hi!
I'm looking for solutions to connect stereo and mono sources together on a large sound system, using FX like phaser and dub filters etc. In my first test I have gain and saturation problem, because of the Dub Filter I Think and I need some advices, maybe a buffer option in the Dub Filter ?
This is the circumstances :
All will be used in an installation for a sound system to play vinyls on powerful sound systems : turntables ---> phonopreamps ---> Pioneer Mixer DJM ---> DubPreamp ---> Filter
I want to insert an FX Filter that I assembled at the output of the Dub Preamp, just before the amps.
This is the Dub Filter : FT1 user manual
Output/input of this FT1 Dub Filter are 1/4" 6.35mm jack (10kÙ) unbalanced.
This is the Dub Preamp and all its inputs and outputs are mono : JB Audio 5 Ways Dub Preamp
In this preamp, you can use exclusively or jointly :
I'm testing to link all of them for the first time, in my home hifi context... but i'm already wondering about the limits concerning gain and saturation, in my first tests.
For my test : to connect the preamp and the filter, I use a single mono cable, because the input of the filter is a single mono 6.35mm jack. And to connect the filter to the amplifier, I use a mono jack cable on the output of the filter and a double RCA on the line input of the amplifier, with two 1k resistors before each RCA in the cable.
I set the DJM-450 to output in mono, in the internal software. The Dub Preamp is a mono preamp, he's summing signal stereo to mono. So I Output from Master Output RCA from the DJM, to the Line In Dub Preamp.
I'm very limited with gain and can't set high volume without distorsions in this circonstances. So I think the problem is the singles mono jack in/out of the Filter and the in/out impedance maybe ?
I already try to plug the filter in the send-return but the Dub Filter is not efficient enough and the the filter mode I want to use is interesting to apply (punctually) on the master, looks like a phaser. So not interesting on the send-return I think, or maybe I have the same problem... This filter is therefore interesting to connect to the output of the preamp, on the master. But in these circumstances I need to push the volume of the amplifier and the Dub Preamp to obtain a "normal" listening level, desired.
I'm looking for solutions to connect stereo and mono sources together on a large sound system, using FX like phaser and dub filters etc. In my first test I have gain and saturation problem, because of the Dub Filter I Think and I need some advices, maybe a buffer option in the Dub Filter ?
This is the circumstances :
All will be used in an installation for a sound system to play vinyls on powerful sound systems : turntables ---> phonopreamps ---> Pioneer Mixer DJM ---> DubPreamp ---> Filter
I want to insert an FX Filter that I assembled at the output of the Dub Preamp, just before the amps.
This is the Dub Filter : FT1 user manual
Output/input of this FT1 Dub Filter are 1/4" 6.35mm jack (10kÙ) unbalanced.
This is the Dub Preamp and all its inputs and outputs are mono : JB Audio 5 Ways Dub Preamp
In this preamp, you can use exclusively or jointly :
- the dual mono "Full Range" output
- and/or the dual outputs of the 5-way crossover (which works like an analog filter for the speakers, with defined cut-off frequencies that do not require the use of a DSP unlike the "Full Range" output).
I'm testing to link all of them for the first time, in my home hifi context... but i'm already wondering about the limits concerning gain and saturation, in my first tests.
For my test : to connect the preamp and the filter, I use a single mono cable, because the input of the filter is a single mono 6.35mm jack. And to connect the filter to the amplifier, I use a mono jack cable on the output of the filter and a double RCA on the line input of the amplifier, with two 1k resistors before each RCA in the cable.
I set the DJM-450 to output in mono, in the internal software. The Dub Preamp is a mono preamp, he's summing signal stereo to mono. So I Output from Master Output RCA from the DJM, to the Line In Dub Preamp.
I'm very limited with gain and can't set high volume without distorsions in this circonstances. So I think the problem is the singles mono jack in/out of the Filter and the in/out impedance maybe ?
I already try to plug the filter in the send-return but the Dub Filter is not efficient enough and the the filter mode I want to use is interesting to apply (punctually) on the master, looks like a phaser. So not interesting on the send-return I think, or maybe I have the same problem... This filter is therefore interesting to connect to the output of the preamp, on the master. But in these circumstances I need to push the volume of the amplifier and the Dub Preamp to obtain a "normal" listening level, desired.
