Recommend me a cheap, small, good passive DI box (without a preamp)

[kodiakblair]

@Sibob

Naw. Too late I bought the silver Behringer for £15 s/h ages back.

@Phil_T

Were you using the - 20Db pad buttons ?

[paulbuzz]

The thing about DI boxes is that it depends on what you're trying to achieve: do you want to preserve the sound of your bass with maximum fidelity, or do you want to mess with it in some way that you hope to find subjectively pleasing?

If you're trying to maintain fidelity, the answer is easy: you want an active DI box, because electronics that do this are cheap and reliable; nothing is really going to do this any better than the £35 Orchid DI box mentioned by various people above.

If you want the sound to be altered in some way, then all bets are off, because who knows what changes you might deem acceptable or desirable?
Any passive DI box, no matter how high quality, with a passive bass plugged directly into it, is going to alter the frequency response quite radically, because their input inpedance is always too low to match the bass's magnetic pickups properly. This doesn't apply with active basses, because the pickups are buffered by the electronics in the bass, so then you might well notice that the more expensive passive DIs have lower distortion and greater fidelity than cheaper ones. But then if high fidelity is what you're after, you should probably just get an active DI anyway. So at this point, it's really all going to be a bit hit-and-miss which passive DI, cheap or expensive, will do things to the sound that you happen to like. In which case you might as well try out some cheap ones (as long as they're sufficiently well-constructed to not fall apart, which most seem to be...) since they're probably just as likely to make the particular sound you want as a more expensive one is...

Edited November 14, 2017 by paulbuzz

[Phil_T]

@kodiakblair

Not extensively - I seem to recall that one of them was pressed in when I first tried it and turning it off seem to make things slightly better, ie, louder,  so I never used them after that. Why do ask, have you found they make a difference to the tone? I'm using a passive bass so didn't expect to have to pad the signal.

Edited November 14, 2017 by Phil_T

[nilebodgers]

5 hours ago, paulbuzz said:

The thing about DI boxes is that it depends on what you're trying to achieve: do you want to preserve the sound of your bass with maximum fidelity, or do you want to mess with it in some way that you hope to find subjectively pleasing?

If you're trying to maintain fidelity, the answer is easy: you want an active DI box, because electronics that do this are cheap and reliable; nothing is really going to do this any better than the £35 Orchid DI box mentioned by various people above.
....

This is true, to get maximum fidelity you need an active DI as that will present a high impedance input. Passive DIs always introduce some loading due to the transformer - typically a 12:1 ratio is used so a 1.5k loading mic preamp looks like a ~200k load to the instrument (the mic preamp easily makes up the loss of level in the transformer).

The snag with inexpensive active DIs like the Orchid one is that they don't have true galvanic isolation so can be prone to hum loops (no transformer so the earth lift switch only has partial effect in these). Truly isolated active DIs (e.g. BSS AR133, KT DN100 or the Radial DIs) are pretty expensive as they have both active circuitry and a transformer to give a true earth lift (and are rugged pro-level products).

The Behringer DI is a cheap lookalike of the AR133 and is often perfectly ok for amateur/semi-pro applications. It falls down for pro use as the cheap transformer isn't properly shielded so can pick up a load of hum/buzz.

[Sibob]

5 hours ago, nilebodgers said:

This is true, to get maximum fidelity you need an active DI as that will present a high impedance input. Passive DIs always introduce some loading due to the transformer - typically a 12:1 ratio is used so a 1.5k loading mic preamp looks like a ~200k load to the instrument (the mic preamp easily makes up the loss of level in the transformer).

The snag with inexpensive active DIs like the Orchid one is that they don't have true galvanic isolation so can be prone to hum loops (no transformer so the earth lift switch only has partial effect in these). Truly isolated active DIs (e.g. BSS AR133, KT DN100 or the Radial DIs) are pretty expensive as they have both active circuitry and a transformer to give a true earth lift (and are rugged pro-level products).

