Can you recommend a good amp/receiver upgrade?

Thanks for the recommendations. Just wanted to provide an update for those interested.

A nearby forum member privately offered to sell me a vintage Sansui 9090 receiver, so I opted to try that in part because it was cheaper. I just got it hooked up tonight - with totally new cables - and to my total surprise, I have the exact same problems with both the Oppo playback and the turntable. Even more strange is that through this amp, the phono signal sounds weaker and even more distorted throughout (more like what I heard through headphones).

I need to spend more time figuring this out, but I've definitely determined that once again, I've got not one problem but multiple. I really am cursed. For one thing, my KEFs are not handling considerable volumes or bass well at all. Having replaced both the receiver and the cables, there is no other possibility. But more disturbingly, something is *really* wrong in my phono stage as well. I'm going to do more troubleshooting offline as clearly this is getting beyond a simple issue I can ask for help with when someone can't hear the issue or see the setup. I will report back when I know for sure where the phono issue lies.

 

To my knowledge, there are no such settings on this preamp. There is certainly nothing at all on the exterior to change anything other than a switch for MC or MM. It was sold to me because it was "easy".

 

You eliminated the amp which is huge. Very that your speakers are wired correctly. As silly as it sounds, have you made 100% sure that the same strand that plugs into the positive slot of your speaker is plugged into the positive slot of your amp (and same with negative, of course)? Out-of-phase speakers can sound hollow and distort easily. Is the wiring you're using of gauge 14 (or bigger) or is it a small gauge? Note that the bigger the number, the smaller the wire so if you're using gauge 20 wire, it'll be pretty thin! Be mindful that some manufacturers will make thick wires with very thin strands of copper inside. Using a thin gauge could create this distortion. Fortunately, non-audiophile brand speaker wire is real cheap.

Power is the last remaining factor. Are you using a power conditioner, a UPS, a surge protector, or a power bar? If so, what happens if you plug your amp directly into the power socket?

 

Yup, speakers are absolutely wired correctly and with good cables both before and now. I wonder if I've had a defective pair all of this time or the Q900s simply don't hold up with loud volumes for anyone. A review I read said they were "somewhat intolerant" of higher levels, but I'd describe what I'm experiencing more as considerably intolerant. Hmmm. I can live with the periodic distortion I'm hearing from the Oppo though. Wasn't the worst thing in the world. The sound I heard from the phono stage was pretty awful, however.

I just realized/remembered that the Sansui has a built-in phono preamp, so I'm going to try that as well to see what results I get from the turntable. Just need to wait for longer RCA cables to arrive to test that as what I have now will not reach.

I'll try the power test as well, but what I'm now hearing with the Sansui receiver is a pretty obviously "wrong" sound.

Oh, I should note that while a vintage receiver, it was apparently completely re-capped.

 

What is their gauge, though? Good cables can be of gauge 20 and your speakers would easily distort because cables of that caliber aren't made for that much power. That's why I (and you) really need to know what gauge your speaker cables *actually* are. It's an especially valid and essential question in this case. If you don't know, it's a likely possibility you're running too high a gauge for your gear and listening habits. Don't dismiss this component. It easily could be the source of all your problems!

Where did you read that? They're rated all the way to 200W and your Sony can go to a bit more than only half of that ceiling.

Hell, the Stereophile reviewer stated "I was comparing, at rather high levels, the sounds of two disc players playing the organ compilation Pipes Rhode Island when I realized that the Q900s were shaking the room with authority." Doesn't sound like someone who feels they distort easily.

As for a defective pair, no. That's an almost impossible scenario. I could see one defective speaker as being a possibility but 2? Doubtful.

No point in trying that, I'm afraid. Even if it sounds much better using the internal phono preamp, you'll still get that distortion since the Oppo displayed some.

This is just me but I'd never buy a vintage receiver for many many reasons.

In your case, power is a main consideration. Most of these 70s vintage Sansui, Marantz, Kenwood and other brands were lowly powered. You like to listen to music loudly and have speakers with low sensitivity ratings. Considering an underpowered vintage receiver is lunacy! That is a severe downgrade from the get-go.

You don't know who did the upgrade or what their qualifications are. Their work could be terrible. The chosen replacement caps could be just any cheap ones. What hasn't been changed could go at any time and while true that can be said of any unit, components which are 30-40 years of age are at much greater chance of dying. If/when it happens, you'd be on the hook for the work and parts to make it run again. No warranty for the work which was previously done either.

I could go on but you get the gist. Considering your luck, I would *strongly* recommend you stick with components which are recently made and covered with a warranty! If there's a problem, you can then get it fixed and for free. Why tempt fate when you've had such a tough run so far?

 

I love new gear. I have never had a problem in 40+ years of owning decent audio gear. I did buy a slightly used DD Technics SL-QL1 from a buddy back in '85. It's still in use today with nary an issue. I buy new stuff when I want to put together a system, something that has a proper built in phono stage (like the Marantz integrateds, a recent purchased 1210GR turntable, a new VM95ML cart and, after doing the set-up, it sounds amazingly good with ZERO issues playing through a Yamaha RX-V990 and Celestion DL-8 II's. The latter two pieces of gear were also bought new but a loooong time ago.

