Headcoat

Graphic Equaliser Question

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19 minutes ago, uzzy said:

bugger - the difference of couse is a tape loop is fed by whatever is selected on the preamp .. yes I see I have failed in that you would have to select the line input to play back from the EQ and that would have no signal - so you would need to get a separate phono stage and plug it into the back of the ADC .. I have failed ... again 

Took me a while to get my head round it!

I would have suggested a quick mod to add power amp input sockets, but it's all electronic switching in the input stage and without a schematic (can't find one online) there's no guarantee it's straightforward. The pre-amp out is not likely to just be a connection between the pre and power stages, but may well be a 'spare' channel from an opamp.

Simplest way seems to be 'as you are' which would mean a fair bit of plugging and unplugging (eq between phono and amp or between DAC and amp). Second alternative means more cost: either a separate phono stage, so the phono stage and the DAC into the eq, and the eq into the amp. This would, however, need an eq with multiple inputs. Third alternative, buy a separate power amplifier and put the eq between the pre outs and the power amp.

Fourth alternative, sell the 368 and replace it with a separate pre-power combination or an integrated amp with a pre out and power in connection.

The tape out-in won't work, because it's the same issue: the tape out is OK (it's unattenuated line level), but the tape in means there is no other input available.

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32 minutes ago, uzzy said:

bugger - the difference of couse is a tape loop is fed by whatever is selected on the preamp .. yes I see I have failed in that you would have to select the line input to play back from the EQ and that would have no signal - so you would need to get a separate phono stage and plug it into the back of the ADC .. I have failed ... again 

Not at all, was worth considering. The turntable currently seems to work via the cheapo Behringer eq I've got. For now though I can only plug in either the DAC or turntable direct to the one input on the eq, hence originally was looking for an eq with two line ins and two lines outs. But, I'm not convinced running a turntable straight into the eq and then onto the phono pre-amp in the NAD is ok e.g. loading issues when the signal reaches the phono pre built into the NAD.

If there's no issue with eq'ing the turntable before the phono pre-amp then I could simply buy a quality RCA splitter/selector to go before the eq, run both the turntable and DAC (DAC is used for CD transport and Spotify stream form Chromecast audio) into this and select which one feeds the eq; then another splitter/selector to go agter the eq to select if the eq's signal goes to the phono or line 1 input on the NAD.

The advantage of the NAD also having it's own onboard DAC is I would still have the option of playing CD's via this without any connection to the eq, the CD transport has component and optical outputs, as current one runs to the external DAC and one straight into the NAD's DAC.

Very tempted by the ADC, just need to make sure running a turntable into the eq before the phono pre-amp is all good on an electronics level first, before making final decision.

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3 minutes ago, rabski said:

Took me a while to get my head round it!

I would have suggested a quick mod to add power amp input sockets, but it's all electronic switching in the input stage and without a schematic (can't find one online) there's no guarantee it's straightforward. The pre-amp out is not likely to just be a connection between the pre and power stages, but may well be a 'spare' channel from an opamp.

Simplest way seems to be 'as you are' which would mean a fair bit of plugging and unplugging (eq between phono and amp or between DAC and amp). Second alternative means more cost: either a separate phono stage, so the phono stage and the DAC into the eq, and the eq into the amp. This would, however, need an eq with multiple inputs. Third alternative, buy a separate power amplifier and put the eq between the pre outs and the power amp.

Fourth alternative, sell the 368 and replace it with a separate pre-power combination or an integrated amp with a pre out and power in connection.

The tape out-in won't work, because it's the same issue: the tape out is OK (it's unattenuated line level), but the tape in means there is no other input available.

Not selling the 368, I love it and the built in headphone amplifier is excellent!!! Waht do you reckon on two RCA splitters, one before the eq and one after the eq. Select source to feed eq and then relevant line out (via the other splitter) to choose correct input on the NAD. Given the turntable needs to go to the phon input (for phono pre-amp) and the DAC needs to go to the Line 1 to avoid going through the phono pre-amp. Can't imagine a couple fo good quality RCA splitters would introduce much distortion or sound degradation...

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Ideally, the equaliser should be between a pre amp and power amp. Using splitters won't work, because in particular the cartridge will be directly connected to the DAC output, which will potentially do it no good but equally will totally mess up it's response. You could use some sort of switch and the same for the output from the equaliser, but this is starting to get rather complex and messy. The easiest way would be a separate phono stage and an equaliser with more than one input. You could pick up a perfectly reasonable pro-ject or similar and then you'd just need one input on the amplifier.

The other suggestion would be to contact NAD and see if there is any way the 368 could have power amp inputs added. That would be a whole heap easier all round, and give you a lot more flexibility. I must say that even if it works, feeding the cartridge output into the equaliser before a phono stage isn't ideal.