Hi,
And what is the issue if you need to 'push' level on the amplifier or preamp?
Isn't it what it's intended for (the level knob)? 😉
Your filter is -10dbv nominal level. Typical semi pro/hifi. Do you have more info about your dub preamp than what you linked? Something with technical info?
In my view you have an issue with your gain stagging ( the way gain are distributed along your chain).
Maybe you could describe a bit more what you do with each unit in your signal chain.
In my view the djm double what your dub preamp do ( of course there is less aux and sound design tools on the djm) so i don't really get it, that said most dub sound system i've seen were kind of customised to the dj so it's not as 'standard' as in club or electronic sound system i'm more used to . A bit more explanation could help ( at least help me! 🙂 ).
And what is the issue if you need to 'push' level on the amplifier or preamp?
Isn't it what it's intended for (the level knob)? 😉
Your filter is -10dbv nominal level. Typical semi pro/hifi. Do you have more info about your dub preamp than what you linked? Something with technical info?
In my view you have an issue with your gain stagging ( the way gain are distributed along your chain).
Maybe you could describe a bit more what you do with each unit in your signal chain.
In my view the djm double what your dub preamp do ( of course there is less aux and sound design tools on the djm) so i don't really get it, that said most dub sound system i've seen were kind of customised to the dj so it's not as 'standard' as in club or electronic sound system i'm more used to . A bit more explanation could help ( at least help me! 🙂 ).
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If I compare with my usual use (DJM only), I have less gain than usual, I have to double, triple the gain at the amplifier and the Dub Preamp. The combination of DJM + Dub Preamp is purely technical, they should be able to work together without problems. DJM mixer is useful for mixing with two decks together. The Dub Preamp allows you to play with frequencies, to dub with. Everything has a use. Many sound systems combine a DJ control with their Dub control. it's not a standard but it's common all the same (less roots, more raggamuffin...). I would like to eliminate this gain problem.
I have saturation that arrives too early in relation to the audible volume. I should be able to put it louder, before I have distortions. The dub filter does not give me this problem when I remove the Dub Preamp from the chain. I have already tested the Dub Filter installed between DJM and amplifier without Preamp: a mono XLR-Jack cable to exit from the DJM to the filter (DJM configured in mono) and using a jack to RCA cable (I integrated 2 1K resistors in each wire) to connect to the amplifier. The dub filter works well without Dub Preamp or output from my Roland workstation for example
but in my opinion, this gain problem exists with the Dub Filter in the mono master chain. Because with the Dub Filter in Send-Return, the effect is less good but there is no gain problem. At the periphery of the signal (in Send-Return), no gain problem, but on the master path, gain problem.
I have saturation that arrives too early in relation to the audible volume. I should be able to put it louder, before I have distortions. The dub filter does not give me this problem when I remove the Dub Preamp from the chain. I have already tested the Dub Filter installed between DJM and amplifier without Preamp: a mono XLR-Jack cable to exit from the DJM to the filter (DJM configured in mono) and using a jack to RCA cable (I integrated 2 1K resistors in each wire) to connect to the amplifier. The dub filter works well without Dub Preamp or output from my Roland workstation for example
but in my opinion, this gain problem exists with the Dub Filter in the mono master chain. Because with the Dub Filter in Send-Return, the effect is less good but there is no gain problem. At the periphery of the signal (in Send-Return), no gain problem, but on the master path, gain problem.
lGiven it's on the master you have issue not on fx loop then it's a gain staging issue i repeat:
Without technical specifications of your dub preamp it's all a guess...
I would not be surprised if your dub preamp is able to output something in the +10dbu range ( which is almost 10db louder than the 'standard of hifi/semipro -10dbv).
This would be comfirmed by the fact your Roland workstation ( please give exact reference of gear used, it's easier to check than vague references 😉 ) don't exhibit same issue.
You make assumption about your gear, thinking it's 'purely technical and it should work together'. This might... or not. And if it works it can be different in setup to what you are used to do...
