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Gear / Technical Help => Playback Forum => Topic started by: Massive Dynamic on January 19, 2025, 05:14:50 PM

Title: Integrated amp: repair or replace
Post by: Massive Dynamic on January 19, 2025, 05:14:50 PM
I’ve got an inexpensive Class D amp in my system taking the place of a nicer Class A amp that developed a hum. A job layoff delayed sending it in for repair, and now the amp is at least 20 years old.

If I replace that Class A amp, here’s what I need:
-must drive 4-ohm speakers
-dedicated sub-out or pre-outs
-4+ inputs

Amps from NAD or Arcam might do, but I’m open to recommendations for gear I’ve not found in my initial searches. Budget is ~$700, which is a bit more than the anticipated amp repair costs.
Title: Re: Integrated amp: repair or replace
Post by: grawk on January 19, 2025, 05:43:59 PM
Which class D amp? I prefer my ice power based diy class d amp to my old hafler and marantz class a amps.
Title: Re: Integrated amp: repair or replace
Post by: Massive Dynamic on January 19, 2025, 06:29:11 PM
Which class D amp?

A Panasonic XR-25 that I paid a little over $100 for. It's ok, but it doesn't sound as good as the Primare. And the sub out quit working.
Title: Re: Integrated amp: repair or replace
Post by: grawk on January 20, 2025, 07:10:37 AM
https://www.ebay.com/itm/396131602569?_skw=icepower&itmmeta=01JJ1STF2H7HNTZYTA46VGT5KQ&hash=item5c3b489089:g:sGwAAOSwfRxniui-&itmprp=enc%3AAQAJAAAA4HoV3kP08IDx%2BKZ9MfhVJKkr%2BCjtgc4uy%2FwHDp%2FXwfkCL8bOaEuP%2FcRIaeLd8nXpLMRAaYGBd8WPQzbSGrYkMLu2WD3a47qI01bgARix6qT8PbMlgLk%2BZ%2B36VISL%2FpqWLzLONUFgCWxqiD5Pp90lAGmHfG9ObXDQeZlQ5128R%2Bf0%2FD9m6CT8nHgyGbI6C0xPgxZ2olthYBdK1yx4idxnCLX%2FNXi6rnCnkjaFf7PeFMJ4gnegkF9y6hQ2iuX2v%2FmPi1BnYT%2BqKNOJfuHWjbe%2F%2BnLdDg6xlvAxt0HtBQR645SC%7Ctkp%3ABk9SR8Tx6bmQZQ
Title: Re: Integrated amp: repair or replace
Post by: Gutbucket on January 20, 2025, 09:57:05 AM
I used a couple panasonic xr55s for years, the slightly later bigger brother of the xr25.  They sounded very good and were flexible enough for my needs. I especially liked their very transparent and particularly useful tone controls. Biggest problem was that the internal power supplies were a bit undersized. They weren't current monsters, but otherwise decent early class D. 
Title: Re: Integrated amp: repair or replace
Post by: Massive Dynamic on January 20, 2025, 06:54:27 PM
Auction item (https://www.ebay.com/itm/396131602569?_skw=icepower&itmmeta=01JJ1STF2H7HNTZYTA46VGT5KQ&hash=item5c3b489089:g:sGwAAOSwfRxniui-&itmprp=enc%3AAQAJAAAA4HoV3kP08IDx%2BKZ9MfhVJKkr%2BCjtgc4uy%2FwHDp%2FXwfkCL8bOaEuP%2FcRIaeLd8nXpLMRAaYGBd8WPQzbSGrYkMLu2WD3a47qI01bgARix6qT8PbMlgLk%2BZ%2B36VISL%2FpqWLzLONUFgCWxqiD5Pp90lAGmHfG9ObXDQeZlQ5128R%2Bf0%2FD9m6CT8nHgyGbI6C0xPgxZ2olthYBdK1yx4idxnCLX%2FNXi6rnCnkjaFf7PeFMJ4gnegkF9y6hQ2iuX2v%2FmPi1BnYT%2BqKNOJfuHWjbe%2F%2BnLdDg6xlvAxt0HtBQR645SC%7Ctkp%3ABk9SR8Tx6bmQZQ)

How do you manage multiple inputs into this amp?
Title: Re: Integrated amp: repair or replace
Post by: Gutbucket on January 20, 2025, 07:02:01 PM
I don't mean to speak for grawk, but the item linked is a two channel stereo amplifier only, with no input switching, no volume control, no anything else, just good amplification to drive a pair of speakers.  You'd need a preamp with source switching and presumably volume control as well between that and whatever the source components are.
Title: Re: Integrated amp: repair or replace
Post by: grawk on January 20, 2025, 07:44:56 PM
I don't mean to speak for grawk, but the item linked is a two channel stereo amplifier only, with no input switching, no volume control, no anything else, just good amplification to drive a pair of speakers.  You'd need a preamp with source switching and presumably volume control as well between that and whatever the source components are.

