Hi
I wonder if you may be able to help?
I have run my Adcom 24/7 for the past 3 years, generally on back ground music which used to be pre amp volume setting of around 8 - 12ish and every now and then turn it up 🙂 to pre amp volume of around 20 - 30ish ( you had to raise you voice to be heard) did not need it any louder than 40 as things would start to shake or vibrate in the house.
However over the last few years I have gradually but noticeably been upping the pre amp volume, just now I was turning it up from 25 (background) volume to 90 and it was not exactly loud at 90 pre amp volume!! 90is the loudest the pre amp has ever been when plugged in to the Adcom.
I changed out the pre amp about 18months ago so I am assuming its the Adcom
Any thoughts as to what may need checking?
Oh! the sound quality remains Good 🙂 from low to higher volumes, which surprises me as I would have thought if something was wrong the sound quality would go..?
Please keep any suggestions basic ;-) as I am a beginner with electronics.
Many many Thanks for any thoughts.
Cheers
Mark
I wonder if you may be able to help?
I have run my Adcom 24/7 for the past 3 years, generally on back ground music which used to be pre amp volume setting of around 8 - 12ish and every now and then turn it up 🙂 to pre amp volume of around 20 - 30ish ( you had to raise you voice to be heard) did not need it any louder than 40 as things would start to shake or vibrate in the house.
However over the last few years I have gradually but noticeably been upping the pre amp volume, just now I was turning it up from 25 (background) volume to 90 and it was not exactly loud at 90 pre amp volume!! 90is the loudest the pre amp has ever been when plugged in to the Adcom.
I changed out the pre amp about 18months ago so I am assuming its the Adcom
Any thoughts as to what may need checking?
Oh! the sound quality remains Good 🙂 from low to higher volumes, which surprises me as I would have thought if something was wrong the sound quality would go..?
Please keep any suggestions basic ;-) as I am a beginner with electronics.
Many many Thanks for any thoughts.
Cheers
Mark
Last edited:
Hi Mark,
Consumer electronics are not designed to run all the time. What you need is a Bogen amplifier designed for PA use in permanent installations. Those will run 30 years all the time.
First impression ... there are capacitors in the feedback loop to ground that may have opened. This would cause exactly what you are describing. Okay, now to service your amplifier, take it to a real, honest experienced audio technician. He (or she) will have proper equipment including distortion analyzers, a stock of real parts and probably won't fix TVs and monitors.
If you take your amplifier to anyone less, it may cost you more, and even end up with destroyed equipment. Your Adcom is well worth repair (I was authorized warranty for these) and due some respect from the service engineer.
You can continue to use this amplifier as you were, but it is not what it was designed to do. Bogen is a very good brand of PA equipment and will last with decent sound quality. They are mono amplifiers and cost more than the other stuff. You want the HTA series (not TPU as they are lower fidelity). I generally use HTA-250 amplifiers in paging installations, but that is 250 watts designed to run all the time. They are going to be larger and heavier than the Adcom. So for you, HTA-125A, 125 watts. You need two for stereo. They will run 8 ohm loads. maybe 4 (look them up), but a 70 volt line will run many, many speakers (each with a 70 volt line step down transformer). This is the normal way to run background music distributed over a large area.
Hope that helps somewhat, Chris
Consumer electronics are not designed to run all the time. What you need is a Bogen amplifier designed for PA use in permanent installations. Those will run 30 years all the time.
First impression ... there are capacitors in the feedback loop to ground that may have opened. This would cause exactly what you are describing. Okay, now to service your amplifier, take it to a real, honest experienced audio technician. He (or she) will have proper equipment including distortion analyzers, a stock of real parts and probably won't fix TVs and monitors.
If you take your amplifier to anyone less, it may cost you more, and even end up with destroyed equipment. Your Adcom is well worth repair (I was authorized warranty for these) and due some respect from the service engineer.
You can continue to use this amplifier as you were, but it is not what it was designed to do. Bogen is a very good brand of PA equipment and will last with decent sound quality. They are mono amplifiers and cost more than the other stuff. You want the HTA series (not TPU as they are lower fidelity). I generally use HTA-250 amplifiers in paging installations, but that is 250 watts designed to run all the time. They are going to be larger and heavier than the Adcom. So for you, HTA-125A, 125 watts. You need two for stereo. They will run 8 ohm loads. maybe 4 (look them up), but a 70 volt line will run many, many speakers (each with a 70 volt line step down transformer). This is the normal way to run background music distributed over a large area.
Hope that helps somewhat, Chris
Hi Chris,
Thanks for the informative reply!
Yes I know what you mean about an honest experienced audio technician, I scoured the local area for one a while back, to repair a pre amp/dac that sounded absolutely wonderful with the 545. The search was not very fruitful, either low quality parts & no understanding of decent parts, not interested in matching stereo sides, not scoped up and best guess work... or, so expensive I may as well just buy a new amp.... umm yes I ended up driving for 3 hrs! to find a decent honest experienced repair guy, but not sure if he is around anymore :-(
So, bearing that in mind I think I would prefer to attempt a little soldering my self, as I would treat my amp with kindness and as much care as I am able to give, as I like it!! and want it to work for many years to come!! ;-)
Hmm so if I took some pictures might you be able to point out which caps are the feedback to ground ones...??
...or I may be able to spot them if they have bulged...
Yes I don't want to kill the 545 by running it 24/7, but it is nice to have it on! so when ever awake there is music. I think one of the reasons for leaving it on was to save on the wizz pop bang whistle discharge noise through the speakers...
I may have a little look at the Bogens like you suggest
but I do like the sound of the 545.
Yes very helpful, Thank you!
Thanks for the informative reply!
Yes I know what you mean about an honest experienced audio technician, I scoured the local area for one a while back, to repair a pre amp/dac that sounded absolutely wonderful with the 545. The search was not very fruitful, either low quality parts & no understanding of decent parts, not interested in matching stereo sides, not scoped up and best guess work... or, so expensive I may as well just buy a new amp.... umm yes I ended up driving for 3 hrs! to find a decent honest experienced repair guy, but not sure if he is around anymore :-(
So, bearing that in mind I think I would prefer to attempt a little soldering my self, as I would treat my amp with kindness and as much care as I am able to give, as I like it!! and want it to work for many years to come!! ;-)
Hmm so if I took some pictures might you be able to point out which caps are the feedback to ground ones...??
...or I may be able to spot them if they have bulged...
Yes I don't want to kill the 545 by running it 24/7, but it is nice to have it on! so when ever awake there is music. I think one of the reasons for leaving it on was to save on the wizz pop bang whistle discharge noise through the speakers...
I may have a little look at the Bogens like you suggest
but I do like the sound of the 545.Yes very helpful, Thank you!