BassmanPaul

That's because it is. The output from a 2x10 and that of a 1x15 is about the same. A 1x15 has no hope of keeping up with a 4x10 no matter how hard it tries. The pairing usually has the fifteen failing after a time. Best pairing you can get is with identical cabinets.

https://www.basschat.co.uk/forum/20-amps-and-cabs-for-sale/

Many, many players think that a larger cone equates to a greater ability to produce lows. This is far from the truth as there are 15s that go higher than an average ten and tens, like those used in my Acme cabinets, that will happily thrust a Low B all day long. Secondly matching cabinets always work well together whilst dissimilar may not. Try stacking your boxes on their ends so that the drivers are vertical. You may just love the result. I certainly did! I love your Warwick. My Streamer is still the best sounding bass I own. It's tuned B E A D as I usually now play my six string basses.

What, if anything, did you think that the 15 was going to add to the 2x10? Curiosity feeds the question.

It's a pity that Fender never revisited the original 2x12 Bassman speaker cabinet and incorporated all the knowledge we gained from Thiele and Small. I still think my blonde black face Bassman looked loverly on stage. It just sounded like crap!! The amp section through a Marshall 4x12 worked so much better!

Just listen to the demo video to hear what it sounds like. As for picks, I stopped using them back in the Sixties! LOL

@ValleyArtsSo how you doing with this project?

But, but, but it's a transistor amp with just one lonely 12AX7 twin triode!!!

It's great to hear about companies who stand behind their products.

@msb You've got more stuff than even I have and that's saying something!!

You're from Chester a city I have a soft spot for. At one time my family lived in Helsby in fact they are all still there after they all passed away. I went to Helsby Grammar School for Boys and bought my first bass in 1962 when I was sixteen. Thank you for an unintended walk though memory lane. Stay well.

@ValleyArts did you get the Bright box repaired?

For me it's the Acme B2 2x10 three way cabinet. I use a pair stacked on their ends for a vertical 4x10. Stacked this way improves dispersion out into the room and brings the sound up by my ears for easy monitoring. On stage the set just takes the same amount of room as one cabinet. The plum is how well they handle the low B of my six stringed instruments. A pure delight!

If you feel that you need four tens may I humbly suggest that you consider a pair of 2x10s stacked on their ends for a vertical 4x10. This brings the top cabinet closer to ear level and two cabinets take up the same stage area as one. They also disperse better out into the room. All in all a win win situation.

To explain a bit more: a 5U4, or a GZ34 for that matter, can power a typical 50W amp. The Mesa amp being 100W needs more current from its power supply. Thus two rectifier tubes to supply that. If you try to run the amp on one rectifier you risk blowing the tube which could possibly take out a high voltage secondary winding on the power transformer. It's something that you just don't want!

But not cheap!

I'll bow to your superior knowledge. Many thanks for helping out.

It looks as though the pre-amp is powered between the positive rail via a regulator and ground. that's a little odd in my mind. The negative rail just seems to drive a couple of lamps. Hmmm!

Connector pin assignment Pin 1 - Ground Pin 2 - Full Positive rail Pin 3 - Audio Signal Pin 4 - Full Negative rail Pin 5 - Not used Pin 6 - Not used

Thank you @bartelby for going to the trouble of supplying the schematic. @prowla if you are wishing to use this pre-amp standalone you'll have to provide a power supply and audio cabling to feed a suitable power amp. Good luck with that!

I'd be looking at it from below!

I have to admit that I'm glad that I don't have to lift those amps though the Class D, which is not in anyway 'Digital', is going to be much lighter. That being said, I hope you derive much pleasure from using them.

I agree that it's for connecting a Trace power amp board. I tried to read the schematic I found on the web and could see the wiring for the socket but the site was flaky so the diagram didn't stay long enough on my screen to be certain. I'm betting that this unit came from a deceased head as it has no connectivity on the back panel.

I'd go to Glasgow to try it out but I can't swim!

It's not a lamp it's an electron tube/valve. No it's not safe to use. GZ34/5AR4 tubes are readily available and are simple to install. Pull the broken one out and push in the replacement tube in it's place rotating the tube as needed to let the key into the socket base. it's that simple. Edit: Apparently the two rectifier tubes are 5U4G. I beg your pardon. Same applies though.