If you have saturated signal too soon ( related to what? It's too vague a description. ) then the signal driving your filter is too hot ( too high) lowering the output level of your dub preamp until there is no distortion is the answer. Or your input gain in your dubpreamp are way to high ( the volume knob next the input selector). Or the out of your Djm is too high... To know what happen we would need the technical specification of your dub preamp.
If your following stage in your signal chain (amplifier) have to make up for the level change without inducing noise: so be it. That's the reason d'etre of level knobs on amplifier ( and technically it's most always not an issue as amplifier usually have too much voltage gain anyway).
Now your cables:
_ xlr to rca. Ok, have you build it by yourself? If yes can you post a schematic of what you have done.
_Jack to rca cable: same here it seems you have done it by yourself so please include a schematic too.
Which kind of jack, TS or TRS? Why have you integrated resistors in it and how? Have you tested without the resistance before integrating them into the cable?
i'll just guess as i can't read your mind ( 😉 ): there is multiple way you could have integrated the resistance... if you implemented a divider network then you halved the output level by your choice of resistance. Worst you probably presented too low a load to the ouput stage of preceding unit in the chain ( filter, which i doubt is able to drivd the 500 ohm the resistance divider present).
If you put the resistance in series with each wire then you changed out impedance of preceding driving stage. It would worsen the frequency response and could potentially interact wrongly with your amp input.
If you tried to implement passive mixing stereo to mono then value choosen will potentially load the output stage of preceding unit presenting too low a value for it to drive without distortion...,
Here again you need to be accurate in your description if you want some help, there is too many possible scenari.
Imho, you overcomplicated things: to use mono signal on a stereo unit you just need to plug into right or left and use only the selected chanel, then go back in mono from the output of said chanel. Done. No need to sum or anything, especially if your previous unit already output mono signal ( as your djm do).
I think you integrated too many things at the same time rather than going step by step which doesn't help as it introduce too many variable at once.
So i think you should first get technical spec of your dub mixer, then a schematic of your whole chain and for every cables used. From there it'll probably be easier to troublecheck.
Without technical specifications of your dub preamp it's all a guess...
I would not be surprised if your dub preamp is able to output something in the +10dbu range ( which is almost 10db louder than the 'standard of hifi/semipro -10dbv).
This would be comfirmed by the fact your Roland workstation ( please give exact reference of gear used, it's easier to check than vague references 😉 ) don't exhibit same issue.
You make assumption about your gear, thinking it's 'purely technical and it should work together'. This might... or not. And if it works it can be different in setup to what you are used to do...
If you have saturated signal too soon ( related to what? It's too vague a description. ) then the signal driving your filter is too hot ( too high) lowering the output level of your dub preamp until there is no distortion is the answer. Or your input gain in your dubpreamp are way to high ( the volume knob next the input selector). Or the out of your Djm is too high... To know what happen we would need the technical specification of your dub preamp.
If your following stage in your signal chain (amplifier) have to make up for the level change without inducing noise: so be it. That's the reason d'etre of level knobs on amplifier ( and technically it's most always not an issue as amplifier usually have too much voltage gain anyway).
Now your cables:
_ xlr to rca. Ok, have you build it by yourself? If yes can you post a schematic of what you have done.
_Jack to rca cable: same here it seems you have done it by yourself so please include a schematic too.
Which kind of jack, TS or TRS? Why have you integrated resistors in it and how? Have you tested without the resistance before integrating them into the cable?
i'll just guess as i can't read your mind ( 😉 ): there is multiple way you could have integrated the resistance... if you implemented a divider network then you halved the output level by your choice of resistance. Worst you probably presented too low a load to the ouput stage of preceding unit in the chain ( filter, which i doubt is able to drivd the 500 ohm the resistance divider present).
If you put the resistance in series with each wire then you changed out impedance of preceding driving stage. It would worsen the frequency response and could potentially interact wrongly with your amp input.
If you tried to implement passive mixing stereo to mono then value choosen will potentially load the output stage of preceding unit presenting too low a value for it to drive without distortion...,
Here again you need to be accurate in your description if you want some help, there is too many possible scenari.
Imho, you overcomplicated things: to use mono signal on a stereo unit you just need to plug into right or left and use only the selected chanel, then go back in mono from the output of said chanel. Done. No need to sum or anything, especially if your previous unit already output mono signal ( as your djm do).
