An Intriguing idea! Best start a new search for volume control box!!
Currently I only use cd the tt is in the shed getting ruined.
Maybe I can build one
As long as there’s a volume control, it should not only be possible, but reduce the number of noise producing components.
I wired in a potentiometer into my diy dac, and removed the JC2 preamp.
After looking at a DACmagic, it appeared to have a volume control.
What amp and speakers do you have?
I wired in a potentiometer into my diy dac, and removed the JC2 preamp.
After looking at a DACmagic, it appeared to have a volume control.
What amp and speakers do you have?
Yes, decide on the volume control you want, and mount it in a metal box with
the needed in/out connectors.
the needed in/out connectors.
https://pmc-speakers.com/products/archive/archive/fb1
I have a feeling that the problems mentioned are mostly room acoustics.
The speakers are 1M high, so they should not need any raising up higher.
No volume control on a DacMagic the amps are Rotel RC03 pre, Rb03 mono blocks and PMC FB1 modded to +
They are quite something, most people ask where the sub is, running with 2 x 180w they fill the house even at low volumes.
Its just the soundstage, sometimes bright and muddy mids that bother me but as i said its not all tracks, sometimes just sections within a track. Maybe I'm asking too much with the room acoustics?
So is it really as simple as choose a pot, mount in a box, RCA input and output?
Any pointers on cases/pots to look for?
I'm up for going pre-free
Cheapest would be an Alps from either of these two vendors:
https://www.partsconnexion.com/ALPS-68580.htmlhttps://www.parts-express.com/ALPS-...B2VYxCgbUKKVEbmJtxG6eEAOMKoXOqDRoCG-QQAvD_BwE
Could be hard-wired, but if you want a board that fits it:
https://www.ebay.com/itm/2750322181...l9Fj459ag5mfS0Ux99uwITs-If2di_3RoCaUwQAvD_BwE
Each channel would be connected like this (3 inputs selected as shown).
https://www.partsconnexion.com/ALPS-68580.htmlhttps://www.parts-express.com/ALPS-...B2VYxCgbUKKVEbmJtxG6eEAOMKoXOqDRoCG-QQAvD_BwE
Could be hard-wired, but if you want a board that fits it:
https://www.ebay.com/itm/2750322181...l9Fj459ag5mfS0Ux99uwITs-If2di_3RoCaUwQAvD_BwE
Each channel would be connected like this (3 inputs selected as shown).
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I have, can't say its made much of a difference but wifey called to say turn it down!
My volume at night is only about 10 degrees out of 315 any louder the bass is audible in every room in the house!
Literally whisper quiet
I'm currently hunting for a suitable pot located in the UK.
The idea of losing the entire pre-amp has me hooked
Doesn't RCA use a single (or twisted pair) cable for centre pin and GND?
The diagram shows 3 connections plus GND?
That looks nice and not much more than a slapped together DIY once a suitable case has been found/shipped.
Might just have to order one of those...
I'd suggest that you get that one, unless you really, really want to build one yourself,
and have done electronic construction before. Even if the shipping runs up the price a bit.
and have done electronic construction before. Even if the shipping runs up the price a bit.
How does a pre change midrange.
system works, why change
sounds like room or speaker
or some dying need to mod something that doesnt need mod
maybe system has high enough quality
you actually hear midrange artifacts in original recordings.
since some tracks do and some tracks dont.
or its magic crackle from removing capacitors
or other mods
system works, why change
sounds like room or speaker
or some dying need to mod something that doesnt need mod
maybe system has high enough quality
you actually hear midrange artifacts in original recordings.
since some tracks do and some tracks dont.
or its magic crackle from removing capacitors
or other mods
I was looking at the dacmagic and jumping the output caps shouldn’t be that hard to do. The caps are easy to find, and as long as you are always cognizant of what changes have been made, and never hot-plug the rca interconnects, you should be fine since those amplifiers have input caps.
