Geraldpurchase Posted January 18, 2020 Posted January 18, 2020 I have an ASR Basis Exclusive Phono amp which is making frequent popping sounds. I am told that it is likely to be faulty Input capacitors in the battery unit. To send it ( and perhaps also its other half) to Germany and back (plus repair costs) is going to be very expensive. Does anyone know a high quality Australian (New Zealand?) repair person? Alternately, would an AC Power Conditioner (such as Furman AC-210E ??) be a band-aid solution? Any suggestions would be valued!
A J Posted January 18, 2020 Posted January 18, 2020 If it’s the caps no amount of AC filtering will make any difference. This repair should be easy. 1
mbz Posted January 18, 2020 Posted January 18, 2020 Popping on both channels? Expect not, appears to be separate power supply for L&R channels. Sending the unit(s) to Germany to replace cap(s) is overkill. If fault appears reasonably frequent then a local tech should be able to confirm that it's a battery pack problem and the offending stage etc...
Stump Posted January 18, 2020 Posted January 18, 2020 How frequent are the popping sounds ? You can bypass the battery and go direct power.
Geraldpurchase Posted January 19, 2020 Author Posted January 19, 2020 Thanks everyone! The 'static' sounds can come from either channel, or both. The noise appears as soon as I select 'Phono ' on the power amp, even when the phono amp is Off!! Selecting Line (1 or2) or Battery (1 or 2) makes no difference. I can make the popping happen by turning on anything which has a capacitor (such as overhead fan or LED lights, hence I thought 'input capacitors'. But in general play there is more of an occasional static noise, perhaps three or four times a minute. It is such a beautiful phono amp that I am in a quandary ; 'repair, or a lessor quality phono amp (can't afford a new ASR).
Telecine Posted January 19, 2020 Posted January 19, 2020 Have you changed anything in your system or changed the gain or loading options.
Quark Posted January 19, 2020 Posted January 19, 2020 Was it bought in Australia, how old is it and what did you pay for it? Might be a case under Australian Consumer Law to ask the local distributor for repair at their expense. 1
stereo coffee Posted January 19, 2020 Posted January 19, 2020 13 hours ago, Geraldpurchase said: I have an ASR Basis Exclusive Phono amp which is making frequent popping sounds. I am told that it is likely to be faulty Input capacitors in the battery unit. To send it ( and perhaps also its other half) to Germany and back (plus repair costs) is going to be very expensive. Does anyone know a high quality Australian (New Zealand?) repair person? Alternately, would an AC Power Conditioner (such as Furman AC-210E ??) be a band-aid solution? Any suggestions would be valued! Hi It could be what is called motor boating and if so, it sounds just like that. Motor boating is caused by positive feedback and can usually be traced to capacitor values that are excessive. A multimeter will be able to measure voltages and resistance. Some equipment for instance can produce such noise where voltages are insufficient. I would try to access a schematic diagram & check its performance by substituting it in your audio system with another phono amp to discern if the fault is perhaps a cartridge lead or tone arm wiring and earthing - which should be checked anyway. Hope you find the fault, and is easy to fix.
