Problem with a Yamaha DSP A1 (1 Viewer)

[Thira]

My Yamaha DSP A1 shuts off when the volume is slightly more than 1/4 max. Does anyone know why it does this?
I am new to home theater and recently built a media room, 22'x20'. The room was pre wired during construction. Along the front wall is a Panasonic 50' plasma TV. The components include:
Yamaha DSP A1
Sony Turntable
Samsung TS160 HDTV Tuner
Adcom ACE-315 Surge Supressor
Adcom GFA-555 Power Amp (for 4 speakers around pool- two Bose mounted under a Lanai & two rock speakers in the Garden, two other rooms each with two speakers)
CSI Speaker selector for the speakers running off the Adcom GFA-555
Harman/Kardon TU930 AM/FM Tuner with a Terk FM50 antenna in the attic (wish I had a solution for an AM antenna for reception of far away college football games)
Pioneer 563A-S DVD Player( I plan to replace with a Denon 5900)
The Yamaha DSP A1 drives
MonitorAudio Silver SLR center channel speaker
MonitorAudio Silver S10 x2
MonitorAudio Silver S1 x2
MonitorAudio SFX Surrounds x2
Velodyne HSG 18
I had never had this problem previously when the Yamaha was connected in another room with a much lower end 6 speakers (2 fronts, center, two rears and subwoofer).
Secondly if I were to replace the yamaha, what would one recommend to complement the components in my system? I am trying to better my knowledge of Home Theater and would like a quality system without getting totally out of control on the cost.
Thank you for the anticipated reply.

 

[DonnyD]

Just a couple of guesses here....
1) check the ohms of your speakers at the speaker wires at the receiver to see the REAL load per channel....this will confirm the load of the speakers and tell you if you're driving the wrong load for the Yam. Be sure to unhook the speaker wires from the receiver for this.
2) check continunity of each speaker wire too....this should tell you if you have a wiring problem somewhere or a blown voice coil.

The A1 is a great unit and I certainly wouldn't replace it, especially until you've got this problem resolved.

 

[Jeffrey Stanton]

I've got a DSP-A1. Have never had that problem except ONCE. It turned out that the banana plugs to my right main Klipschorn's bass bin had come loose, and only at elevated volume the floor would shake enough to vibrate the ends of the wires together briefly and shut off the amp (protection circuit).

I figured this out when I pulled the K-horn out of it's corner and found the banana plug leads laying side by side in CLOSE proximity to each other. I plugged them back in and it hasn't happened since.

I suspect you might have a short somewhere you are unaware of....

 

[Keith Mickunas]

Yamaha's flagship receivers typically have good amp sections. When did this start happening? Was it right after you made some changes? If so, I think that it's definitely a wiring problem.

However you mention 7 speakers, how do you have them wired up? Are 2 of those front effects? Or are you running some in parallel? If you have to many speakers connected to one jack that can really mess things up.

To test it, disconnect everything but the mains, and see if it works, then add the center, and so on. If it happens with a certain speaker, connect that speaker to a different output and see if it still shorts, that'll tell you if it's the amplifier or something in the speaker or cable.

 

[Wayne A. Pflughaupt]

I had never had this problem previously when the Yamaha was connected in another room with a much lower end 6 speakers...

Actually, Thira, price of the speakers is no indication as to how difficult a load they may be. In fact, higher-end speakers are often a more difficult load than cheap speakers.

For instance, your center channel and L/R mains are both 6-ohm speakers, and I expect that’s where your problem is (assuming it isn’t a short caused by loose strands of speaker wire).

I’m with Donny – the A1 is a great unit and I wouldn’t rush to replace it. Probably all you need to do is get an outboard amp for at least the mains, and the problem will most likely go away. You can do a test-run by temporarily powering your mains off the Adcom.

Regards,
Wayne A. Pflughaupt

 

[Thira]

Thank you so much for the input. I did finally find and fix the problem. I had added a media room addition to my home. The room was prewired and sheet rocked in during construction.
The electrician must have spliced the right front speaker. I disconnected all speakers but the mains. I added and tried speakers until I found the problem. WHen I added the fronts the system shut down whenever I increased volume. The right front +/- wires were correctly connected to the speaker and A/V unit. I reversed the +/- at the receiver and the problem was solved. It kinda of ticked me off, as I specified that the speaker wires were supposed to be single uninterrupted wiring. All I can figure is that the electrician either ran out of wire and screwed up a splice which is now hidden behind sheet rock walls. I caught the electrician once in his truck getting high, so maybe he liked the color combo.
But thanks again. My system sounds great now.
BTW, I do have an adcom 555 power amp driving four speakers around my pool and speakers in my dining room.
I do find that the DSP A1 more than adequately drives my system. In fact the system sounds great!

 

[SP01L3R]

Hi everyone. After being using my DSP A1 for 14 years, living in 3 different countries, I've just moved to a new house and assembled my system all together: YAMAHA DSP A-1 BOSE ACOUSTIMAS 12 SUB WOOFER PSB SubZero SATELLITE TUNER PIONEER DVR650H WD LIVE MEDIA PLAYER After watching a couple of movies, today on the middle of watching a movie, my YAMAHA DSP A1 simply shuts down. I've read the impedance issue... but... even when I disconnect absolutely every single plug, the amplifier shuts down automatically after a while. Then, I tried to reconnect one-by-one the BOSE. It happens that after a while it stays ON and plays the sound ONLY without EFFECTS. If I do a TEST the CENTER and SORROUND SPEAKERS do no play. I've tested individually each set of speakers they seem fine. I have decided to open the cover, nothing unusual there. The only thing I have my doubts is the FAN. Does anyone knows if this FAN works all the time, or just works when needed? On power-up the FAN spins just a little and I haven't seen it spinning at all after 20 minutes... Everytime I try to connect, either shuts down after 3 seconds, or stays on but without EFFECTS (plain Left & Right channels only) If I press EFFECT OFF, it plays L + R (sometimes C)... My living room is air conditioned as well... Does anyone have any clues? I really would be very disappointed if I have to substitute my unit for a more modern one. The problem is, I live in Qatar and so far, after few e-mails and tries to contact the agent, have been unsuccessful. Regards

 

[Leo Kerr]

Carlos, it's not quite clear to me, but... ...you can get some (but not all) speakers to work? ...if you plug one speaker at a time in -- for example, front-left, into front left, and it works. Unplug, and then connect front-right to Front-left. unplug, and then put the center into front-left. Individually check all speakers against a known working amp channel. If that all works, then repeat the process, taking a known working speaker, and move through all of the amp-outputs. This should tell you if you've got a bad speaker that's freaking the amplifier out, or if you've got an amplifier circuit going bad. Alternatively, you might also have a power supply going bad, if it's something you can run, say, any two speakers forever, but when you add a third, or something like that. I'd guess it might be a capacitor. I'm not looking forward to the idea that my own 14 year old DSP-A1 might be approaching end-of-life, either. Although it's hard to believe -- 14 years! Leo