Apologies if this topic in one form or another repeatedly rears it's ugly head....I'm just unsure of the current availability of the various potential solution brands, and their fitment.
I would like to try a different driver than the Fostex 125wKeN I currently use in my FH mk3.
I'm using a 4 watt OTL amp to drive the speakers, so sensitivity/efficiency is a consideration.
It would be ideal if a replacement driver would be "plug and play" and fit the existing driver opening shape and size of the cabinet without the use of a spacer, or requiring extensive modification.
I don't ask for much, do I?
It's time for me to consider an incremental change in my rig. I love my FH's, and thought it might be fun to "hot rod" them a bit.
I would like to try a different driver than the Fostex 125wKeN I currently use in my FH mk3.
I'm using a 4 watt OTL amp to drive the speakers, so sensitivity/efficiency is a consideration.
It would be ideal if a replacement driver would be "plug and play" and fit the existing driver opening shape and size of the cabinet without the use of a spacer, or requiring extensive modification.
I don't ask for much, do I?
It's time for me to consider an incremental change in my rig. I love my FH's, and thought it might be fun to "hot rod" them a bit.
If you have rebated the baffle, the only drop in would be FE126 (or FE127 if you could find them). The FE126 is some 3dB+ more efficient than the FF125 which helos if you are running out of juice. What you pay for the greater sensitivity is less bass capability, that is partially counteracted by less (or none) stuffing in the front below the driver. The FE126 is also the driver that really benefits from corner loading.
If you are willing to change the driver rebate, the Alpair 7x could be retrofitted transparently (ie new rebate is larger and deeper than that for the FF125*), but even the more efficient a paper version is less so than the FF125.
If your OTL is typical -- more power with higher impedance -- then a 16 ohm driver would be beneficial on that front. I know of none.
dave
If you are willing to change the driver rebate, the Alpair 7x could be retrofitted transparently (ie new rebate is larger and deeper than that for the FF125*), but even the more efficient a paper version is less so than the FF125.
If your OTL is typical -- more power with higher impedance -- then a 16 ohm driver would be beneficial on that front. I know of none.
dave
That or cutting a big hole ad adding a supraBaffle (after the fact routing can be an issue). The latter a solution if you try the 1st and it messes up.
dave
The P10 SB kit was designed to be used with a mating front baffle with a large rectangular opening, and attached with machine screws to threaded inserts.
If you don't need to frequently remove / swap drivers of different sizes, enlarging the existing driver cut-out- to, say a 5x7" rectangle, and fabricating a new driver plate to suitably cover that opening should work just fine.
The attached sketch shows how we implement it - our optional SB plates are approx 1 1/2" wider than the enclosure, with beveled edges and small "cheeks" that wrap around the sides, but you could easily them the same width.
It won't be a particularly mess free operation.
As Dave notes, the only driver that'd drop in to rebated Fostex pincushion frame pattern would be the 126 - and as much as I generally prefer the A7 family, with your available power, the Alpair's lower net sensitivity could be an issue. No doubt there are lots of folks running A7s with flea watt amps - Dave has my pair of ACA Class A units on hand, but I've not had opportunity to hear them driving anything in his room - there's no assurance that'd be enough for you.
If you don't need to frequently remove / swap drivers of different sizes, enlarging the existing driver cut-out- to, say a 5x7" rectangle, and fabricating a new driver plate to suitably cover that opening should work just fine.
The attached sketch shows how we implement it - our optional SB plates are approx 1 1/2" wider than the enclosure, with beveled edges and small "cheeks" that wrap around the sides, but you could easily them the same width.
It won't be a particularly mess free operation.
As Dave notes, the only driver that'd drop in to rebated Fostex pincushion frame pattern would be the 126 - and as much as I generally prefer the A7 family, with your available power, the Alpair's lower net sensitivity could be an issue. No doubt there are lots of folks running A7s with flea watt amps - Dave has my pair of ACA Class A units on hand, but I've not had opportunity to hear them driving anything in his room - there's no assurance that'd be enough for you.
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Thanks Chris. All your info helps me make my next move.
Think I'll check in with the designer and ask for an opinion regarding the
load to the amp...must admit the Mini Beast doesn't seem to be working very hard driving the efficient 125wKeN's.
I'll reference the sensitivity specs on the Alpairs.
The file is great and may come in very handy. I stashed a copy.
I seem to tweak my system every couple years. I can feel the next mod getting closer.
Think I'll check in with the designer and ask for an opinion regarding the
load to the amp...must admit the Mini Beast doesn't seem to be working very hard driving the efficient 125wKeN's.
I'll reference the sensitivity specs on the Alpairs.
The file is great and may come in very handy. I stashed a copy.
I seem to tweak my system every couple years. I can feel the next mod getting closer.
While we're on the subject (and sorry to hijack your thread, Rabco) can you, Dave or ChrisB, give a simple breakdown of the advantages/disadvantages of the various Alpair 7x models?
I am on a tight budget and looking at some hefty shipping costs, so I want to make the most of the drivers I get. As an example, the cheapest shipping for 2x 7Ps is USD120 to my place. So, the difference of $20-30 in a driver is less of an issue - if the most expensive is the 'best', then I may as well buy them as the shipping is going to outweigh the cost of the driver in any event.
I am on a tight budget and looking at some hefty shipping costs, so I want to make the most of the drivers I get. As an example, the cheapest shipping for 2x 7Ps is USD120 to my place. So, the difference of $20-30 in a driver is less of an issue - if the most expensive is the 'best', then I may as well buy them as the shipping is going to outweigh the cost of the driver in any event.
I would choose the metal cone driver. My opinion.
The paper is more efficient, but more forward, somewhat more like a Fostex FE driver. They are particularily hard until they have had massive break-in (1000 + hrs).
Some people love them. Having an SE tube amp will be the best match for them.
If you have heard A10.3 vrs A10p or A6.2m vrs A6.2p the difference between metal & paper are similar. The difference between A7.3 and A7p is not at all the same. The A7p better fits the stereotype of a metal cone driver, the metal cone that of a paper driver.
dave
The paper is more efficient, but more forward, somewhat more like a Fostex FE driver. They are particularily hard until they have had massive break-in (1000 + hrs).
Some people love them. Having an SE tube amp will be the best match for them.
If you have heard A10.3 vrs A10p or A6.2m vrs A6.2p the difference between metal & paper are similar. The difference between A7.3 and A7p is not at all the same. The A7p better fits the stereotype of a metal cone driver, the metal cone that of a paper driver.
dave
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