VanArn Posted January 19, 2020 Posted January 19, 2020 2 hours ago, Geraldpurchase said: Thanks everyone! The 'static' sounds can come from either channel, or both. The noise appears as soon as I select 'Phono ' on the power amp, even when the phono amp is Off!! Selecting Line (1 or2) or Battery (1 or 2) makes no difference. I can make the popping happen by turning on anything which has a capacitor (such as overhead fan or LED lights, hence I thought 'input capacitors'. But in general play there is more of an occasional static noise, perhaps three or four times a minute. It is such a beautiful phono amp that I am in a quandary ; 'repair, or a lessor quality phono amp (can't afford a new ASR). This is an instance where more homework is required. Popping noises that occur in the amplification equipment when a nearby appliance is turned on are indications that the equipment is susceptible to electro magnetic interference, (emi). This type of interference can be induced via radiation or by the mains wiring, despite the battery power supply if this is left connected to the mains . Since your ASR preamp uses an acrylic case it may be a case of requiring additional screening /shielding to prevent interference pickup. Although the preamp is intended for balance line operation this does not necessarily make it immune from emi, and more so if unbalanced connections are in use. One thing that should be tried is to remove the connections from the preamp to your amplifier and listen to the system to check that the amplifier is free from the problem. 2
Geraldpurchase Posted January 19, 2020 Author Posted January 19, 2020 Thanks everyone! The 'static' sounds can come from either channel, or both. The noise appears as soon as I select 'Phono ' on the power amp, even when the phono amp is Off!! Selecting Line (1 or2) or Battery (1 or 2) makes no difference. I can make the popping happen by turning on anything which has a capacitor (such as overhead fan or LED lights, hence I thought 'input capacitors'. But in general play there is more of an occasional static noise, perhaps three or four times a minute. It is such a beautiful phono amp that I am in a quandary ; 'repair, or a lessor quality phono amp (can't afford a new ASR).
Geraldpurchase Posted January 19, 2020 Author Posted January 19, 2020 Again, thanks everyone for the suggestions. Further information: Electrician says house wiring is fine. Power amp is fine: Old phono amp works without noise Phono amp used to work well (so shielding is unlikely to be the problem??) emi is certainly a problem: Would input capacitors be sensitive to emi? But there is also another 'static' (vs 'Thud') sound. Could faulty caps cause both thud and static??
VanArn Posted January 19, 2020 Posted January 19, 2020 (edited) Capacitors can pickup emi if they are not within shielded cases as can other components ; they act like aerials. It is common practice to fit filters to the input sections of a pre-amp and these may be simply ferrite beads or resistor capacitor networks. You may have two conditions causing you noise problem. The first is the emi from your electrical appliances and the second may be from faulty components or solder joints, etc within the ASR phono preamp. Remove all the input leads to the phono preamp and see if this stops the noises , especially from the appliances. If you still hear noises then it is likely that the noise is an indication of a fault in the preamp combo. The gain settings should be verified so that they match your phono cartridge's sensitivity, as the ASR has extra gain for moving coil pickups. If you still require a repairer I would suggest you contact Garry Cawsey and ask him if he is prepared to service your equipment. Edited January 20, 2020 by VanArn Addition. 1
Stump Posted January 19, 2020 Posted January 19, 2020 22 hours ago, Quark said: Was it bought in Australia, how old is it and what did you pay for it? Might be a case under Australian Consumer Law to ask the local distributor for repair at their expense. I guess you bought this used? The dealer and repairer is in Melbourne. Has it always had the problem since you owned it or has the problem just started. I owned a ASR Basis Phono Amp and had similar issues.
Quark Posted January 20, 2020 Posted January 20, 2020 3 minutes ago, Stump said: I guess you bought this used? The dealer and repairer is in Melbourne. Has it always had the problem since you owned it or has the problem just started. I owned a ASR Basis Phono Amp and had similar issues. If bought used, not sure much case under ACL unless there's a safety issue. @Stumpwere you able to get your ASR phono sorted?
Stump Posted January 20, 2020 Posted January 20, 2020 23 minutes ago, Quark said: If bought used, not sure much case under ACL unless there's a safety issue. @Stumpwere you able to get your ASR phono sorted? Between the dealer and Friedrich Schaefer we could not find the problem. Trying out the ASR Basis Phono Amp at another members house with no problem and selling to a new owner who also had no problems I put my issue down to interference from near by Phone Towers. 1
Geraldpurchase Posted January 20, 2020 Author Posted January 20, 2020 Again, thanks for all the interest and replies. I shall wait for the weekend to experiment more. I bought the Basis second hand from the Net (in France). I suspect the original owner might have known that something was amiss (although the dealer insists not). Anyway, I have no comeback now. I shall let you know the fruits of my experiments!
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