Yup.
Title: Re: Integrated amp: repair or replace
Post by: Massive Dynamic on January 21, 2025, 10:56:23 PM
I don't mean to speak for grawk, but the item linked is a two channel stereo amplifier only, with no input switching, no volume control, no anything else, just good amplification to drive a pair of speakers.  You'd need a preamp with source switching and presumably volume control as well between that and whatever the source components are.

Yup.
That's what I inferred, but I don't think I'm interested in a DIY solution. I'm starting to learn toward getting my amp repaired.

I did a forum search, but did not see any reference regarding George Meyer AV (https://www.georgemeyer-av.com/) in LA which is the authorized service center for Primare. I do see they have used equipment for sale, too.
Title: Re: Integrated amp: repair or replace
Post by: grawk on January 22, 2025, 06:04:53 AM
That’s not diy, it’s a built amp. But it does require a preamp.
Title: Re: Integrated amp: repair or replace
Post by: heathen on February 27, 2025, 02:48:17 PM
Yamaha A-S801 fits the bill.  I love mine, and the loudness feature is awesome.
Title: Re: Integrated amp: repair or replace
Post by: Massive Dynamic on June 10, 2025, 11:05:10 PM
Yamaha A-S801 fits the bill.  I love mine, and the loudness feature is awesome.

Thanks for the heads up. I think the watts/features/price of the A-S501 might be perfect for my system and size of room.
Title: Re: Integrated amp: repair or replace
Post by: Massive Dynamic on June 16, 2025, 10:38:48 PM
Yamaha A-S801 fits the bill.  I love mine, and the loudness feature is awesome.

Thanks for the heads up. I think the watts/features/price of the A-S501 might be perfect for my system and size of room.

Looking over the manual, it looks like the sub out frequency cut-off is 100 Hz. My sub only outputs up to 90 Hz. Is that 10 Hz gap going to be noticeable? Can't say that spec thrills me.
Title: Re: Integrated amp: repair or replace
Post by: goodcooker on June 17, 2025, 10:38:03 AM

I think you may be looking at this backwards. The 100hz point is where the slope of the low pass filter begins to attenuate. So, on a graph, if looking at the low frequencies it will be a straight line from 20 - 100 hz then the attenuation slope begins to drop. You should get full range to your sub.

20hz       40hz      60hz     80hz     100hz
_|________|_______|______|______|
                                                  |      \
                                                  |        \------LPF 12/18dB/octave (typical)
                                                90hz      \
                                                               \
Title: Re: Integrated amp: repair or replace
Post by: Massive Dynamic on June 17, 2025, 09:51:36 PM

I think you may be looking at this backwards. The 100hz point is where the slope of the low pass filter begins to attenuate. So, on a graph, if looking at the low frequencies it will be a straight line from 20 - 100 hz then the attenuation slope begins to drop. You should get full range to your sub.

20hz       40hz      60hz     80hz     100hz
_|________|_______|______|______|
                                                  |      \
                                                  |        \------LPF 12/18dB/octave (typical)
                                                90hz      \
                                                               \
So, full frequencies thru the speaker outs, but only 100Hz and lower thru the sub out? That'll work. I thought there might be a strict crossover inside the unit that split the frequencies between outputs.
Title: Re: Integrated amp: repair or replace
Post by: heathen on June 18, 2025, 07:08:09 AM
So, full frequencies thru the speaker outs, but only 100Hz and lower thru the sub out?

I believe that is the case.  I think it's sending full range through the speaker jacks all the time, while simultaneously sending a low-passed signal through the sub out.  So, you'll never have the 10 Hz "gap" in the signal sent to your speakers.

Also, if/when you get it, make sure to read the manual about the loudness control.  Used properly it's amazing...I wish more modern high end amps would have it.