pragmasi
Responses from pragmasi
| Question regarding pre-amp and amp It's always been wise to switch off the power amp before the pre. The thump or click can be down to DC offset and/or the capacitor discharge time difference between the rails within the pre. Good designs of preamplifiers can reduce amplitude of th... | |
| RCA Interconnect. Van Damme are unusual for cable manufacturers in that they provide some useful specs that mean something. I use the Silver Series 55pF if I need a more than a metre of interconnect between turntable and preamp - when you actually measure the capac... | |
| Speaker cone shape For some reason, as to which one of you will no doubt enlighten me, they sound even better when the 6.5" are wired out of phase with the 8" & 4".If you've copied an original crossover design then that driver would have been reverse polarity as... | |
| hum when hooking up sub to preamp It sounds like you're describing a ground loop but it shouldn't be possible if the xlr is implemented correctly in both the pre and the sub... however it might be worth seeing if the hum is still there with everything plugged into the same outlet ... | |
| Possibly Ignorant Power Question I don't think double the power output at 4Ω over 8 is much of an indicator of how good an amplifier is... sure it's easier to make one that doesn't double but there's no reason why one that does would sound better.My advice would be not to go for... | |
| Speaker Spike Philosophy A spring is an energy store, a bit like a capacitor, so where does that energy go?.. Either back into the loudspeaker or into the floor. So the problem hasn't really been dealt with by using a spring on it's own, it will need further engineering o... | |
| Speaker Spike Philosophy My understanding is that whether you use spikes or isolation pads etc. the aim is to minimise the transfer of energy from the loudspeaker to whatever it is standing on. Spikes aim to closely couple the loudspeaker to the floor by concentrating the... | |
| how can low watt tube amps drive speakers with higher power requirements The answer is pretty much covered by the other responses here... the loudspeaker rating is how much power it will tolerate, the amplifier rating is how much power it is able to deliver. So you need an amplifier that can deliver the sound levels yo... | |
| Beatles engineers Looks like no-one here knows those guys. You might have better luck posting on the sound on sound forum which is more focussed on the recording industry. | |
| Tone control altered Balance ? I don't know how the bass control is implemented in that NAD amplifier, but if the control is a dual potentiometer then left/right tracking (balance) is never going to be great. I wrote blog post on the subject here, focussed on volume controls bu... | |
| Challenging Room Node Yep, that's a difficult frequency - a porous absorber would need to be over 4' thick (1/4 wavelength), even stuffing that into the corners is going to be pretty obtrusive. A sub array would seem to be a good choice if you have the space and wallet... | |
| Electrolytic vs poly If you have to go with electrolytics then don't forget to order bipolar ones... I'd go with cheap pp over electrolytic every time. It's fine to mix capacitor types and values. Each cap either in parallel or on its own needs to be higher than the h... | |
| Electrolytic vs poly Electrolytic capacitors (regardless of the manufacturer) produce much more distortion than polypropylene, for that reason I never use them to set a time constant (like in a crossover). They are pretty much irreplaceable in power supplies because a... | |
| The guru on fuses: @danvignau - thanks for the link to the article, I've not seen that before.The fuse he was talking about was in the speaker circuit, not the power circuit.+1 @audio2design. The text on page 6 refers to protection of the amplifier outputs i.e. the ... | |
| Do I expect too much? Maybe think about replacing the existing screws with treadlocking ones, something like these would stand a better chance of staying put. |