DACs usually have four-layer boards, and can be sensitive to excess heat, that would be something that you might want to consider before making changes. The output capacitors should be left on the board, unless you have a good deal of confidence soldering, which it sounds like you probably do not. Don’t blame me if you fry your dac! The underside of the board will have the tails of the through hole capacitor leads exposed as they are soldered to their pads. A small chunk of wire held with tweezers while soldering would be my choice. A fast solder joint where heat is applied less than 5 seconds is ideal, so if you have a dirty soldering iron or really don’t have a feel for it and are dwelling for longer, I’d give it a rest before regretting it. To have the tiny chunk of wire pre-tinned with solder will help greatly. I don’t know your level of ability, so excuse me if you’re ahead of this.
The black Fujicon parts should be the output capacitors, verify this by probing the rca jacks. Don’t worry about the bypass film capacitors between the two.
DACs usually have four-layer boards, and can be sensitive to excess heat, that would be something that you might want to consider before making changes. The output capacitors should be left on the board, unless you have a good deal of confidence soldering, which it sounds like you probably do not. Don’t blame me if you fry your dac! The underside of the board will have the tails of the through hole capacitor leads exposed as they are soldered to their pads. A small chunk of wire held with tweezers while soldering would be my choice. A fast solder joint where heat is applied less than 5 seconds is ideal, so if you have a dirty soldering iron or really don’t have a feel for it and are dwelling for longer, I’d give it a rest before regretting it. To have the tiny chunk of wire pre-tinned with solder will help greatly. I don’t know your level of ability, so excuse me if you’re ahead of this.
The black Fujicon parts should be the output capacitors, verify this by probing the rca jacks. Don’t worry about the bypass film capacitors between the two.
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Just 1 question before I part with ££s
The data sheets show the following for input/output
DacMagic output impedance <50 Ohms Volts 2.1RMS
Pre amp Input 24 KOhms 150v
Power amps Input sensitivity 33 KOhms/1.0v
I understand the power amp impedance should be 10x higher than the source output so thats covered.
What I'm unsure about is the volts output of the DAC v input of the amps
What is the correlation of output V to input V?
I've found a UK based passive pre at a very low cost which has a nice casing. If it works I can upgrade the pot and RCAs to higher grade and still be within the price of the one suggested by the time shipping is included. I can test it and upgrade if required in less time than shipping from the US
Thank you for your reply.
If I had chosen to short the caps it would have been done from below the board caps left in. That way if I didn't like what I heard its simple to reverse the changes.
PS I can solder albeit I find SMDs rather tricky!
Out of curiosity if not bypassing the caps are they worthy of an upgrade? I have quite a few "decent" quality parts kicking around from modding a CD67
All good points
1 I have no idea but can't hurt to try things out
2 If I can mod the system to work better with the room issues it shall be, I'm not changing the system only to be back where I am now
3 Seems the room is the major player
4 I do like to tinker
5 Many people would agree with that
6 Yup certainly appears so
7 Only mods done are upgrading network and tweeters to +
The set up offers a very small and closed soundstage its not the systems fault but that of the room I now understand that.
If I can get the system to open up utilising the current layout, as it cannot be changed, then the system has been designed to its environment/my preferences. I have no interest selling on so tailoring it to my preference is the only way forward.
I don't wish to redesign the internal layouts just minor tweaks here and there which can be undone without lasting damage.
Thats why I've decided against brown dogs and op-amp rolling
The original caps aren’t very good, however, I wouldn’t want to just start swapping in/out until I found something either, that’s often how good devices get junked. A way to do that could be to jump the original parts and use something external until you’ve confirmed that things are well. My choice would likely be the Nichicon ES, if using electrolytic parts. Another option could be to use film caps as part of a cable assembly, externally, as part of an interconnect cable, if that wasn’t clear.
Maybe I wasn’t clear, but that’s exactly what I had suggested for jumping the caps, btw.