Dear Colin, I have just fitted stock 2R7 Panasonic 0.1% metal film resistors to replace the “green” 2R2 wirewounds in series with the Millennium tweeters in my WD25Tex speakers. I expected a change ( a bit warmer) but was not prepared for such a drastic change – is this due to the 0,5R increase or […]
Technical clinic
Found 37 results
Hello Howard. Can you ask Colin please what is star earthing and does he / will he using it in his new designs? Ta muchly J.N Peterson {Colin} Dear J.N.Peterson star earthing should be used in all analog designs, that is a single zero or earth for every component on the circuit board and normally […]
Here’s one for you electric wizards to kick around. Whilst attending a recent hifi exhibition I was doing some power cord shopping. At one particular display I was being told by a very well known cable company representative, I’ll not mention the name so it doesn’t influence any responses, that the rule of thumb is […]
Dear Colin, Zero autoformers; how to measure impedance please? I got a pair of Speltz zero autoformers recently but when I measure the total impedance, my multimeter sees only 0.4-0.6 ohm no matter what I do. It seems the multimeter could only read the DC resistance from the autoformer itself but not the total impedance […]
Dear Colin, Generally speaking, what is it that causes output transistors to blow? Do they tend to die a natural death? Bad drivers? Emitters? Problems with the rectifier circuit? Assuming there wasn’t shorted speaker wires or excessive moisture. The amp bias and the +/-77 voltage was fine before they blew. It happened on power up. […]
Hi Colin, Pls can you help me? Can I safely run a USA spec amp designed for 110v 60Hz in the UK on 240v 50Hz, with a step down transformer (but it will still be 50Hz). So many conflicting views across the web. I think a lot of people believe it can work ok the […]
Dear Colin, I’ve just picked up a Quad 405 ready for service. When I serviced my previous 405 I used the Dada kit which came with the necessary wire. Can you tell me please what size / gauge wire I should use to replace the existing power wires? Would this be suitable? http://www.rapidonline.com/design-te…0m-reels-62317 or could […]
Dear Colin, step up transformer noise. I purchased an amp from Europe that needs 240v [ I am on north American voltage].. I bought a step up/step down transformer to equalize the voltage. it works, but the transformer produces noise through the speakers, even when the amp is turned off. the transformer I bought was […]
Q: I know vintage gear isn’t your business of course but, hey, I trust your expertise and so I wonder if you can help with a component issue please? I’m doing a Sansui restoration and the main caps are Nichicon & Elna. There are many differing capacitor ranges, do you have any specific recommendations? A: […]
Hello experts. I have used audiophile fuses for years in various equipment without problem, generally appreciative of sound quality improvement. Recently, I’ve encountered problems with audiophile fuses blowing in my Coincident Turbo 845SE amplifier. At this point I’ve had two failures of Synergistic Red Quantum 6.3a 250v sloblo fuses in this amp. Recently I discovered […]
Dear Colin. I’m being a bit greedy here but two questions if I may In your opinion, what makes an Audiophile a true Audiophile? In your opinion, what do fake Audiophiles do that makes them fake? I know these two questions open the door to all kinds of jokes but I’m looking for more thought […]
Hi Colin. Just had a crackle in a left channel (nothing you’ve built by the way), fade to nothing, then that stench of death. Took the lid off my Crimson mono (a simple oblong) and all looks healthy in fact like new, the only thing that’s gone is the fuse. Could it be a mains […]
Hello Colin, please be patient with me because although I am an experienced listener I’m not very conversant with the technology that is available today. By this I mean I really just plug in and just listen. However recently I started to think about some of the units I use, In particular a Musical Fidelity […]
Hello Colin What sources and speakers does you use in development and why please? Thanks. Mike Hi Mike, Now that is a tricky question I like my old Ruark Sabres, they are old friends made for me by my old friend. I also use Spendors, and borrow others makes depending on what I am designing. […]
Hi Colin. I love your ‘clinic’. Neil promised that you might be offering education for us novices. So may I ask – have you ever thought about using braided hose to run your interconnects. I am talking about type usually found as brake lines on motorbikes and car braking systems, i was messing around with […]
Dear Colin, I recently saw a 240v integrated amp from the UK and was wondering if it is ok to use with a Step Down Converter? What are the pros and cons of using a step down device? Does it affect the sound and am I in jeopardy of blowing the transformer or ruining the […]
Dear Colin, Computer grade parts? What are computer grade parts.. such as Computer grade power-supply caps? Are these type of parts an upgrade and/or better than audiophile grade parts? For example, I’ve heard some people say, “I’ve upgraded my power supply caps in my amp to computer grade caps”. I don’t think I’d want computer […]
Q: Hello Colin. The unit in question is a Lafayette 4 channel decoder. When turning off my system, there is a popping noise from the rear speakers unless I turn the volume down on the decoder first (I’m only using the rear outputs). I’d like to eliminate the problem. I’ve searched bypass capacitor and coupling […]
Dear Colin, I’ve ordered a pair of 4-Pin DIN plugs to construct an interconnect for a Quad 33/303 system. Do both the channels need to be individually shielded, or is crosstalk not an issue here, and one could use something like this with just an overall shield? http://www.van-damme.com/14.html Failing that, can you recommend a really […]
Dear Colin, PSU caps. There are two (2) large rectangular caps at the ac inlet of the PSU of my DIY amp. They are labeled as such; 0.1uF 250V~X2. What does the X2 mean? Yeah I know, stupid question, but I’m at least looking for a intelligent answer and seeing all the past Colin’s Clinic […]
Dear Colin, power supply question. How often do we have to turn off our equipment such as power amp, pre amp. cd player , power conditioner ……? Can we leave them on for days while listening on and off or do we have to turn them off after every session of listening? As a general […]
Dear Colin, Can you tell us a little – or a lot if you wish – about the Integrated Amp design you are most proud and why please? The Claymore come to mind – the Inca Tech Claymore – it was designed on a whim for a US based company that never came back to […]
Hello Colin and may I congratulate you on your resurrection. My question is this. As it is generally agreed that as a consequence of the variation of the mains waveform systems sound different at different times of any twenty four hours, do you do your fine-tuning at a similar time each day for continuity? Or […]
Dear Colin, impedance match of preamp and main amp. I am considering mating a McIntosh Mc602 with a Bat Vk 51se. I noticed the input impedance on the Mc602 is 10K. While most Bat amps are much higher. Do you see a problem with this? It seems I remember at Stereophile I used to know […]