I ask this question out of idol curiosity.
I have Graham Audio LS5/9 speakers and the BBC used to use them with Quad power amps.
If my curiosity gets the better of me and I purchase a second hand 405 power amp, how do I connect it to my SN3+HiCapDR?
The SN3 manual shows how to connect the HiCapDR and it shows how to connect a power amp, but there is no diagram showing how to have both connected at the same time. I did a search on the forum but found nothing on this query. Thank you.
@RogerGround Google “using Naim SN3 as a preamp only”. It can be complicated. I would not recommend it.
The Hicap stays connected as you have it now. You can use the DIN4 Bi-amp out socket on the SN3 with an appropriately wired DIN to 2xRCA cable. At a push, you could use the sub out RCAs but IIRC, these are ‘slugged’ with 100ohm series resistors to allow longer cables to be used to connect to the sub, but are not low pass filtered.
Edit - Actually thinking about it a bit more, you don’t need the SNAIC4 back to the SN3 if using an external power amp, so just connect the DIN to 2xRCA cable to the 405 to socket 3 on the Hicap. The SNAIC5 stays.
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Hi @Jaybar
Thank you. Now I know the question to ask I have found the information.
In agreement with you Jaybar
I did try it briefly few years ago when I had the SN3 and it upset the musical balance for me if you get my drift. Bass sounded bit weird etc etc
Just stick with the SN3/Hicap combo , made for each other
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Hi @james_n
Thank you.
Having Googled the correct question I have found the answer on this forum.
- Connect to the Bi-amp Din on the SN3.
Or. - Connect to Din 3 on the Hicap.
Or - Connect to the sub-woofer out on the SN3.
Hi @Bevo
It is just an idol curiosity.
I have no room for power amp, it would mean getting a new rack.
So, if I did go down the power amp route it would have to be miles better than the SN3 to make the trouble of a new rack worthwhile.
It’s idle curiosity. Beware of false idols; I listened to a 405 once and it was the dullest amplifier ever.
Possibly also employed live feeds / or 30ips masters .. not so easy to replicate those.
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Probably best to leave it at curiosity, there is quite a long article on the Mark Hennessey website about recreating the BBC version of the 405. Not for the faint of heart.
I remember many many years ago going on a tour of the then HTV studios in Bristol. The hignlight was not the TV, but the sound. The biggest surprise was that the room was full of 405 amps and speakers, all bearing the BBC logo. Apparently loans were not unusual if there was a special event to cover.
Memory is dim as to the source, three pieces were played, 1812, Ella and Louis and the first time I had heard MJQ, Pyramid. If I could have taken the setup home, I would.
This may or may not be useful but on Page 28 should be informative. Replace the NAP200 w/your amp.
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I think that might have been about rebuilding 405’s with the active crossover for the LS5/8; I think the LS5/9 was originally designed for active operation, but they found that a passive crossover was perfectly adequate so that’s what went into production.
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It was a long read, I sort of missed that
I have a biscuit tin 4HF, better than the SP25 and good looks with it
Hi @marcusman
Thank you, very informative.
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Thank you for the correction to my 05:30 bleary eyed typing.
My wife, who is a retired teacher, is normally on hand for spelling and grammar.
Your wife must have been off duty on two consecutive days.
Yes, it was three days away on 18 month old granddaughter caring duties.
I took one for the team and stayed at home with the dog. Dirty work but somebody has to do it.
How you must suffer! Mrs HH has been away for three days too, back this evening. I must get the vacuum out.
Are you still thinking of the Quad?