I remain convinced that too may music lovers ruin their experience with music by getting things complicated. KISS and you will enjoy great sounding, no drama music whether, streamed, CD, or LPs. It truly isn't rocket science although some here make it seem like it is.

 

The OP is experiencing an issue he believed might be solved by buying another amp but is unfortunately still encountering the same problem.

 

Thanks again for the help, Strat. I looked them up and I was previously running 14 gauge speaker wire, bi-wired (a configuration recommended by the dealer). It was these cables specifically:

https://www.amazon.com/gp/product/B00SPVIPAI/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

The forum member who turned me on to the Sansui gave me Blue Jeans cables (not bi-wired), but I'll have to confirm the gauge with him as I'm not familiar enough to guess based on looking at them. They ain't thin, though. Same exact issue with the Oppo - just at certain points if the volume is too high, I get noticeable distortion in the highs (like before, I again tested with Steven Wilson's stereo remix of Jethro Tull's Stormwatch). Taking the subwoofer away made clear that the woofers pump really noticeably when decent bass is applied, and specifically on that recording, the drums begin to distort at high levels too.

As for the wire gauge, I will note that while I freshly stripped the Blue Jeans cables he gave me, the wire was a bitch to fit into those old spring loaded connectors and a few strands wouldn't make it in. Since this would seem to be an issue based on your comments, I will see if I can find connectors I can use with the lower gauge cables to insure the best connection.​

I am in no way dismissing what you're saying, and believe me, I totally hope that problem could be as simple as the gauge of the wire used. But it sure sounds like the more troubling distortion I'm getting from the phono stage is a different problem entirely. I'm not sure if I posted it here originally, but when I plugged headphones into my previous Sony amp, the distortion was almost throughout on a new record and two more that should be absolutely clean. What I'm hearing through this amp from the phono stage (which is coming off brighter in sound than the Sony) is more akin to what I heard in those headphones. A pair of headphones that barely output any low frequencies, BTW. Which makes me think that since this amp is brighter and I no longer have a sub, maybe when I was running the Sony with the subwoofer, I was just masking issues I had in the upper frequencies but didn't notice them so much because I had such good results from lower frequencies.

Anyway, I now have to troubleshoot these as two separate issues.

Note that the seller is kind enough to offer to take the amp back if it doesn't work out for me, so it was well worth trying. That said, it made me feel that even if getting a new amp may be wise in the long run, it certainly is not apt to solve either of the two problems described above.

I'd like to think that what csgreene says about this not being rocket science is true. But for some reason, I'm having a hell of a time getting what I've paid for.

 

Strat - If you wanna recommend specific cables to try that will satisfy the test, please feel free. Preferably something I can get shipped fast. I've thrown so much money at this, that it ain't gonna kill me to try yet another set of cables if that will help figure this out.

 

without reading through the thread did you reverse the interconnects coming from your phono preamp?

also- what input are you connecting to on your receiver?

 

People often have trouble using equipment that was not designed to work well together in the first place. I don't know if that's what you have here, but from re-reading some of your posts and your new ones it sounds like you are dealing with multiple issues and you really need to figure out a way to isolate each variable.

That means only changing one thing at a time, and only focusing on one source at a time. I would probably troubleshoot the digital/CD/BR source first, since that is going to be easier than troubleshooting LOMC vinyl playback.

If you want to try swapping in other pieces of equipment I would probably stick with things that are easy to return, no questions asked. That means sticking with retailers like Crutchfield or MD, or reading the fine print from any other retailer. I would also avoid things like obscure boutique brands if you want to try a new integrated amp or something. Keep it simple.

I also wouldn't go down the rabbit hole/scam of overpriced cables. Unlikely to fix any problem you are having. The cables you have already should be checked to make sure they are working okay. You can probably do that with a cheap multimeter or something.

RE: your speakers distorting, I don't know them - but most speakers have a threshold where they will distort some no matter what. Not only that, but most speakers being made today, that don't cost king's ransom, will have cabinets that resonate and make the distortion worse at certain volumes. Combine that with an imperfect room (which most people have), less than ideal placement, etc. and you get more problems.

 

Frankly since replacing the receiver, I have not redone any troubleshooting with the phono stage but will continue to do that over the next several days. What I heard last night just depressed me, so I decided to call it quits for the night.

As for what input I use, I'm not using the phono input. On the Sansui, I'm using the AUX input.

 

understood and sorry for the bummer results.
next steps would be to reverse the cables one at a time phono to preamp, preamp to amplifier- BUT keep the same left / right input consistency. You may have a bad or noisy cable if the sound moves to the other channel. long shot but worth the effort.

