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This might sound silly but do you have it set to the wrong input or something muted.
I know in the software you can select analog/digital input, and some of the plug ins have output level and mute. Just throwing things out there because your problem seems pretty odd.

From everything I've read most people should have the opposite problem and have to be careful not to clip the input. With the kind of voltage you are throwing at it, I could see it overcoming some sort of mute condition.
 

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I did some re-wiring this past sunday and finally got around to adding the DSP today. I have a USB charger and an 8 foot USB cable powering the DSP. My HU has output of 5v (Pioneer FH-8000BT). I had to raise the gains on my Alpine PDX.4-100 since it outputs at 2v. The sound was acceptable for a first time. I also got some ground noise. How did you ground the DSP? More tuning will be needed to get this thing right.
 

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This might sound silly but do you have it set to the wrong input or something muted.
I know in the software you can select analog/digital input, and some of the plug ins have output level and mute. Just throwing things out there because your problem seems pretty odd.

From everything I've read most people should have the opposite problem and have to be careful not to clip the input. With the kind of voltage you are throwing at it, I could see it overcoming some sort of mute condition.
I know what you a saying, but after reading OP's review again, he had his head unit and his bit-one on full tilt!! Somethings not right with there input specs. This is giving me a bad feeling. Maybe I should have ordered just one first as a test.:(
BTW OP did say you may need a line driver.
 

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The car is still in pieces but it seems to be working now.

It is unfortunate that I'm having to input signal the way I am, it's by far not my first choice.
I think I'll kick off an email to the guys at MiniDSP and see it changing to the Rev A board will remedy the problem and if they'll do anything to help me out with that.

I just took a look at MiniDSP's website again, can't believe I didn't see this:
Important Note: This board is a RevB version with 2Vrms input capabilities. It is the perfect fit for CD player, or any other source which you don't have volume control over. If you intend to feed a lower signal (e.g. Ipod/PC source.. <or maybe line level RCA??>) and would like greater sensitivity, please have a look at our RevA board instead

Looks like the Rev B boards are meant for fixed output sources. This affirms my suspicion that the Rev A board will be more appropriate for car audio use.

I had a little engine whine when i was using the PC to power the board, once I plugged the USB into my 12V outlet adapter it went away. I have a TINY amount of static that is audible through the tweeters but it's almost not worth mentioning.
 

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Maybe I picked up some noise from the re-wiring I did. I had it plugged into the laptop and still had some noise. I'm going to put my passive crossovers back in and test for noise. Once I clean it up I'll put the DSP back in.
 

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The car is still in pieces but it seems to be working now.

It is unfortunate that I'm having to input signal the way I am, it's by far not my first choice.
I think I'll kick off an email to the guys at MiniDSP and see it changing to the Rev A board will remedy the problem and if they'll do anything to help me out with that.

I just took a look at MiniDSP's website again, can't believe I didn't see this:
Important Note: This board is a RevB version with 2Vrms input capabilities. It is the perfect fit for CD player, or any other source which you don't have volume control over. If you intend to feed a lower signal (e.g. Ipod/PC source..) and would like greater sensitivity, please have a look at our RevA board instead

Looks like the Rev B boards are meant for fixed output sources. This affirms my suspicion that the Rev A board will be more appropriate for car audio use.

I had a little engine whine when i was using the PC to power the board, once I plugged the USB into my 12V outlet adapter it went away. I have a TINY amount of static that is audible through the tweeters but it's almost not worth mentioning.
* Version A is meant for consumer line level signal (-10dBV) such as a PC source, Portable media players or any other sources with an output level < 0.9Vrms. The intend of this version is to have high input sensitivity for such low driving sources, hence driving the miniDSP close to the input level ADC like to be (-15dB below headroom).

* Version B is meant for CD player line level (2Vrms), preamplifiers or any other source with higher output driving capabilities. If you intend to insert your miniDSP kit in line with such source, you better use this version otherwise overdriving of the input converters will result in saturation, aka poor sound quality.
If you read this it looks like version b would be better. Notice version b say preamp. In our case that will be our head unit.
 

