the low end and harsh/brittle qualities of that amp.
57 lbs. is a bruiser though.
_________________________
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2005 NY Steinway D, Yamaha CP4, CP5, RCF TT08A, TT22A speakers


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#1877192 - 01/21/08 07:50 PM Re: The Stereo Keyboard Amp Thread [Re: Dave Ferris]
matted stump Online   content
10k Club

Registered: 10/26/03
Posts: 11739
_________________________
Moe
---
About the only thing I'd run through a Roland KC amp is a chainsaw.
http://www.hotrodmotm.com

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#1877196 - 01/21/08 08:05 PM Re: The Stereo Keyboard Amp Thread [Re: matted stump]
matted stump Online   content
10k Club

Registered: 10/26/03
Posts: 11739
Looks pretty cool actually. Only 2 lbs heavier than the MS KP-200, almost the same size, but more than twice the power, and 12"s instead of 10"s.
_________________________
Moe
---
About the only thing I'd run through a Roland KC amp is a chainsaw.
http://www.hotrodmotm.com

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#1877234 - 01/21/08 10:01 PM Re: The Stereo Keyboard Amp Thread [Re: matted stump]
Dave Ferris Offline
MP Hall of Fame Member

Registered: 03/05/07
Posts: 4388
Loc: Glendale, Ca.
The 200 is 55 lbs. ?...Hmmm, maybe all that time at the gym is paying off...doesn't feel that heavy.

Maybe that was the 500 sitting there next to fancy lamp table that resembled the MS-360.
_________________________
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2005 NY Steinway D, Yamaha CP4, CP5, RCF TT08A, TT22A speakers


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#1877389 - 01/22/08 09:18 AM Re: The Stereo Keyboard Amp Thread [Re: matted stump]
nmcq Offline
Senior Member

Registered: 11/05/02
Posts: 283
 Originally Posted By: mate_stubb
Looks pretty cool actually. Only 2 lbs heavier than the MS KP-200, almost the same size, but more than twice the power, and 12"s instead of 10"s.


I found out about the KP500-SN only after getting home from NAMM and reading through some of the promo material. I asked a buddy going the next day to stop by and ask them about it. Word back (this is 2-level hearsay, now) is that they said it wasn't currently available, and might be expected March or April. I was very interested because I JUST bought a Slave for my KP200, and it's still within the return period. Looks like I'll be keeping it for now. I have an e-mail into the company, but understandably haven't heard back yet. Will be interesting to see if/how the "horns" change the sound from the KP200. Wonder what "SN" means; "Stereo New"? "Super Nasty"? "Sonic Normalizer"? ;-)

Neil
_________________________
myspace.com/AlteredDominant www.Prymary.com
NordElectro3/S90XS/SteinwayS(midi'd)/KX88/Apple MBP, iMac/MainStage2/Scrbee/NI Komplete/ApogeeDuet/QSCplx1804/JBLmrx512/SpcStnSRX/LogicPro9/DP/ProTools

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#1877642 - 01/22/08 03:32 PM Re: The Stereo Keyboard Amp Thread [Re: nmcq]
nmcq Offline
Senior Member

Registered: 11/05/02
Posts: 283
Just heard from John Fisher at Motion Sound on the KP500-SN:
"The KP-500SN will be available in May/June. It was a very big hit at NAMM! There are some issues to work out though such as which Neodymiun speakers to use and what class of power amplifier.

The SL-200S will plug into the KP-500S the same as your KP-200S and the feet will line up with the recesses."

Neil
_________________________
myspace.com/AlteredDominant www.Prymary.com
NordElectro3/S90XS/SteinwayS(midi'd)/KX88/Apple MBP, iMac/MainStage2/Scrbee/NI Komplete/ApogeeDuet/QSCplx1804/JBLmrx512/SpcStnSRX/LogicPro9/DP/ProTools

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#1877656 - 01/22/08 03:50 PM Re: The Stereo Keyboard Amp Thread [Re: nmcq]
matted stump Online   content
10k Club

Registered: 10/26/03
Posts: 11739
This could be a winner for the minimal rig crowd.
_________________________
Moe
---
About the only thing I'd run through a Roland KC amp is a chainsaw.
http://www.hotrodmotm.com

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#1877692 - 01/22/08 04:47 PM Re: The Stereo Keyboard Amp Thread [Re: nmcq]
VLH Offline
Gold Member

Registered: 08/10/06
Posts: 601
I haven't been at the gym. I sure don't want to heft 57 lbs.

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