Hi
On second hand valve stuff (as with any class A stuff second hand) heat and time will have shortened the life of some components.
This can be true. But there are plenty valve amps which have lasted a long time. Just look at the the number of Quads & Leaks (& others) still around. Components do age but this applies with any electronic equipment. Careful design, quality components & layout does reduce this. At work, there are pieces of valve test kit which date from the 60s & have had very little done to them. Valve amps can & do last a long time.
Hi Data,
hmm not suprising trading station went bust...not exactly cheap...
Some of the items they have sold are not as cheap as private but some are good value for a shop. I have bought some stuff off them in the past which was priced well.
I fancy a BP amp one day scidb, how does it do bass, is it a little on the light side compared to a PP?
Yes they do bass. What you must realise that these amps are different to a lot of single ended amps out there. They don't have the faults of a lot of them. Single ended amps can major on the mid range but can be soft, limp, indistinct or light in the extremes. They can be made quite cheaply due to the small number of components in the signal path. But if you go to town, good results can be had.
The Border Patrol design strengths are
1) The use of triodes through out giving excellent linerity
2) No negative feedback. Due to the use of triodes
3) Good circuit design. low noise amp.
3) Quality components.
4) Interstage transforrmers. Gives very good drive for the 300Bs.
5) Quality output transformers. Give a wide frequency response & less distortion.
6) Choke input power supplies. Gives very good regulation & less noise on the power supply.
All these help the sound quality. The 300B have an excellent sounding mid range but can produce the goods on the extremes when carefully designed. I also find a lot of triodes may sound leaner than pentodes & tetrodes. They are more linear.
You will get a bigger bass sound with other valve amp but not always the speed, dynamics, control, detail & resolution.
I like the overall performance of this amp & prefer it to a large number of Push Pull amps I have heard. This includes areas where the push pull is meant to be king. Whether you perfer it to over amps, I don't know.
The downsides are
1) the cost new. £4500. I got mine ex-dem.
2) The price of Western electric 300Bs. You can get a good range of 300Bs which are on par or better than the Western 300Bs.
3) the low power of 9 watts. Not a big problem if you have high sensitive speakers. Can be used with lower sensitive speakers, it all depends how loud you listen.
The main points of the design can be applied to push pull valve amps. Border patrol now do a range. There is a Push pull with all the design features but with another power supply box. (This contains three choke input supplies.) This means the amp has six in total. There is also a Parallel single ended (18 watts ) with two box supplies.
I do hope to compare the push pull v Single ended.
and I suspect otls are a bit on the quirky side too
I have heard a few OTLs in my time. I have mixed opinions of them. They have never appeared to me as being loads better than an amp with a output transformer. But the Graaf ones are interesting looking ones.
I am probably a PP type really
Maybe, maybe not. Go on amps on their ability to perform. If you go to town on any type of amp, you will get good results.
SCIDB