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Discussion Starter #87
the purpose of the 2v input board is for aftermarket guys who have high voltage pre-outs to protect the inputs from being fried or overdriven in general. I explained a lot of this in detail.

IMO, swapping it out to a rev A board will have no difference. The output voltage of the miniDSP is still going to be the same: 0.9Vrms. This is specifically why I mentioned the use of a line driver if your amp can't produce enough output for your tastes.

A few other guys are running this and haven't complained about these issues. Or, maybe it's just because they understood them more fully going into and thus were prepared for the cons.

Hope you get it resolved,
Erin
 

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If you read this it looks like version b would be better. Notice version b say preamp. In our case that will be our head unit.
They are saying conflicting things. Who knows
 

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Still doesn't make sense to me why my deck (preamp) on full tilt can't drive the input of the MiniDSP, regardless of what I'm getting out of it.

I can understand if i was getting full input level at the DSP and had to turn up my gains a little to compensate for a lower output voltage from the DSP.

But with my deck balls out, the MiniDSP input level never went above -50.

That has me perplexed.
 

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Still doesn't make sense to me why my deck (preamp) on full tilt can't drive the input of the MiniDSP, regardless of what I'm getting out of it.

I can understand if i was getting full input level at the DSP and had to turn up my gains a little to compensate for a lower output voltage from the DSP.

But with my deck balls out, the MiniDSP input level never went above -50.

That has me perplexed.
You wouldn't happen to have the outputs on your 9887 attenuated would you? If you were running in 3 way mode there is a level adjustment for each channel in the crossover, maybe you turned it down?

Do you have another source you could try?
 

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As Erin stated earlier minidsp has excellent customer service, I've emailed Tony a few times and he has always been helpful and informative. I would recommend that you email them with the issues you are having and even if it doesn't fix all your problems right now it may get consideration going forward on new products and development.

The same goes for everyone with small hardware or software problems or suggestions, minidsp is a small company right now, and customer requests could make their way into new products, both hardware and software.
 

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ok ive read through the whole thread and the website including their downloads, and im still not 100% clear about this. have a few questions that hopefully someone can answer :)

1. so which kit should i get for ICE? revA or revB?
2. if i have a three way speaker set and want to go full active on them how many kits should i get? i can still hook up my sub from the head unit to my mono amp right? bypassing the minidsp kit?
3. how can you power the minidsp without using the usb power slot? is there any other way we can just "hot wire" this processor?

thanks guys.

chris b
 

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The issues I'm having are nothing new to me. I've dealt with noise issues and low output voltage. I just need to playing around with this fun little toy to get it working right. I think I still have an old audiocontrol matrix around here somewhere. If not then I can get a couple of Phoenix Gold line drivers.
 

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They have an array of boards to choose from. The most basic is an all analog DSP board, called the miniDSP (which this review is based on).
MiniDSP - miniDSP Kits
Note there are two versions of this board:
Rev A = 0.9V input
Rev B = 2.0V Input
For car application, you’ll want the Rev B version if you have a headunit with a high pre-out voltage. Otherwise you’ll clip the inputs. This may seem like a huge concern when looking at the numbers, but read the “Concerns” section of this review to see my findings on the matter.
hi erin,

re-read all your post and the minidsp website. in fact i also emailed their support team. and you're right i think all my questions were answered by your first post. but anyway, i still have a couple questions:

1. regarding which board to get. it says in their website:

This board is a RevA version with 0.9Vrms input capabilities. It is the perfect fit for PC sources, portable players or any source capable of lowering the signal to this level. If you intend to connect it to a CD player, or any other source which you don't have volume control over, you should purchase the RevB version instead.

since we're hooking this up to our head units with volume control, it kinda conflicts with your post that says for car audio applications we should use revB. im not trying to argue with you. just want to clarify buddy.

when i emailed minidsp here's their reply (btw you're right they do answer promtly :) )

Which kit should i get for car application? revA or revB?
*Answer*: It really depends on your signal. RevA is 0.9Vrms maximum or 2.54Vpp. Most head units show Maximum Vpp so do some research to figure out what device you will be connecting it to.

so with their reply, i guess you're correct in choosing revB because it has a higher Vrms rating right? im just conflicted with what is posted on their website regarding boards vs. volume control sources.