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1 minute ago, rabski said:

Ideally, the equaliser should be between a pre amp and power amp. Using splitters won't work, because in particular the cartridge will be directly connected to the DAC output, which will potentially do it no good but equally will totally mess up it's response. You could use some sort of switch and the same for the output from the equaliser, but this is starting to get rather complex and messy. The easiest way would be a separate phono stage and an equaliser with more than one input. You could pick up a perfectly reasonable pro-ject or similar and then you'd just need one input on the amplifier.

The other suggestion would be to contact NAD and see if there is any way the 368 could have power amp inputs added. That would be a whole heap easier all round, and give you a lot more flexibility. I must say that even if it works, feeding the cartridge output into the equaliser before a phono stage isn't ideal.

Noted re. feeding the cartridge direct into eq before a phono stage, thanks for that.

I have a ART DJ Pre I've used in the past, just my hunch is the phono stage in the NAD is superior. So I can work around phono pre-amping the cartridge prior to the eq.

By splitters/selectors I guess I meant switches (rather than a splitter cable alone) i.e. two RCA's one side of switch and one RCA the other side of the switch. Select which feeds the eq and then select which feeds either line in or phono in on the NAD. Kind of messy, but not overly so: two extra cables and two switch boxes by my calculations... using a pre-out to power amp to hook up eq would be two new cables in ideal solution, using switch box would be four new cables and two new splitter boxes.

Pre-amp inputs on the NAD is a great idea, but I suspect would be cost prohibitive.

Seems best solution is an eq with two line ins and two lines outs. Then either use the ART DJ phono stage or buy a better one to go before the eq. My only concern there is the built in phono stage on the NAD is meant to be very good and might be costly to equal.

Thanks Rabski.

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Never simple in this daft hobby!

At least there are plenty of options there. Certainly worth asking NAD. If nothing else, if they say it can be done straighforwardly, there are ceraynly others who could probably do it for less. However, you might end up pleasantly surprised.

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Schiit Loki - amazing little thing and a big upgrade for little outlay

15600128253371198796098.jpg

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Just now, knaithrover said:

Schiit Loki - amazing little thing and a big upgrade for little outlay

15600128253371198796098.jpg

I'm using mine between the source and amp (Nad C320BEE)

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Posted (edited)
23 minutes ago, knaithrover said:

I'm using mine between the source and amp (Nad C320BEE)

That looks really interesting.  Probably not quite enough control, for my rather unorthodox eq'ing though. The Loki appears to have controls as follows: +/- 12 db at 20Hz and 8kHz, +/- 6db at 400Hz and 2kHz.

Playing around with the Behringer (nine sliders) over past couple of days, whereas I started with a V shape, I now tend to broadly set as follows:  +6db at 50Hz. An unusual peak of about +8db at 500Hz. 1kHz to 4kHz flat. +4db at 15kHz. Note: I always where possible eq passively, by reducing frequencies, but the effect is similar.

That strange break of a V shape at around 500Hz would also end up lifting the sound between 1 - 2 kHz on the Loki, in a frequency range where I want to reduce it...

Going to set those points only on the Behringer: 20Hz, 400Hz, 8kHz and 2kHz. Then plot the others accordingly (as they would shape on the Loki) to increase or decrease either side and see if it sounds good to me.

If only it also had a 1kHz setting as well I think it would be perfect!

Thank you.

Edited by Headcoat
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4 hours ago, Headcoat said:

eddie-baby: given I'm really looking at eq'ing the turntable and cd player how would I go about introducing a dsp into the hi-fi chain. Of course, I could set it originally on my computer, but the computer is not part of my listening chain in any form. Additionally, I would assume this would mean the turntable goes through an A/D conversion in the DSP for eq'ing and then back to analogue via a DAC in the DSP, not sure that would be good for the analogue sound?

Just stick it in between the pre power part of your amp as if its just a regular graphic eq, actually thats what they recommend with a lot of DSPs. You dont have to have the PC linked up at all, you just use it initially to set a collection of settings, either ones you stick with or can flick through. Some even come with remote controls so once its set you can use the remote control to flick through patches you've saved.

Its just a black box, but it will have all the functionality and more of a full size eq.

These are few different types from this place if its something that interests you.

https://www.minidsp.com/

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I have a Technics SH 8055 plugged in to my pre tape loop. It gives me an extra tape loop, and a nice pink noise source. I do eq occasionally, cause I am going through a speaker experimental phase, but I always seem to switch it out eventually, as it does have a "finger print". I have a Beringer 8024 eq, it can do auto eq, but I haven't tried that yet.... makes my tape deck sound like a cd player.... If i wanted to use it properly I would go for the 96khz version as a matter of principle. It was a conceptual ripoff of the BSS varicurve 926 (used to work there). That is an analog parametric EQ that could auto EQ with a microphone. That did a good job and sounded nice.