The Behringer DI is a cheap lookalike of the AR133 and is often perfectly ok for amateur/semi-pro applications. It falls down for pro use as the cheap transformer isn't properly shielded so can pick up a load of hum/buzz.

Orchid will also do custom orders and add/remove things you want. For example I had a transformer added to mine for a small cost, mine cost £42 including postage and came the next day after ordering.

Si

[nilebodgers]

22 minutes ago, Sibob said:

Orchid will also do custom orders and add/remove things you want. For example I had a transformer added to mine for a small cost, mine cost £42 including postage and came the next day after ordering.

Si

Interesting - £42 is very cheap for an active DI with a quality transformer. High quality passive-only boxes are more than that.

Edited November 14, 2017 by nilebodgers
typo

[Sibob]

9 minutes ago, nilebodgers said:

Interesting - £42 is very cheap for an active DI with a quality transformer. High quality passive-only boxes are more than that.

Mine has no battery capability actually, just phantom power, simply as my starting point was their Micro DI rather than the Classic.

So mine sits firmly between the Micro & Classic with feature set, input for instrument, output to amp, and the XLR out sits on the back edge.

 

Si

Edited November 14, 2017 by Sibob

[paulbuzz]

Interesting! Another gold star for John at Orchid!
I assume he incorporated one of the transformers that he uses in the isolator box that he sells as a separate item: http://www.orchid-electronics.co.uk/trans.htm

[Sibob]

1 hour ago, paulbuzz said:

Interesting! Another gold star for John at Orchid!
I assume he incorporated one of the transformers that he uses in the isolator box that he sells as a separate item: http://www.orchid-electronics.co.uk/trans.htm

Looking back through my emails, here's what John suggested:

"The only thing that might be worth adding - is an isolating transformer on the unbalanced output to feed your amplifier, to ensure that earth loop hum would never happen."

Which I went for obviously.

Will pick up one of their re-amp boxes too soon I think, £56....yes please.

Si

[Byo]

On 31/10/2017 at 23:03, 0175westwood29 said:

The radial stage bug is very small and sounds decent I use it as a board di for my meatbox

+1 on the Stage Bug from Radial. It is super small and reliable, it has saved me a couple of times as a backup DI.

[kodiakblair]

@Phil_T

I never use the buttons either. There's a marked increase in volume using the silver box Behringer instead of just plugging into the mixer.

Since I mainly play a single coil P-bass with flats I appreciate the kick in volume,

[Chienmortbb]

The Bass DI from Beringhet is a silver bronze colour so yours is the acoustic DI and voiced accordingly. The BDI-21 sounds good in front of my amp.

[Chienmortbb]

I have just ordered the Orchid Classic DI and hope to use it this weekend. I will report back then.

[Sibob]

I used mine last Friday for the first time (yup, probably 6months after I got it).....really good, very impressed!

Si

[rmorris]

On 11/14/2017 at 17:10, Sibob said:

Looking back through my emails, here's what John suggested:

"The only thing that might be worth adding - is an isolating transformer on the unbalanced output to feed your amplifier, to ensure that earth loop hum would never happen."

Which I went for obviously.

Will pick up one of their re-amp boxes too soon I think, £56....yes please.

Si

So it sounds as if your DI out on the XLR is a 'normal' non isolated balanced output while your parallel feed to your amp is transformer (galvanically) isolated.

I've long thought that it would be an advantage to have the 'Link' output on DI boxes isolated (or fed by a 'Ground Cancelling' type output  that can work into an unbalanced output and still reject 'ground loop' noise effectively - but that's a bit of a different and technical tangent,,,)

[rmorris]

On 11/14/2017 at 02:32, paulbuzz said:

The thing about DI boxes is that it depends on what you're trying to achieve: do you want to preserve the sound of your bass with maximum fidelity, or do you want to mess with it in some way that you hope to find subjectively pleasing?