2. regarding plugins. i wanted to have both parametric and the graphic 31 band eq but this is their answer:

You can't have 31band EQ AND parametric. It's all very clearly detailed under the plug-in diagrams(MiniDSP - MiniDSP Pluggins)

i was just wondering if you were able to have both? if we really cant have both i guess the best route is to go with the 31 band graphic eq right?

lastly this is for all those who want a 4 way full active set-up, this is what minidsp recommends:

parts:
2pcs. miniDSP for 4 way: 1 x Left, 1 x Right
1pc. 4way Graphic EQ plug-in if you want graphic EQ OR 1 x 4way PEQ if you want PEQ.

here's another interesting discussion between minidsp and i regarding connecting the sub:

Question: i can still hook up my sub from the head unit to my mono amp right? bypassing the minidsp kit?

Answer: Yes, that's not a problem, you just need to remember is that you'll have to time align your system. So bear in mind that you want to get your sub in line with your miniDSP + internal processing delay.

anyway just really want to make sure before purchasing this product. sounds very promising! thank you erin for discovering this for us.

chris b
 

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I’ll do my best…

1) You want revB if you have a high preout voltage headunit as stated previously. I think you’ve already got this part figured out…
2) You may want to seek further clarification from them. I understand the product only allows one plug-in at a time. I was under the impression (due to lack of correction from anyone there) that you can use more than one plug-in, but after I’ve had time to digest it more myself, I can see how this is not plausible. It may be that you’re only allowed one plug-in per board. If this is the case, then I hope no one bought this unit based simply on the idea that you can have both at the same time. I think they covered this on their website, which is why I REALLY strongly encouraged people to check the website for further info. Like any review, I can’t guarantee that X will/will not work since I’ve only had a chance to use one board.
3) The sub/delay thing is a given. Their answer is what someone here has already mentioned, I believe.

Hope that helps.
 

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thanks erin for your quick response.

yeah i believe that the revb board is the way to go for our/my application since im using alpine 9887 which has a 4v preout.

on the issue on the plug in, id probably go with the 31 band graphic eq because it has more tuning options for me.

one last question that just popped into my mind just now. if we use this processor, or any processor like bit-one...our head unit's eq and time alignment functions wont be of any use anymore right? coz all the tuning will be recognized from the processor. sorry im such a noob when it comes to processors. this is the first time im delving into one.

chris b
 

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If for whatever reason you really needed Graphic and Parametric you could probably run two boards in series, one running the Graphic and one the parametric plugins. You should be able to feed the second board with I2S signals instead of having an extra D/A and A/D conversion (make sure the proper master/slave clock settings are used). You would only use the crossovers on the 2nd board.

This doubles the cost, but there is still no processor on the planet at this price point that would give you this kind of flexibility with both EQ types.

(Contact minidsp and see what they say about that configuration, and ask if they've ever tried it)
 

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If for whatever reason you really needed Graphic and Parametric you could probably run two boards in series, one running the Graphic and one the parametric plugins. You should be able to feed the second board with I2S signals instead of having an extra D/A and A/D conversion (make sure the proper master/slave clock settings are used). You would only use the crossovers on the 2nd board.

This doubles the cost, but there is still no processor on the planet at this price point that would give you this kind of flexibility with both EQ types.

(Contact minidsp and see what they say about that configuration, and ask if they've ever tried it)
i still dont think it would work with my intended set-up (4 way full active) coz the two boards would configure like this:

1 for the left channel
1 for the right channel

so if thats the case 1 board would have the graphic eq plug in, and the other board would have the parametric plug in.

correct me if im wrong though coz im not that technical.

chris b
 
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