Crispy
very active
Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
Posts: 776
|
Post by Crispy on Feb 13, 2015 20:06:59 GMT
I have decided to build a low cost A / B switch box so that I can easily make a comparison between my V1 & V2 or any other equipment - cables etc. I have modified a drawing which I pulled from the internet but not sure if it is OK? I have used different colours to make it easier to follow where the wires go, but it still looks complicated. All help welcome if you spot any errors as I will only see what I want to see and it looks OK to me? I will be using an aluminium box, some spare 4 way phonos from the X-Can range of equipment, chassis headphone socket and a 4PDT on/on switch. Drawing below: TIA Chris
|
|
solderdude
Administrator
measureutternutter
Posts: 4,882
|
Post by solderdude on Feb 13, 2015 21:15:31 GMT
The DAC can easily drive 10 Xcan's simultaniously. You can just 'split' the signal and don't need the 4PDT switch. The only thing you need is a DPDT switch with the common contacts to the power amps and one pair going to the output of v1 and the other contact to the output of V2.
Next is exact volume matching .
Best way to do this is to use a voltmeter and a test tone between 100Hz and 400Hz (test CD or file from the internet). Don't use 1kHz it may be too high for the meter.
Connect that to the speaker out and set to V1. Set the output so you have a decent volume and measure the AC output voltage on the speaker cable. Switch to v2 amp and adjust to the exact same voltage.
Use the volume control in the DAC to control the volume and have fun.
|
|
Crispy
very active
Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
Posts: 776
|
Post by Crispy on Feb 18, 2015 21:24:51 GMT
The DAC can easily drive 10 Xcan's simultaniously. You can just 'split' the signal and don't need the 4PDT switch. The only thing you need is a DPDT switch with the common contacts to the power amps and one pair going to the output of v1 and the other contact to the output of V2. Next is exact volume matching . Best way to do this is to use a voltmeter and a test tone between 100Hz and 400Hz (test CD or file from the internet). Don't use 1kHz it may be too high for the meter. Connect that to the speaker out and set to V1. Set the output so you have a decent volume and measure the AC output voltage on the speaker cable. Switch to v2 amp and adjust to the exact same voltage. Use the volume control in the DAC to control the volume and have fun. Thanks for that Frans I have revised the drawing to what I think is correct, so if you see any mistakes let me know. I now need to get a parts list together and get the thing built
|
|
solderdude
Administrator
measureutternutter
Posts: 4,882
|
Post by solderdude on Feb 18, 2015 22:18:02 GMT
This looks correct.
That is if the RCA out is the same as the HP out otherwise the HP socket after the switch won't work properly.
|
|
Crispy
very active
Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
Posts: 776
|
Post by Crispy on Feb 27, 2015 20:56:31 GMT
Frans, the parts have arrived to build my A/B switch box. Just one question: The DPDT switch is not the same as the image I pulled from the internet and I am unsure how to wire it up correctly? the switch: I have been very busy at work, but will post some pics when I get some spare time to building it. Thanks Chris
|
|
Crispy
very active
Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
Posts: 776
|
Post by Crispy on Mar 3, 2015 20:53:42 GMT
I know Frans is very busy and I really don't know how he finds the time to sort everybody out so quickly, so is there anybody out there can tell me if this way of wiring the DPDT switch will work on my A/B box. ALL help appreciated. Chris
|
|
solderdude
Administrator
measureutternutter
Posts: 4,882
|
Post by solderdude on Mar 3, 2015 21:10:52 GMT
Sorry Chris,
Totally forgot... wanted to make a drawing
Your drawing is correct. Note that if the lever is in the bottom position the upper contacts are made.
|
|
Crispy
very active
Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
Posts: 776
|
Post by Crispy on Mar 5, 2015 21:05:51 GMT
Sorry Chris, Totally forgot... wanted to make a drawing Your drawing is correct. Note that if the lever is in the bottom position the upper contacts are made. No need to be sorry Frans, I was not in any hurry. I have now been putting the box together and will post some pics as soon as I get some spare time (and just like you I don't seem to have much of it) Thanks for the info on the switch position - I am pretty sure I would have gotten it wrong had you not mentioned it.
|
|
Crispy
very active
Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
Posts: 776
|
Post by Crispy on Mar 6, 2015 21:10:30 GMT
I decided to use an ABS box instead of aluminium partly due to cost as I wanted to keep the cost as low as possible and partly because it is far easier to drill. I don't really get any RFI so aluminium was not needed for shielding. Pic below shows the DPDT switch and headphone jack in place, the headphone jack is an old one out of my XCans to save money. RCA phonos & earth terminal in place - again from some old XCan equipment to save money How the front looks with the lid on. How the rear looks. Internal wiring completed using some old OFC microphone cable I had. This shot showing the phono splitters and some new 0.5mtr OFC interconnects. It was cheaper to buy new interconnects than to try and make my own. All I need now is some spare time to rig it up and start comparing different equipment. Enclosure £5.51 Switch £0.99 2 x Phono splitters £4.90 2x Phono leads £4.54 Total cost: approx £16 Thanks again Frans for your help
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Mar 6, 2015 23:19:43 GMT
Those look like the cheapo Cable Mountain interconnects sold by Amazon. If they are you might want to check that the left/right indicators are on the correct way. I bought a 3.5mm to RCA cable by them that had them switched. It took me ages to work out what was different. If you look at the Amazon reviews there's plenty mentions of it.
