Blackstar 250 active cab with own preamp

[markbunney]

Has anyone had any experience of using the Blackstar active cab with their own preamp?

 

I have been looking into getting one of these and plugging my Sansamp into it but can’t find any reviews of this, or anyone doing a similar thing.

 

Blackstar said you can plug a preamp or Helix (which I am also looking to get) and the cab will go up to 250 watts.

 

am getting fed up trying to buy a new head (see my other thread about broken amps) so looking into other options

[BassmanPaul]

I don't think that a SansAmp has enough output to drive the power amp properly. It depends on the input sensitivity of said amp. The SansAmp was designed to work into the normal input of a bass amp therefore instrument level.

[Downunderwonder]

Result also depends on Blackstar. If they did the same as GK did with their active bass expansion cabs you're SOL. Those require the hyperactive output of the matching GK combo extension output. I don't know of anything that will substitute.

 

What's the input sensitivity spec of the cab amp? It will be very obvious from that if you have a chance.

 

30 minutes ago, BassmanPaul said:

I don't think that a SansAmp has enough output to drive the power amp properly. It depends on the input sensitivity of said amp. The SansAmp was designed to work into the normal input of a bass amp therefore instrument level.

 

Later versions have quasi "Line Out" Level switch which has some oomph to it but not proper Line Level.

 

So it's a definite maybe if a Sansamp can kick it. Sensitivity is the key.

[Downunderwonder]

On 16/05/2023 at 03:12, markbunney said:

or anyone doing a similar thing

There's a clue there that you will get your answer quicker from the sensitivity spec.

[markbunney]

Thanks for the replies. I can’t find readily available info on the input sensitivity, but will keep digging 

[Downunderwonder]

1 hour ago, markbunney said:

Thanks for the replies. I can’t find readily available info on the input sensitivity, but will keep digging 

Looks like you might struggle to find one new anyway. Ask a seller what they powered it with.

 

I found an Australian site saying you can use a Darkglass pre. Afaik those run on 9v so unlikely to put out much more than your Sansamp, if it is one with 'line' level option.

 

When the description talks about passive input that is the speaker level input being driven from another amp and cutting out the onboard amp.

[Count Bassy]

What do we mean by line level?  A professional standard is  1V + 4db, which equates to approx 3.5 volts Peak to Peak. Well with the capability of a 9 volt battery.

[Downunderwonder]

51 minutes ago, Count Bassy said:

What do we mean by line level?  A professional standard is  1V + 4db, which equates to approx 3.5 volts Peak to Peak. Well with the capability of a 9 volt battery.

The professional standard I recall is 1.4V on a balanced connection, which would need 2.8V on a single leg unbalanced instrument cable feed to account for the 0v on the other leg.

 

I only know from experience that the BDDI version of line is a fair bit less than what a power amp is expecting ie the full pro level. I cobbled up a grab and go rig out of PA and BDDI to do a last minute gig when my actual rig was locked up elsewhere. The output was only enough to make an a minimal amount of boom. The amp could have easily destroyed the cab if it had been fully driven!

 

The way Blackstar word things you could almost expect it to work with any damn preamp pedal on the 1/4 and need Line on the XLR. But they are entirely coy about all of that so I wouldn't buy one without getting some good info.

[markbunney]

8 hours ago, Downunderwonder said:

Looks like you might struggle to find one new anyway. Ask a seller what they powered it with.

 

I found an Australian site saying you can use a Darkglass pre. Afaik those run on 9v so unlikely to put out much more than your Sansamp, if it is one with 'line' level option.

 

When the description talks about passive input that is the speaker level input being driven from another amp and cutting out the onboard amp.

I spoke to Andertons who said they could order me one in, and it would take a week or so to arrive, and I would then have 14 days to return it if it wasn’t suitable. So I might try that.

 

however the fact that i can’t find anyone else who uses it in the way i was planning makes me think it won’t work and I should stick to a normal amp

[Twincam]

You could add a cheap mic pre that sends out line level. 

 

I'm using an art v3 mic pre into a powered monitor that expects line level. For something so cheap I really like it. Upgraded valve. 

[ped]

I’ve got one! But no preamp pedal to try it with.. could I try my VB99?

[markbunney]

1 hour ago, ped said:

I’ve got one! But no preamp pedal to try it with.. could I try my VB99?

If you were able to give it a try and let me know that would be great.

 

the Blackstar blurb, and also Andertons said it would work with most external preamps and modellers

 

thanks in advance

Mark

[ped]

Ok mate I’ll give it a go 👍🏼

[Downunderwonder]

3 hours ago, ped said:

I’ve got one! But no preamp pedal to try it with.. could I try my VB99?

I didn't know what a vb99 was so I looked it up. That thing looks like it could land SpaceX while practicing modes. I didn't look up the spec but if it can't function as a preamp you bought a pup.

[ped]

7 hours ago, Downunderwonder said:

I didn't know what a vb99 was so I looked it up. That thing looks like it could land SpaceX while practicing modes. I didn't look up the spec but if it can't function as a preamp you bought a pup.

I’ve had it for years and it’s my fave piece of kit - I use it as a hub for everything I do although I use it with the normal 1/4” input most of the time these days. It’s a brilliant preamp with the best compressor I’ve ever tried, and thinking about it I’ve used it to drive a power amp before using the main output which I guess would be the equivalent of the output of a sansamp or similar but not 100% sure as it’s mains powered and maybe not a fair comparison?