If you can, it is better to plug the eq before the volume control, especially digital eq, or carefully juggle the levels to make sure you are getting the best value from your bits. And gentle wide parametric EQ is preferable to lots of narrows.

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3 hours ago, eddie-baby said:

Just stick it in between the pre power part of your amp as if its just a regular graphic eq, actually thats what they recommend with a lot of DSPs. You dont have to have the PC linked up at all, you just use it initially to set a collection of settings, either ones you stick with or can flick through. Some even come with remote controls so once its set you can use the remote control to flick through patches you've saved.

Its just a black box, but it will have all the functionality and more of a full size eq.

These are few different types from this place if its something that interests you.

https://www.minidsp.com/

Problem is I only have a pre-out on my amp, and no pre-in. I think NAD did this to allow people to bi-amp / monoblock with the relevant add-on NAD power amp. Had a look at the DSP link, think I want to avoid an eq with an onboard ADC and DAC, kind if defeats the purpose of vinyl playback, so an anlogue eq seems the way to go. Appreciate the suggestions however.

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15 minutes ago, dave said:

I have a Technics SH 8055 plugged in to my pre tape loop. It gives me an extra tape loop, and a nice pink noise source. I do eq occasionally, cause I am going through a speaker experimental phase, but I always seem to switch it out eventually, as it does have a "finger print". I have a Beringer 8024 eq, it can do auto eq, but I haven't tried that yet.... makes my tape deck sound like a cd player.... If i wanted to use it properly I would go for the 96khz version as a matter of principle. It was a conceptual ripoff of the BSS varicurve 926 (used to work there). That is an analog parametric EQ that could auto EQ with a microphone. That did a good job and sounded nice.

If you can, it is better to plug the eq before the volume control, especially digital eq, or carefully juggle the levels to make sure you are getting the best value from your bits. And gentle wide parametric EQ is preferable to lots of narrows.

Thanks Dave. Best to put eq before volume control, interesting point which would fit with the way I seem to be heading, any reason behind that recommendation? 

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44 minutes ago, Headcoat said:

any reason behind that recommendation? 

Active eq has some noise. If it is before the volume control you can turn down the noise.

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Super Wammer
Posted (edited)
I found this in the manual for a Behringer GE, quite interesting for those of us using active xovers with the ability to boost/reduce frequencies
 
Effects of frequency on voices
 
40 to 125 Hz
Sense of power in some outstanding bass singers.
 
160 to 250 Hz                     
Voice fundamentals
 
315 to 500 Hz
Important for voice quality.

630 to 1 Khz

Important for voice naturalness. Too much boost In the 315 to 1 kHz range produces a telephone-like quality naturalness.  

1.25k to 4k

Voice fricatives-accentuation of vocals. Important for speech intelligibility. Too much boost between 2 and 4 kHz can mask certain speech sounds e.g. "m", "b", and "v" can become indistinguishable. Too much boost anywhere between 1 and 4 kHz can produce "listening fatigue". Vocals can be highlighted by slightly boosting the vocal at 3 kHz and at the same time slightly dipping the instruments at the same frequency.

 
5k to 8 KHz
Accentuation of voice. The range from 1.25 to 8 kHz governs the clarity of voices.
 
10-16 KHz
Too much boost causes sibilance.
 
Effects of frequencies on music
 
31-63Hz
Fundamentals of bass drum, tuba, double bass and organ. These frequencies give music a sense of power. If over-emphasised they make the music "muddy". The 50 or 60 Hz band is also used to reject AC mains hum.
 
80-125Hz
Fundamentals of lower tympani. Too much boost produces
excessive "boom". 100 or 125 Hz are also used for hum rejection
 
160-250 Hz
Drum and lower bass. Too much boost produces
excessive "boom". Also useful for 3rd harmonic mains hum rejection 
 
315-500 Hz
Fundamentals of strings and percussion
 
630-1KHz
Fundamentals and harmonics of strings, keyboards and percussion. Boosting the 600 to 1 kHz range can make instruments sound horn-like.
 
1.25-4KHz
Drums, guitar, accentuation of vocals, strings and bass. Too much boost in the 1 to 2 kHz range can make Instruments  sound tinny. Too much boost anywhere between 1 to 4 kHz can produce "listening fatigue".
 
5-8KHz
Accentuation of percussion, cymbals and snare drum. Reduction at 5 kHz makes overall sound more distant and transparent. Reduction of tape hiss and system noise. The 1.25 to 8 kHz governs clarity and definition.
 
10-16KHz
Cymbals and overall brightness. Too much boost causes sibilance. Reduction of tape hiss and system noise.
 
 
Thought this would be useful when tweaking 
 
 
Edited by MF 1000

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