IgglePiggle Posted May 29, 2023 Posted May 29, 2023 Greetings I decided to revive my vinyls and setup up a new system before the only thing Ill be hearing is the dinner bell in the nursing home. I had a pair of Mordaunt Short Avant 906i speakers and a Mordaunt Short 907W sub from a previous home theatre setup I bought new a Yamaha A-S701 Amp and Audio-Technica LP120XUSB Turntable Amp is set to "high" impedance Turntable is switched to "phono" and plugged into amp "phono" And yes its bi-wired Sound is very bland and any sort of volume, the cones go nuts Also turning on the sub and it emits buzzing and other horrible noises ( it worked fine before ) What am I missing here ? Thanx
Jakeyb77_Redux Posted May 29, 2023 Posted May 29, 2023 That turntable has a built in phono stage. If you’re using that you don’t use the phono input on your amp. You use the Aux input or similar. Otherwise you’re plugging a phono preamp into a phono preamp. 2
Keith_W Posted May 29, 2023 Posted May 29, 2023 Check that your turntable doesn't implement the RIAA curve before output (the name "USB" suggests it has some electronics on board). If you apply the RIAA curve twice, it will massively boost the bass and cut the treble producing the symptoms you describe. Plug your turntable into any other input on your amp except "phono" and see if that solves the issue. 1
muon* Posted May 29, 2023 Posted May 29, 2023 (edited) Turntable Output Level Pre-amp PHONO: 4 mV nominal at 1 kHz, 5 cm/sec Pre-amp LINE: 240 mV nominal at 1 kHz, 5 cm/sec So he has the Phono setting on the table into the phono input of the Yamaha so all good there. Edited May 29, 2023 by muon*
Jakeyb77_Redux Posted May 29, 2023 Posted May 29, 2023 Also I would change the wiring of your amp. That’s not bi-wired. I would run 2 channels off the amp and use speaker wire to jump the terminals at the speaker end. 1
graham121 Posted May 30, 2023 Posted May 30, 2023 Definitely curious as to why both speaker a and speaker b outputs are hoping to the same single set of speakers.
IgglePiggle Posted May 30, 2023 Author Posted May 30, 2023 2 hours ago, graham121 said: Definitely curious as to why both speaker a and speaker b outputs are hoping to the same single set of speakers.
graham121 Posted May 30, 2023 Posted May 30, 2023 1 hour ago, IgglePiggle said: Thanks for showing that, was not aware the Amp had that option on the speaker select switch. 1
Snoopy8 Posted May 30, 2023 Posted May 30, 2023 Some sound advice above. Let me add by asking where the setup is placed in the room. The room has, by far, the biggest influence on SQ (sound quality). Please provide details of the room and, if possible, a sketch of where the speakers are and the listening position.
ENIGMA Posted May 30, 2023 Posted May 30, 2023 The video was useful. Might also be some speaker vibration feedback getting into the turntable but the way the cones a moving it looks strange and somewhat electrical. Try without biwire with a different source on this amp (no T/T) the T/T with a different amp if you have one. either with and without the subwoofer. 1
SGS Posted May 30, 2023 Posted May 30, 2023 Try using better RCA cables. As your using the phono output it has a very low signal and is quite susceptible to interference. Really should be using something with good shielding which may be causing sub buzz. Also try without earth connected.
Analogsound Posted May 30, 2023 Posted May 30, 2023 I think you have a problem with subsonic filters in your systems First, you try connecting the phono cable to the right input in the amplifier Second, try to move the turntable far away max as you can with the amplifier If you can't fix it try to read the link below https://forums.stevehoffman.tv/threads/are-subsonic-filters-important.872756/ 1
IgglePiggle Posted May 30, 2023 Author Posted May 30, 2023 Update Thanx for all the responses So far the only thing I have done was set the TT to "line" and plugged into "line 1" on the amp. Bingo .... all the gremlins were gone ..... sub working normally Still some tweaking to do to improve the sound The speakers were sitting flat on the wooden floor so I now have spikes for them and as mentioned below some better cables for the TT I think the USB/preamp setup in this TT is definately a bit suspect ..... while researching TTs on youtube I saw where people were even removing the whole circuit board. I will run the CD player and try with a "normal" speaker connection ,etc and see how it goes also. As for the room , its the original living room of a 99yr old Californian bungalow .... currently the dining room but being transformed to the listening room. The dining table/chairs will eventually be replaced with a lounge/sofa/couch 12 hours ago, SGS said: Try using better RCA cables. As your using the phono output it has a very low signal and is quite susceptible to interference. Really should be using something with good shielding which may be causing sub buzz. Also try without earth connected. That was always in the game plan and they arrived yesterday .... .... the cables that came with the TT are pretty poor.