If you're trying to maintain fidelity, the answer is easy: you want an active DI box, because electronics that do this are cheap and reliable; nothing is really going to do this any better than the £35 Orchid DI box mentioned by various people above.

If you want the sound to be altered in some way, then all bets are off, because who knows what changes you might deem acceptable or desirable?
Any passive DI box, no matter how high quality, with a passive bass plugged directly into it, is going to alter the frequency response quite radically, because their input inpedance is always too low to match the bass's magnetic pickups properly. This doesn't apply with active basses, because the pickups are buffered by the electronics in the bass, so then you might well notice that the more expensive passive DIs have lower distortion and greater fidelity than cheaper ones. But then if high fidelity is what you're after, you should probably just get an active DI anyway. So at this point, it's really all going to be a bit hit-and-miss which passive DI, cheap or expensive, will do things to the sound that you happen to like. In which case you might as well try out some cheap ones (as long as they're sufficiently well-constructed to not fall apart, which most seem to be...) since they're probably just as likely to make the particular sound you want as a more expensive one is...

+1 and saves me writing much the same wrt fidelity etc.

If you want really high fidelity in terms of low frequency distortion from a transformer only solution then you will need a big (expensive) transformer.

But you may well be happy (or happier) with some 'euphonic harmonic enhancement' from a technically inferior transformer.

I'll note that the Pickup / Impedance issue likely doesn't apply to the OP's requirements since, I assume, the DI will be driven from the Ampeg Preamp so I'm assuming that has a low and fixed output impedance ???

So you probably don't need the impedance (and associated level) transformation.

Essentially a passive DI is a component in a system and it's 'sound' will depend on the rest of the system.

An active solution can buffer itself from the effect of the input source and output load and better define its operation.

 

 

Edited December 20, 2017 by rmorris
typo

[rmorris]

On 11/14/2017 at 08:04, nilebodgers said:

This is true, to get maximum fidelity you need an active DI as that will present a high impedance input. Passive DIs always introduce some loading due to the transformer - typically a 12:1 ratio is used so a 1.5k loading mic preamp looks like a ~200k load to the instrument (the mic preamp easily makes up the loss of level in the transformer).

The snag with inexpensive active DIs like the Orchid one is that they don't have true galvanic isolation so can be prone to hum loops (no transformer so the earth lift switch only has partial effect in these). Truly isolated active DIs (e.g. BSS AR133, KT DN100 or the Radial DIs) are pretty expensive as they have both active circuitry and a transformer to give a true earth lift (and are rugged pro-level products).

The Behringer DI is a cheap lookalike of the AR133 and is often perfectly ok for amateur/semi-pro applications. It falls down for pro use as the cheap transformer isn't properly shielded so can pick up a load of hum/buzz.

Yes - working out the real transformer operating conditions requires knowledge of the source and load impedances, transformer specs' and a calculator !

The specs are fairly meaningless without a test circuit diagram.

re isolation - Orchid state that they have appropriate (non switchable) circuitry to obviate the need for earth lift and also allows phantom operation.

Without having one in front of me I asssume this is along the lines of a resistor / capacitor parallel connection from the input 0V to chassis ?

This should work in nearly all cases (exceptions I'm thinking are eg outside broadcast in electronically hostile environments).

[Sibob]

58 minutes ago, rmorris said:

So it sounds as if your DI out on the XLR is a 'normal' non isolated balanced output while your parallel feed to your amp is transformer (galvanically) isolated.

I've long thought that it would be an advantage to have the 'Link' output on DI boxes isolated (or fed by a 'Ground Cancelling' type output  that can work into an unbalanced output and still reject 'ground loop' noise effectively - but that's a bit of a different and technical tangent,,,)

That's my understanding of how mine works. 
It was silent through the PA I should mention.

Cheers
Si

[Chienmortbb]

I should add that a decent transformer is a lot more expensive than most Passive DIs