hifi57audio
Responses from hifi57audio
| Loud thump when I power on or off Hiend2 is close. The turn on/off thumps are caused by a rapidly climbing or decaying DC signal component being coupled to your speakers. This occures as the ciruit RC constants are charged/discharged. Most equipment is designed as to not allow thi... | |
| Can the sound of SS amp deteriorate over time?? Yes it can, for a varity of reasons. The main resevoir caps(the large cans) in most high end amps are charged thru a very low series resistance. The current surge upon turn on present a "shock" to the cap, and over time causes excessive DC leakage... | |
| Vacuum tube tester repair Thanks everybody for their responses. Although it's not showing in this thread, one of these links connected me to a Mr. Kennedy at alltubetesters.com . He seems to be a freindly individual, and his prices are reasonable. In addition he offers tec... | |
| Electrical issue The ideal ground would be at 0v DC, 0hz to light AC, to earth. All voltages are ultimatly referenced to ground. If you have trash on the ground it can couple to your system. | |
| Electrical issue 120hz would be the ripple component frequency of a rectified power supply. Trying to determine if it's an electrical or electronics problem. The PS unit should have isolated the equipment from AC, since it regenerates it's own. Did you try it with... | |
| How To Match Power Tubes By the by, does anyone know someone who repairs Hickok equipment? There is an open circuit somewhere and it won't measure pentodes properly. There's probably a thousand solder joints in this thing, and 1/2 mile of wire. I would have take up methap... | |
| How To Match Power Tubes All Hickoks and all the vintage testers test at to low a current to match tubes properly. With some tubes you can set the bias and transconduction range at a point where you can get some meaningfull measurements, some you can't. If the amp has fix... | |
| Need Mono Blend - Will This Work? You can also use any record with stereo test tone band, Reverse cardridge leads on one channel, Y it out; and use headphones, makes the job a little easier. | |
| Electrical issue RFI is not the prob. Does the hum have a bit of a buzzing component to it? Two types;60&120hz. 120 has this really anoying buzzing to it,60 is rather bassey of course. A mic and a o-scope, sure would be handy. Dumb question,is a TV,or some oth... | |
| Preamp with intermitting Bzzz where to start? Get Someone you don't particulary care for to move wires or components around while the unit is running so as to find a bad solder joint. | |
| CD output voltage too high for preamp: what to do? Restock- Beats me, unless they are designed for pro use. Sound reinforcement/studio equipment often employ a matched impedance interface to optimize power transfer. If thats the case it would almost certainly be offered with a balanced connection ... | |
| CD output voltage too high for preamp: what to do? Almost forgot, as concerns input impedance; R total should be selected as to maintain yours. For instance if it's 50k and you plug a 50k attenuator into the inputs, your CD player will see a 37k load.( when set for 1/3 attenuation) and will vary o... | |
| CD output voltage too high for preamp: what to do? The equation for voltage dividers is: (shunt/(series+shunt))=voltage reduction factor. VRF x Vin=Vout... (Vin/Vout)log20= db attenuation Put simply in your case, dropping from 2.25 to 1.5 is a voltage reduction of exactly 1/3. So, Series R would e... | |
| CD output voltage too high for preamp: what to do? Best solution would be to have Ayre, or someone with the schematic to reduce the output of the CD player. I have no idea of the topology of the output circuit, be it discrete or op-amp based. I am assuming its solid state, maybe not. If it's tube,... | |
| Ground Loop Problem - Stumped I Haven't the time right now to read all the responses, so forgive me if this has already been addressed. The hum you describe is likely 120hz(full wave rectified 60hz line freq) picked up from the power supply. The difference in voltage drops bet... |