Quark Posted May 31, 2023 Posted May 31, 2023 If your system has a rumble filter for the turntable, try using that. Given you're on floorboards, may need to use a wall mount for the turntable. 1
Keith_W Posted May 31, 2023 Posted May 31, 2023 I was reading a thread on another forum yesterday about the dangers of using spikes with wooden floors. In that forum, the OP replaced his spikes with springs and noticed an immediate improvement in the clarity of his system. The spikes couple your speakers to your floor, effectively turning your whole floor into a giant resonating cabinet that "stores energy and releases it in a haphazard way fractions of a second later" (to quote someone else in that thread). Spikes are OK if your floorboards lay on concrete but you may be better served by going with springs or foam instead since you mention you live in a Californian. My architecture is a bit rusty but I think those have suspended wooden floors?
IgglePiggle Posted May 31, 2023 Author Posted May 31, 2023 1 hour ago, Keith_W said: I was reading a thread on another forum yesterday about the dangers of using spikes with wooden floors. In that forum, the OP replaced his spikes with springs and noticed an immediate improvement in the clarity of his system. The spikes couple your speakers to your floor, effectively turning your whole floor into a giant resonating cabinet that "stores energy and releases it in a haphazard way fractions of a second later" (to quote someone else in that thread). Spikes are OK if your floorboards lay on concrete but you may be better served by going with springs or foam instead since you mention you live in a Californian. My architecture is a bit rusty but I think those have suspended wooden floors? Yes I was wondering how the wooden floor would affect things .... and you are correct , its a floating floor ! Im "changing" 1 thing at a time and Ive just installed the spikes and played a few tunes ..... one thing I added was some of those stick on furniture pads onto the discs that the spike sits in. And what a difference that made ..... some nice clear bass tones ! The sub is on spikes directly on the floor and I have a set of discs on order for it also so Ill do the same there and I think it can only improve even more 1
muon* Posted May 31, 2023 Posted May 31, 2023 5 hours ago, IgglePiggle said: So far the only thing I have done was set the TT to "line" and plugged into "line 1" on the amp. Bingo .... all the gremlins were gone ..... sub working normally The manual must be wrong then as Line for the table says 240mv, and Phono setting 4mv
Jakeyb77_Redux Posted May 31, 2023 Posted May 31, 2023 5 hours ago, IgglePiggle said: Update Thanx for all the responses So far the only thing I have done was set the TT to "line" and plugged into "line 1" on the amp. Bingo .... all the gremlins were gone ..... sub working normally Still some tweaking to do to improve the sound The speakers were sitting flat on the wooden floor so I now have spikes for them and as mentioned below some better cables for the TT I think the USB/preamp setup in this TT is definately a bit suspect ..... while researching TTs on youtube I saw where people were even removing the whole circuit board. I will run the CD player and try with a "normal" speaker connection ,etc and see how it goes also. As for the room , its the original living room of a 99yr old Californian bungalow .... currently the dining room but being transformed to the listening room. The dining table/chairs will eventually be replaced with a lounge/sofa/couch That was always in the game plan and they arrived yesterday .... .... the cables that came with the TT are pretty poor. Good to hear. I’ve had two of these turntables and the ones that first came out (2013)were built a lot better than the newer one that I have (2021). I think bypassing the in built phono at the switch is a must as it’s always been dodgy. As you said a lot of people bypass the whole circuit altogether. I haven’t gone to that length 1
vintagejapan Posted May 31, 2023 Posted May 31, 2023 Place the sub in a big foam platform. Works wonders
ENIGMA Posted May 31, 2023 Posted May 31, 2023 3 hours ago, IgglePiggle said: Yes I was wondering how the wooden floor would affect things .... and you are correct , its a floating floor ! Im "changing" 1 thing at a time and Ive just installed the spikes and played a few tunes ..... one thing I added was some of those stick on furniture pads onto the discs that the spike sits in. And what a difference that made ..... some nice clear bass tones ! The sub is on spikes directly on the floor and I have a set of discs on order for it also so Ill do the same there and I think it can only improve even more I have wheels under my speakers because at around 100kg each i wouldn't be able to move them.
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