building a kit soon....RCA outs and tone controls? or is this sacrilege....

[91rtstealth]

Hello.  I'm going to be building a Crack Kit with the Speedball Upgrade within the next few months.  I want to have the ability to use it as a preamp as well for my stereo system.  I know I can use a quarter inch to RCA adaptor out of the headphone jack, but I would like to add RCA Outputs to the kit as well if it's not too complicated.  What are the pros and cons to this?

And also....as much as I know it's frowned upon, I like having tone controls because I totally loathe sibilance and overly bright recordings and I want to be able to dial the treble back some if a recording is harsh.  I'm also a bass head, so having the ability to boost the bass from time to time would be great.   I just have no idea how to wire something like that up and I'm wondering if anyone else has done it and could share a diagram with me to show how they did it.  Or is it just a bad idea, and if so, why? 

Thanks in advance

[Paul Birkeland]

Hello.  I'm going to be building a Crack Kit with the Speedball Upgrade within the next few months.  I want to have the ability to use it as a preamp as well for my stereo system.  I know I can use a quarter inch to RCA adaptor out of the headphone jack, but I would like to add RCA Outputs to the kit as well if it's not too complicated.  What are the pros and cons to this?

In the stock kit, we use the shorting headphone jack to allow the big output coupling caps to charge quickly if no headphones are plugged in.  If you want to add separate preamp outputs, you'll have to defeat this functionality of the Crack.  This is certainly a big factor in recommending the use of the adapter cable instead.  The Crack-a-two-a avoids this issue with a more complicated circuit and you could easily add preamp outputs to it without this issue.

And also....as much as I know it's frowned upon, I like having tone controls because I totally loathe sibilance and overly bright recordings and I want to be able to dial the treble back some if a recording is harsh.  I'm also a bass head, so having the ability to boost the bass from time to time would be great.   I just have no idea how to wire something like that up and I'm wondering if anyone else has done it and could share a diagram with me to show how they did it.  Or is it just a bad idea, and if so, why? 

For tone controls, usually you want an extra 40dB of gain driving the tone stack so you can go +/-20dB with your adjustments.  The Crack doesn't have 40dB of gain in the first place, and the directly coupled nature of the circuit means that building something like this in would be pretty difficult. 

You can use an external EQ between source and the Crack, that's definitely where I would start.

[Laudanum]

What's your source for the Crack going to be?   I have a headphone system set up with multiples sources.  A turntable and CD player into a Bottlehead preamp feeds the Crack.  Also my laptop into a DAC to the Crack.  I also can feed it from the line out of my DAP  (been doing that a lot lately).   Both the Laptop player software and the DAP have EQ's.  I don't use those EQ's but that's a pretty simple solution if you are using either of those as a source.   

Schiit audio also makes a relatively inexpensive tone control unit called the Loki.  It's a compact 4 band unit.  I think it's about $150.  I don't own one but I've read some positive feedback for it.   Again, not using eq myself,  I really don't know what else is out there but  I'm sure there are plenty of other options. 

 

[Deke609]

  I'm also a bass head

A tangent, but hopefully still responsive to your stated interests. If your love for bass extends into "sub-bass", see if you can get your hands on a pair of JVC SZ-2000 headphones. Paired with a good digital equalizer (I find the freeware Peace and APO Equalizer combo quite good) and a headamp with a bit of oomph, they are mind blowing. With Peace/APO-E configured for +15db gain from 10Hz to 40Hz and otherwise pretty flat and near 0db, and with the preamp gain set to about -10db, the bass is out of this world provided your headamp can supply enough gain.  I use a $300 or so solid state headamp that I picked up from MassDrop (as it used to called) years ago. I swear I get an endorphins rush from any track by Kendrick Lamar or Jay-Z.  At such low frequencies, the bass isn't so much "loud" as it is literally "visceral". Most amazingly, I don't notice any distortion of mids or highs. For example, female vocals over top of a pounding sub bass beat or groove sound just as clear with the +15db sub-bass boost as without. I'm sure it would be same with drum and bass or bass heavy electronica, etc.

just fyi, in case this might interest you.

cheers, Derek

[91rtstealth]

This is all very useful information.   Thanks.  I'll just use an adaptor to keep things simple and use an EQ if necessary.   

As far as my source goes, it will usually be a Chord Mojo coming out of my laptop or iPad, so I can use a software EQ if necessary.   

Thank for the basshead tip on the headphones.  I'll look into it.   

[91rtstealth]

That Schiit Loki looks perfect...I think i'll grab one of those...