I think you integrated too many things at the same time rather than going step by step which doesn't help as it introduce too many variable at once.
So i think you should first get technical spec of your dub mixer, then a schematic of your whole chain and for every cables used. From there it'll probably be easier to troublecheck.
yes I understand I will try to be more precise in my next messages
I don't have any other information than the user manual provide and that I shared here sorry. There is no electrical information on input and output impedance for example, in this user manual. I think the additional information you would need, I need to take measurements with a multimeter, isn't it ? Forget when I talk about XLR, I was wrong, currently the tests that I carry out I do not use any XLR from the master output of the DJM, but the master RCA output and I enter in the dubpreamp with double TS jack.
I built myself the jack to rca wire. The first time I tested this filter it was without the dub preamp, I had to make a cable to connect it to the amplifier in RCA. I first tested a cable made myself, but without resistors. I had very aggressive highs, not very precise resonance peaks. Without the resistors that I added afterwards on each RCA (1k) I had distortions. With these resistors I have a filter that is no longer unpleasant for the ear. I kept this cable that I still use now by having added the Dub Preamp in the chain.
1st photo : the chain
2nd : rca-jack schematic with sum-resistors
I can't answer with more details at the moment but I will continue my tests this evening, with other cables and I could take impedance measurements.
I don't have any other information than the user manual provide and that I shared here sorry. There is no electrical information on input and output impedance for example, in this user manual. I think the additional information you would need, I need to take measurements with a multimeter, isn't it ? Forget when I talk about XLR, I was wrong, currently the tests that I carry out I do not use any XLR from the master output of the DJM, but the master RCA output and I enter in the dubpreamp with double TS jack.
I built myself the jack to rca wire. The first time I tested this filter it was without the dub preamp, I had to make a cable to connect it to the amplifier in RCA. I first tested a cable made myself, but without resistors. I had very aggressive highs, not very precise resonance peaks. Without the resistors that I added afterwards on each RCA (1k) I had distortions. With these resistors I have a filter that is no longer unpleasant for the ear. I kept this cable that I still use now by having added the Dub Preamp in the chain.
1st photo : the chain
2nd : rca-jack schematic with sum-resistors
I can't answer with more details at the moment but I will continue my tests this evening, with other cables and I could take impedance measurements.
I tried to put the filter first just after the DJM mixer. It's better. So now I have this chain :
Turntable -> RIAA Preamp -> DJM Line In -- DJM RCA Master Out (DIY summing cable x2RCA to x1 Jack 6.35 mono) -> Filter in -- Filter Out x1 (jack 6.35 mono) -> Dub Preamp Line In 1 -- Full Range Dub Preamp Output (x2 Jack 6..5 to x2 RCA) -> Amplifier RCA Line In
it's better, filter works better and gain is better too. So I put the summing diy cable on the output of the DJM (this cable has two 1K summing resistors). Then the filter output go to the Line 1 input of the preamp with only one jack 6.35 mono. is there a way to get more gain out of the filter so that you can go into the dub preamp with all the gain available? Line 1 has two mono inputs into the Dub Preamp. Or is there theoretically no gain loss, even with only one input at the preamp? From the x1 mono output jack of the filter, how to enter the preamp on the two Line 1 inputs? is it necessary now?
Turntable -> RIAA Preamp -> DJM Line In -- DJM RCA Master Out (DIY summing cable x2RCA to x1 Jack 6.35 mono) -> Filter in -- Filter Out x1 (jack 6.35 mono) -> Dub Preamp Line In 1 -- Full Range Dub Preamp Output (x2 Jack 6..5 to x2 RCA) -> Amplifier RCA Line In
it's better, filter works better and gain is better too. So I put the summing diy cable on the output of the DJM (this cable has two 1K summing resistors). Then the filter output go to the Line 1 input of the preamp with only one jack 6.35 mono. is there a way to get more gain out of the filter so that you can go into the dub preamp with all the gain available? Line 1 has two mono inputs into the Dub Preamp. Or is there theoretically no gain loss, even with only one input at the preamp? From the x1 mono output jack of the filter, how to enter the preamp on the two Line 1 inputs? is it necessary now?