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shawndaiki
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Volume and distortion

Hey guys

Its been about 7 months into this amazing hobby and the questions keep me up at night. 

Ive been listening to a couple bass heavy records and it seems when I push my amplifier hard towards the 11 o'clock position the low end really wobbles the tweeters. 

Do I lack amp power or do I need speakers with better sensitivity?

I mean the holy grail of hifi is transparency where you make no excuses for the hardware and reproduce music as intended and I'm having difficulty settling on poor mastering for John Mayer's Where the Light is Live LP. 

Also how do you achieve zero noise on an analogue source? Before the platter spins I already get a fair bit of crackling and a high frequency hum when the knobs at 9 o'clock. 

Cheers guys!

Project Debut Carbon 2M Ortofon

Rega Brio R

Monitor Audio BX2

Chord Co Silverscreen speaker cables

bierfeldt
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What do you mean by "wobbles the tweeters"

Regarding your turntable, you may want to check that the ground is connected properly.  That is the most common cause for distortion. 

Additionally, the system needs to be grounded to the wall socket.  I ask this only because I helped a friend troubleshoot a similar problem and the issue was the adapter he used to plug his power strip in the wall as it eliminated the 3 prong ground.   

Are you having any issues with distortion playing any other sources like a CD player? If you are then it could be an issue with the Brio R.  If you aren't then it is most likely the ground.  This could also be causing the feedback issue with your speakers as well. 

I looked up the specs on those Monitor Audio speakers and they are relatively efficient at 90dB and that Brio R (I have one) has a very conservative 50w rating at 8ohms.  At 11:00 on your dial, you shouldn't even be close to taxing that Brio R. 

If you are getting distortion at higher volume after you resolve feedback issues from the turntable, it might be how you have your speakers set up.  What are the speakers sitting on?  Speaker stands or a book shelf?  Do you have rubber feet between the speaker and the mounting surface?  Could that front port be creating a resonance issue especially if it is on a bookshelf?  Just a few thoughts. 

shawndaiki
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Thanks bierfeldt I appreciate

Thanks bierfeldt I appreciate the input. 

I beg your pardon I meant the drivers. At high volumes the bass really wobbles quite literally and you hear the lower frequencies muffling.  That said it only happened with 3 records; John Mayer, Sigur Ros and These New Puritans. 

The system generally has no difficulty driving most of my records ranging from classical, blues, jazz and more contemporary sounds. 

My power strip is the 3 prong variety so I think we can rule that out? I will check the grounding of the TT and amp again. Unfortunately I do not have another source I can test with the amp as it's primarily for LP. 

As for the specs, I share your sentiments so far the system has been performing as well as it should. Which Is what puzzles me at the same time when I hear John Mayer's voice quite literally diffusing into noise at high volumes. It can't be?

Speakers are sitting on an IKEA table, a solid piece of wood about an inch thick, measuring 3 by 1m long, supported on two metal stands. No rubber feet and I will look into getting those. I noticed the speakers are not exactly optimally supported. 

Kindly enlighten me on what you mean by resonance issues created by the front port?

bierfeldt
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Got it...that is helpful

If the system is properly grounded, you should not hear any noise until the needle touches the record, especially at 9:00 on your volume dial.  At higher levels, a touch or airiness would not be uncommon.  If you continue to have that problem after you validate the ground, you may want to get the two devices checked out.  If you have an MP3 player or smart phone you could get (or borrow) an RCA to stereo mini plug or maybe run an RCA cable from your TV or DVD player.  This would give you a connected source to be able to test one of the other inputs.  If you contiue to get the humm and crackling on that device then it is most likely an issue with your Rega. If the other source sounds great, then you may want to get the turntable looked at. 

Rubber pads or feet may help.  If the speakers are not right at the edge of the table, you may get a bit of sound reverberating off of the table in front, especially in a front ported speaker.  This could be causing the issue as well and that is what I meant by the resonance comment.  Try setting the speakers on the floor and see if you have the same issue.  If no, then it might just be the table you have them setting on and the whole thing is vibrating. 

The other thing to question is that if it is only happening on a few LP's, is there a potential issue with those disks?  Are they old or were they poorly produces as you mentioned in your first post.  That I can't answer as I don't have the LP you have mentioned.  Do you have a friend with a turntable or can you got to a store where you can demo?  Take the record and see how it sounds.  Could be another way to troubleshoot. 

 

good luck

commsysman
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LF Problems

Acoustic feedback often occurs at low frequencies with a turntable. Very low frequencies vibrate the floor and/or the furniture your turntable sits on and feedback occurs. In that case you need to isolate the turntable from its environment better.

It sounds like that might be your problem.

Slightly warped records induce a very low frequency in the system, and that could also be happening, when certain records are played.

Placing the turntable on sorbothane pads can be helpful.

shawndaiki
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Thanks for the input guys

bierfeldt:

I looked into the grounding and also attached a CD player, both excellent troubleshooters I will engrave in memory. Nothing was wrong with the set up however I have this to share if you are a vinyl fan. http://nineinchnails.tumblr.com/post/59587808317/hesitation-marks-was-ma...

"Whilst doing this we became aware of how much low bass information there was on the record. Since that can define how loud of a level the mastering can be, we were faced with a dilemma: do we keep the bass and and have a significantly lower level record, or do we sacrifice the bass for a more competitive level of volume? The biggest issue in mastering these days tends to be how loud can you make your record. It is a fact that when listening back-to-back, loud records will come across more impressively, although in the long run what you sacrifice for that level can be quality and fidelity."

shawndaiki
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Speaker placement

I'm back again with a revelation. 

Not long after I learnt about the sumiko method for speaker placements have I been playing with the position of my speakers and what do you know?

Muddy bass response is history. And I'm talking 1/4 inch differences in placement making all the difference. 

Highly recommend the sumiko method fussy speakers or not, we're all here in the pursuit of better sound. 

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