Berkel Posted October 16, 2019 Share Posted October 16, 2019 Hi all ; I have a Rotel RA 971 Mk. II, which is quite good, but have been thinking about obtaining a better quality pre amp to run through it. Any advice would be welcome. I only listen to " Classical " music, including a lot of organ. Thanks. Link to comment Share on other sites More sharing options...
Ittaku Posted October 16, 2019 Share Posted October 16, 2019 A quick google suggests this device has pre out but not power in as an option. That means to use a separate preamp you'd be passing it through the external preamp first and then through the Rotel's own preamp. That is not going to lead to better sound. Link to comment Share on other sites More sharing options...
Berkel Posted October 17, 2019 Author Share Posted October 17, 2019 Thanks Con .... you're correct. I had the mistaken belief that it would take a " pre - in ". So you saved me from making a stuff up ! Dennis Link to comment Share on other sites More sharing options...
surprisetech Posted October 17, 2019 Share Posted October 17, 2019 Those Rotel integrateds are great designs, physically and electrically. Even if yours did have a 'main in' option I can't imagine you'd make any improvement by adding a separate pre and interconnect to the signal path. Unless you were chasing some 'signature sound' that a particular pre might offer (i.e. tubes). The built-in pre has only one gain stage, a high performance TI opamp. Tone control range is relatively subtle at +/-6dB and can be bypassed completely as you would know. Given the age of these beauties, I think your money would be better spent having someone who knows what they're doing, replace/upgrade the electrolytics in the signal path (there's only 3 in each channel) and in the power supply. And maybe apply a good contact cleaner to the switches and pots. The only issue I've ever come across with these amps is that the pre-amp design (and that of a number of products from that era) do not like the DC signals present when connecting a mobile phone to any of the line inputs. Phones put a small DC voltage on the headphone output lines to provide the control features available on phone headsets. This causes a thump when connecting/disconnecting the cable, or selecting/deselecting the input. It's only brief, and the amp handles it, but lower-powered speakers might suffer. I modified my RA-970BX and added a pair of nice big poly caps in series on the Aux2 input so that I had one input I could use with my phone. Link to comment Share on other sites More sharing options...
surprisetech Posted October 17, 2019 Share Posted October 17, 2019 17 minutes ago, surprisetech said: replace/upgrade the electrolytics in the signal path (there's only 3 in each channel) Sorry, there's a second opamp and another 2 electros in the signal path when the tone controls are engaged. Link to comment Share on other sites More sharing options...
Berkel Posted October 17, 2019 Author Share Posted October 17, 2019 Thanks for your reply and advice. The RA 971 Mk. II is a nice amp, much better than a Rotel I had some time ago, which was tinny and awful. I've taken it to my local electronics technician, because there was some static when moving the volume knob. However, he couldn't find any dirt on the pot. He gave it a clean and re - soldered some bits & pieces. His opinion was that it's a good amp. I just thought about an economical way to achieve better sound, but even as it stands, it's quite acceptable. Cheers, Dennis Link to comment Share on other sites More sharing options...
Berkel Posted October 17, 2019 Author Share Posted October 17, 2019 Do you think there would be a SIGNIFICANT improvement by going to separates, i.e. pre & power amps ? Probably Rotel, and used, as my budget is limited. Thanks, Dennis Link to comment Share on other sites More sharing options...
Ittaku Posted October 17, 2019 Share Posted October 17, 2019 There are no definites. Depends entirely on the components you end up choosing. You can get worse sounding separates than an integrated. 1 Link to comment Share on other sites More sharing options...
surprisetech Posted October 17, 2019 Share Posted October 17, 2019 16 hours ago, Berkel said: Do you think there would be a SIGNIFICANT improvement by going to separates, i.e. pre & power amps ? Probably Rotel, and used, as my budget is limited. Thanks, Dennis Where in particular do you feel an improvement is required? Depending on what improvements you're looking for, room treatment or tweaks/upgrades of other components might give better value. What source component/s and speakers make up the rest of the system? From the RA-870 onwards, the '70' series of integrateds has been a real sweet-spot for audiophile sound at a fair price. The only reason I can think of for moving to separates from what you already have, would be to provide more power, which might be necessary if you're driving very inefficient speakers and running out of power to do justice to those 16' organ pipes! Link to comment Share on other sites More sharing options...