Easily fixed by removing the grub screws that hold the collars on. I say easy, the screws are microscopic! Of course, you could just test them & try to remember they're switched (or not) but that would bug me.
Gordon.
P.S. Cool project btw.
|
|
Crispy
very active
Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
Posts: 776
|
Post by Crispy on Mar 9, 2015 9:26:09 GMT
Those look like the cheapo Cable Mountain interconnects sold by Amazon. If they are you might want to check that the left/right indicators are on the correct way. I bought a 3.5mm to RCA cable by them that had them switched. It took me ages to work out what was different. If you look at the Amazon reviews there's plenty mentions of it. Easily fixed by removing the grub screws that hold the collars on. I say easy, the screws are microscopic! Of course, you could just test them & try to remember they're switched (or not) but that would bug me. Gordon. P.S. Cool project btw. Thanks for that Gordon, the cables were from CPC and they are made by Pro Signal. I have not had a problem with them.
|
|
Crispy
very active
Madrigal music is playing - Voices can faintly be heard, "Please leave this patient undisturbed."
Posts: 776
|
Post by Crispy on Mar 9, 2015 9:42:07 GMT
I managed to find a bit of spare time to put my A/B switch box into place. It was very interesting in the fact that I would say that the V1 & V2 sound almost identical? I would say they V1 was maybe? in control a bit more on some recordings. I could flick the switch quickly while a song was playing and could not for the life of me detect any difference, even my wife and daughter could not hear any difference. I matched the volume purely by ear as I had forgot to write down Frans instructions on how to match the volume exactly. So next step is to match the volume exactly and have a re-listen, but I honestly don't think I will be hearing any differences - if so they will be very small. I will then listen to the Stream Magic direct versus the V1 then V2 and see if I can hear any differences between them. It's all good fun. Frans, who has the polaris? if its Ok can I have a listen to it, I would also like to compare the sound compared to the V1, V2 and SM direct. Cheers
|
|
|
Post by hifidez on Mar 9, 2015 10:05:30 GMT
Those look like the cheapo Cable Mountain interconnects sold by Amazon. If they are you might want to check that the left/right indicators are on the correct way. I bought a 3.5mm to RCA cable by them that had them switched. It took me ages to work out what was different. If you look at the Amazon reviews there's plenty mentions of it. Easily fixed by removing the grub screws that hold the collars on. I say easy, the screws are microscopic! Of course, you could just test them & try to remember they're switched (or not) but that would bug me. Gordon. P.S. Cool project btw. Thanks for that Gordon, the cables were from CPC and they are made by Pro Signal. I have not had a problem with them. Glad I'm not the only one with the swapped chanel lead thing. Left and right chanels are pretty well arbitrary for multi track studio recordings but it was while listening to BBC R3 I noticed the first violins weren't where they usually are. And I never noticed the really tiny grub screws.. thank you. Now I can make it look right. Anyhow, the cable is very cheap, but well made. It has 'direction arrows' on it which is nice. Hate to use it back-to-front. Also printed on it is "Fully shielded high definition PC OFC interconnect cable for home theatre and digital stereo hi-fi systems". All that for a couple of quid. Good to know this analogue lead is 'digital' though. I feel better for knowing. Derek ps just checked and it is 'Cable Mountain', 3.5mm to phonos, 3m length for £4.75. Amazing actually.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Mar 9, 2015 16:57:28 GMT
Those look like the cheapo Cable Mountain interconnects sold by Amazon. If they are you might want to check that the left/right indicators are on the correct way. I bought a 3.5mm to RCA cable by them that had them switched. It took me ages to work out what was different. If you look at the Amazon reviews there's plenty mentions of it. Easily fixed by removing the grub screws that hold the collars on. I say easy, the screws are microscopic! Of course, you could just test them & try to remember they're switched (or not) but that would bug me. Gordon. P.S. Cool project btw. Thanks for that Gordon, the cables were from CPC and they are made by Pro Signal. I have not had a problem with them. Nae worries mate. They are exactly the same cables though, just differently branded. It might be worth checking them for polarity.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Mar 9, 2015 16:59:35 GMT
Thanks for that Gordon, the cables were from CPC and they are made by Pro Signal. I have not had a problem with them. Glad I'm not the only one with the swapped chanel lead thing. Left and right chanels are pretty well arbitrary for multi track studio recordings but it was while listening to BBC R3 I noticed the first violins weren't where they usually are. And I never noticed the really tiny grub screws.. thank you. Now I can make it look right. Anyhow, the cable is very cheap, but well made. It has 'direction arrows' on it which is nice. Hate to use it back-to-front. Also printed on it is "Fully shielded high definition PC OFC interconnect cable for home theatre and digital stereo hi-fi systems". All that for a couple of quid. Good to know this analogue lead is 'digital' though. I feel better for knowing. Derek ps just checked and it is 'Cable Mountain', 3.5mm to phonos, 3m length for £4.75. Amazing actually. It was when listening to classical that I first noticed something odd too. They are decent enough quality though, particularly for the price.
|
|