 

I wish I had more experience with similar equipment to know what to expect, but what you say here kinda resonates with me. I am remembering now why I bought the subwoofer to begin with. When I first got the KEFs 3 years ago, I told the dealer they were distorting at higher volumes, and his response was "That's weird; that shouldn't happen." He didn't have much else to offer though. So in my typical fashion of just wanting to make a problem go away quickly, we agreed that buying a subwoofer would keep the speakers from working so hard.

I most certainly have an imperfect room which also means less than ideal placement. You will get no argument from me on that. I will observe more to see if the cabinet seems to be the source of the rumbling when the bass is heavy. I do NOT have the speakers raised in any way - they are sitting directly on a hard wood floor. So that could explain that, and that's something I can easily address. The distortion I have heard from the digital sources (the high frequencies at loud volumes) sounded like it was coming directly from the tweeter to me. Would this be solved by a better room and better placement causing me to not need to turn the volume up so loud? Entirely possible. I won't know that until I can get a better room though (which should happen in a year or so).

 

You have the Kef q900 floorstanding speaker? Were they new in the box when purchased or did you buy used/demo/open box? Is it the same pair you auditioned that were distorting in the store?

Looking at the Stereophile review and measurements of this speaker I think it should play quite loud without distorting. Although fairly efficient it does have a load that drops below 4 ohms so I would expect it to need better and more powerful amplification than you’ve given it to do so. The reviewer used a robust Bryston amp.

Let me also review to make sure we have it right. You initially said this was left channel only. Is it still? You are hearing the problem with digital and vinyl? You can also hear it on both sources through headphones? Is it one channel or both channels on on headphones?

 

Yes, the KEF Q900 floorstanding speaker. These may very well have been the demo pair - I seem to recall they were the last pair the dealer had. I did NOT experience any distortion in the store, but I didn't have them as loud there, so that's inconclusive.

Please forget the "left channel only" comment made previously. I got that wrong somehow. Turned out the problematic instruments on two recordings I tested then just happened to be more separated to the left channel in the mix. This definitely happens on both channels.

Let me do more troubleshooting with the vinyl source tonight before I comment further there, as I want to re-test everything with the new amp and without the subwoofer.

So for now, what I know for certain is that the KEF Q900s give me significant distortion in some highs when the Sansui 9090's volume control is at about 11 o'clock with a digital source played through an Oppo BDP-83's analog outs into the AUX jack on the receiver. This exact same behavior occurred with a lesser Sony multichannel AV receiver (110W per channel) when the volume was up near max (which is actually about as loud as 11 o'clock on the Sansui). Not only was the receiver swapped out, but so were the speaker cables. Same exact problem on the same moments/instruments.

I also know that if I kick the bass up +2 on the Sansui to actually give me some decent bottom end, there is additional distortion/rumbling in the bass frequencies (drums on the Jethro Tull Stormwatch stereo mix I played/tested last night).

Let's keep it at that for now until I can again troubleshoot the vinyl issue.

 

That is most likely amplifier clipping you are hearing due to not having enough power for the volume with your speaker.

 

Too often, I've seen the WPC stat liberally slapped onto amps leading to some strange experiences where I was expecting a lot more power than was actually on tap.

I do believe a higher quality amp with enough juice would make this work, hence why I initially suggested the Outlaw whose power rating is not an exaggeration manipulated from creative math.

 

+1

Neither of OP's amps has rating for 4 ohms. The speaker's can dip down to 3.2 ohm.

 

Playing devil's advocate, KEF recommends 8 ohms.

 

Receiver swapped out so not that. Not cables or IC's.

Still on suspect list:

1. Cart and or cart alignment
2. Phono stage
3. Speakers

Either way you slice it, with your descriptions, sounds like you could benefit from some better speaks. Difference between phono and all other inputs can easily be figured out with remounting your old cart, or plugging in a new phono stage that can do MC.

As you likely know, Art9 set up properly can sound better than your Oppo.

 

This is the guy who sold Izgoblin the receiver. The Sansui is 110 wpc, and was brought back up to factory spec by a McIntosh tech around 2 years ago. Before he took it home, we tested it on a pair of Dahlquist DQ20's, which are notoriously difficult to drive, and we cranked it up to pretty loud levels, and all seemed fine. The speaker cables are Bluejeans 12g wire. I don't 'think' it's the receiver, but at this point, who the hell knows lol. This is definitely a really weird issue...

I'm going to run over to his place this weekend and help him troubleshoot the issue. I'll bring another amp, cables, and maybe even a pair of bookshelf speakers. Unfortunately I don't have a mc phono stage to bring. We'll get to the bottom of this one way or another!

 

Funny, because I was JUST reading nearly those same exact words in a response to a similar complaint on the Q900 listing on Amazon. Any chance that was you?

If this is the issue, then this brings me back to my original question on equipment matching. Given the ratings of the KEFs, what specs should be I looking for in a receiver? And if I'm buying another one, what about my cart and preamp? How do I make sure I'm getting something that matches those so I can avoid any such clipping?

 

Since the problem occurs when using another source, it's unrelated to the cart, phono preamp, or the turntable.

 

That's kind of you.