Berkel Posted October 18, 2019 Author Share Posted October 18, 2019 Thanks for your interest. My speakers are B & W CM Link to comment Share on other sites More sharing options...
audiofeline Posted October 18, 2019 Share Posted October 18, 2019 Given the design of your amp, if you are wanting to move to separates it appears that it would be easier to get a power amp and use your integrated's preamp. However, the above posts suggest that your amp is very good quality and you are on a budge. Therefore, I would suggest you enjoy your amp for the present and save your money so you can buy a power amp which will be a substantial improvement over that section in your integrated (so you will be assured of having an actual upgrade), Then enjoy it and save your money until you can buy a quality preamp to match your power amp's quality. Link to comment Share on other sites More sharing options...
Berkel Posted October 18, 2019 Author Share Posted October 18, 2019 Thanks for the " sound " advice ( excuse the pun ). I was thinking along the same lines, if I can get a good quality power amp at a reasonable price. I only have a small - ish lounge room ( in a 3 BR villa unit ) and don't listen at very high levels. My speakers are B&W CM5 S2, which are beautiful and make music, rather than reproduce sound ( IMHO ). I like a big, laid back, open quality of sound, which is easy on the ears, as though sitting perhaps 2/3rds the way back in a large concert hall. The Rotel pretty much does this, but I would like to have just a bit more power on tap, similar to driving an 8 cylinder car .... don't have to push it to get results, if I may use this analogy. I listen to a lot of organ music, and my small REL sub woofer handles the lower notes fairly well. Cheers, Dennis 1 Link to comment Share on other sites More sharing options...
Ittaku Posted October 18, 2019 Share Posted October 18, 2019 This is the impedance plot of your speakers. While they do briefly dip below 4 ohms at higher frequencies it demonstrates they're probably not that hard to drive with an amp that can drive 6-8 ohms well. You probably don't need a high current amp and could even get away with a valve power amp if you wished to go in that direction. Knowing your budget would help in making recommendations for a power amp for you. Link to comment Share on other sites More sharing options...
Berkel Posted October 18, 2019 Author Share Posted October 18, 2019 Gosh, that looks too complicated for my simple brain ! Thanks for going to the effort of sending the graph. I absolutely love valve amps, and have had a few in the past, when I was working and had some money to spare. The downside ( for me ) is that they're heavy and take up a lot of space. As I'm now an age pensioner, my budget is pretty restricted, so I guess $1000 would be my limit. Any suggestions will be appreciated. Dennis Link to comment Share on other sites More sharing options...
Ittaku Posted October 18, 2019 Share Posted October 18, 2019 (edited) 25 minutes ago, Berkel said: I absolutely love valve amps, and have had a few in the past, when I was working and had some money to spare. The downside ( for me ) is that they're heavy and take up a lot of space. As I'm now an age pensioner, my budget is pretty restricted, so I guess $1000 would be my limit. Any suggestions will be appreciated. Okay that's a tricky price range for a standalone power amp. I'd suggest you have to go second hand to ensure you get something better than you currently have. Keep an eye out on the classifieds here as some great stuff comes up. We'll point anything out that we think might suit. Edited October 18, 2019 by Ittaku Link to comment Share on other sites More sharing options...
Berkel Posted October 18, 2019 Author Share Posted October 18, 2019 Thanks for the advice. Dennis Link to comment Share on other sites More sharing options...
Berkel Posted October 18, 2019 Author Share Posted October 18, 2019 I just saw an amp in the classifieds and wonder if it's any good : Plessis Audio S1 ..... ? Link to comment Share on other sites More sharing options...
Al.M Posted October 18, 2019 Share Posted October 18, 2019 (edited) Better quality used amps for around $400-800 like Musical Fidelity, Roksan and others would be better for the speakers. See regular poster Cafads review thread of various amps for ideas. Edited October 18, 2019 by Al.M Link to comment Share on other sites More sharing options...
Berkel Posted October 18, 2019 Author Share Posted October 18, 2019 Thank you. Link to comment Share on other sites More sharing options...
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